Hi,

I'm completely new to the forum so on this occasion I would like to say hi! HELLO! I have nothing to do with building kit cars unfortunately but because your magnificent forum looks like it has got loads of people knowing they way around bike carburetor setups I think it's the best place to drop in and seek for help.

I'm building my 1986 Honda Civic for street use and I'm halfway through converting it into bike carburetors. My problem is, that it won't rev on full throttle. It cuts out and my wideband shows massive drop in AFR. It will go up in revs when I throttle it gently though, idle is beautiful too and it has no problems with starting etc. - two or three pumps of throttle, turn the key and it fires right up. I'm running a stock fuel pump which is mechanical and a fuel pressure regulator. The reg is fully open at the moment and the gauge shows 0 all the time... The fuel pump is self regulated anyway. I've been told by people from Honda forums that this pump should be more then enough for it. I was suggested that the main jets could be too small... I wanted to verify that before I take the entire thing apart again.

Here's the short video of how it runs, you can see the AFR gauge readings there when I rev it gently and boot it:


http://www.youtube.com/watch?v=m6_7U31MzVk

Thanks a lot in advance!

Regards,

Tom

[Edited on 22/7/13 by spuker1]

dont think afr should be any where near 17 at idle. i thought around 14 was the norm but could be wrong!
nice car btw

have you changed the jets to suit the engine or are they the standard ones for the bike?

The first thing I was asked, when I booked for a Dyno carb setup was " has it got the bike fuel pump fitted?" bike carbs don't like car fuel pumps apparently. I think a Dyno set up is essential, the difference before and after is night and day, and well worth the £96 it cost, plus you get a Dyno readout for bragging rights
Welcome to the forum by the way.

14.7:1 is the gsoline afr. ratio to aim for at idle. 17 is way to lean so dont over rev it in its current state! hight egt will be occuring so go steady!

Hi,

Have you changed the main jets ?, I hope I'm right in saying that most if not all bike carbs need them enlarged when fitted to a car engine roughly twice the size of the original bike engine.

For example my Suzuki GSXR carbs had standard jets around 112, the car would run but couldn't revout due to insufficient fuelling , even with no load it would seem as thought the rev limiter was set to 4000rpm.

I ended up with the jets being 160, most people seem to end up in the 150 - 170 area.

Thanks for quick replies!

I think AFR around 17:1 on idle is sort of ok for this car. I had my wideband installed when I was running stock carb/filters/exhaust and it would idle around 17:1... it would run a bit hot when standing in traffic though.... The jets weren't changed at all and they are exactly factory spec for the bike it came off (Honda CBX 550 F2). I think they are 90mm. My engine is 1.3, what jet size would you recommend then?

Thanks!

If it was me I'd be starting at around 1.3mm and working up If I had to guess I would say 1.4-1.5 would be about right.

mine are 1.6mmin a 2.0 Zetec with ZX6 carbs.

It is quite possible to get bike carbs running really well without an RR session, just by using your wideband and a bit of trial and error.

Stu

The bore of each carb will have bearing on this , it's not easy or advisable for anyone to guess.

But just looking at percentage increase you are probably looking to start at 125 -130, but its safer for your engine if you are a little over.

You don't have to buy jets , you can buy a selection of micro drills and enlarge them gradually your self.

From somewhere like this:



Drill Service ,Horley,Surrey

Thanks!

I was always going to drill them, I just don't want to do it to my only set. I'd much rather get a spare set that's closer to the diameter I need (they cost around 3 quid per jet, no biggy) and drill that if necessary.

Should I get 120mm ones then and take it from there? Or should I get 130-135mm to begin with?

[Edited on 22/7/13 by spuker1]

I saw this video years ago, and I think its brilliant. Ok its for bike carbs on a bike, but it gives info on how to tune them.
For a 1.3 engine, I guess you could find that the jets might not be too far off already?
The video gives info on what and how to adjust for what rev ranges. I'd say try it first, then look at drilling jets out?

https://www.youtube.com/watch?v=y836ZPjvoMI

Try the clip position
I think you need more fuel at idle 17 is to lean
Bigger jets

Thanks, I will most definitely try bigger jets then. On another forum someone suggested this:

"Have you actually confirmed they slides are opening with your finger with the engine running. After watching your vids one to many times i am still thinking your not getting throttle. The small pilot jet controls idle and just off idle, the Big main jet controls full throttle and the needle attached to the bottom of the slide does most of the stuff in between. If that needle is not coming up fast enough you will go lean real quick."

Could that be an issue too? If yes, what would cause the needle not to go up. Diaphragm is in mint condition and seals are just as good.

I think we're actually getting somewhere! It looks like there's a light in the tunnel with your help guys!!! Let's get it sorted!!!

quote:

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Try the clip position

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quote:

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what is the clip position exactly? how can I adjust it?

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Oh, I see. I don't think that mine is an adjustable one, it just goes into the slider and I think it sits on spring in there. Not too sure how to take it apart...

But I suppose that I could take it from there...

Drill out main jets to 1.3 & fit a faucet electric fuel pump for a bike 1.5 to 2.5 psi sounds like you are possible forcing fuel past the float needles is the exhaust smoke black when u rev it.

Best off with a bike fuel pump, they are low pressure ands self pressure regulating.

I use a Facet electric pump but you need a regulator , my carbs don't like much more than 1 psi before they flood.

quote:

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Originally posted by Surrey Dave
Best off with a bike fuel pump, they are low pressure ands self pressure regulating.

I use a Facet electric pump but you need a regulator , my carbs don't like much more than 1 psi before they flood.

---

Ok,

So I've taped the filters up with good old duct tape and left about 0,5cm gap around the wider end of each cone filter clear. It idles 14,5:1-15,5:1 and it revs up all the way through rev range on between 12:1 - 14:1 (I think). It revs super quick and super smooth now and idle is beautiful. All it was is too much airflow, restricting it helped a lot.

BTW. the needles were going up and down as normal. Just too much air that's all.

My mate who was helping me out, when I mentioned getting bigger jets instead of blocking it off, said that the fuelling is completely spot on and it's normal on bikes to put restrictors in to make it right.

I will get the video up at some point tomorrow probably!!!

All I have got left to do is to reinforce throttle/choke cable bracket and get it all looking neater.

Thanks a lot and stay tuned!!!

[Edited on 22/7/13 by spuker1]

thats a far safer AFR. around 14.7;1 a i said earlier. you were way to lean before. (too much air/not enough fuel)

Sounds like you've just proved how weak and under jetted it is.


Whats the point of putting 4 decent sized carbs onto your engine and then completely restricting them?


Rather than saying you have to much air, you should be saying I don't have enough fuel?


Or am I missing the point somewhere?

quote:

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Originally posted by Surrey Dave
Sounds like you've just proved how weak and under jetted it is.


Whats the point of putting 4 decent sized carbs onto your engine and then completely restricting them?


Rather than saying you have to much air, you should be saying I don't have enough fuel?


Or am I missing the point somewhere?

---

And get a good filter, those cone things won't be doing much good ;-)
Unless I've read wrong (its 5am, and ive not had much sleep) you've taped up and sealed the filters to the carbs? But I don't see you've mentioned sealing the carbs to the manifold?
If theres air getting in between the filters and carbs, you've stopped the air and thats impoved it, then yes, you have not enough fuel rather than too much air. Those filters are very restrictive, and won't do much good.

You can't have too much air through the filters, just not enough fuel.

[Edited on 23/7/13 by blakep82]

Yes, I have taped them up and left a gap on each filter so the air can still go through. And yes, there's no such thing as too much air, there's only not enough fuel. However for those jets it was drawing way too much air going super lean very quickly. I'm happy I've got it running like that because I can make it to the meet next week that I reall wanted to go to and also because there seems to be a noticeable improvement in performance already so when I get the restrictors off and get bigger jets in, it will be even faster!

And for the filters I think they are quite good, still loads of airflow and much more filtration then bare trumpets or trumpets with mesh.

Awesome!!!

[Edited on 23/7/13 by spuker1]

quote:

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Originally posted by 40inches

quote:

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Originally posted by Surrey Dave
Best off with a bike fuel pump, they are low pressure ands self pressure regulating.

I use a Facet electric pump but you need a regulator , my carbs don't like much more than 1 psi before they flood.

---

Spot on. Bike pumps are cheap, and work, they emulate the gravity feed from the tank, very low pressure.

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quote:

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Originally posted by spuker1
And for the filters I think they are quite good, still loads of airflow and much more filtration then bare trumpets or trumpets with mesh.

---

I was looking into ITG filters with blank back plates, but they are quite pricey. I mean it would probably set me off more then the entire bike carb conversion, including carbs themselves... I think those filters have got enough flow for my needs, I just need to get suited jets for them now. I'm running on 90 jets at the moment. What would you think would be the size of jets I'm looking for? 120? 150?

Regarding fuel pump, stock mechanical one is more then enough I recon.

[Edited on 23/7/13 by spuker1]

I know the sausage filters arn't cheap and the likes of the pipercross airbox is silly money...
http://www.pipercross.net/competition/products_600_airbox.asp

but you could make a DIY back plate and airbox in the style of the pipercross one and then all you need is one decent cone filter - which you can then position to draw from cold air

quote:

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Originally posted by spuker1
Regarding fuel pump, stock mechanical one is more then enough I recon.

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I could just as well just get standard CBX550 air box and attach some tubing with a filter to it, there's one for £10 on ebay now but I don't think it will fit in there to be honest, the carb is too close to the firewall, don't forget that this Honda is like a shopping trolley with an engine and a bit less understeer

The stock mechanical pump is ok, because it's self regulating and it has return so if it senses that carb bowls are full it just keeps on pumping but returns the excess to the petrol tank. It's pressure is high enough for most applications but for bike carbs it's actually running on fairly low pressure, so low infact that the fuel pressure gauge isn't showing anything. I've got my fuel pressure reg opened all the way at the moment. I could probably run it with out it at all actually. So yea, I don't think that fuel pump would be ever an issue.

As an alternative to taping up the filters I've been suggested using restrictors that you put right in front of slides in the carbs. Not sure if it would work though because after all I'm still not sure if it needs vacuum before slides to lift them or was it just too much air flowing for the carbs. If it's the former it won't work...

double post, sorry.

Regarding that pipercross airbox, that could be good for bike carbs + turbo

[Edited on 23/7/13 by spuker1]

First off, great that your trying all this, but I'd be surprised if you got more than 10% power increase over your stock 60bhp (25 years ago... probably 55 now). Your engine driven fuel pump isn't magic. It doesn't sense anything. It just pumps away, at 4psi. Quite high for the seals in old bike carbs. It will run fine, then start pushing fuel past the floats. Just buy a bike pump for a tenner and fit it.... problem solved.

Don't ruin your engine with silly fixes. Just allow more fuel in by drilling / replacing the jets. Blocking up parts will be a disaster. Just accept that many of us have tuned different bike carbs with lots of different engines so we know what we're talking about. This isn't RedPepperRacing Foums so we've done this properly and it works.

Also on your EV2 engine, have you connected up the vacuum advance to the distributor? Or the vacuum back to the brake servo?

quote:

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It will run fine, then start pushing fuel past the floats. Just buy a bike pump for a tenner and fit it.... problem solved.

---

As the others say fit a bike fuel pump and drill the main jets out go up in stages on zx9r carbs there is a air correction hole that some people have had to block o stop the carbs going week at high revs

If you do drill the main jets hold the rill bit in a vice and twist the jet by hand don't use a machine

If i was you i would ring Bogg Brothers and they will give you the best advice on bike carbs there very helpful
Jacko
http://www.boggbros.co.uk/index.html

[Edited on 23/7/13 by jacko]

where abouts in the country are you ?

quote:

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First off, great that your trying all this, but I'd be surprised if you got more than 10% power increase over your stock 60bhp (25 years ago... probably 55 now).

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quote:

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our engine driven fuel pump isn't magic. It doesn't sense anything. It just pumps away, at 4psi.

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quote:

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Just buy a bike pump for a tenner and fit it.... problem solved.

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quote:

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don't ruin your engine with silly fixes. Just allow more fuel in by drilling / replacing the jets. Blocking up parts will be a disaster.

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quote:

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Just accept that many of us have tuned different bike carbs with lots of different engines so we know what we're talking about. This isn't RedPepperRacing Foums so we've done this properly and it works.

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quote:

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Also on your EV2 engine, have you connected up the vacuum advance to the distributor? Or the vacuum back to the brake servo?

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quote:

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As the others say fit a bike fuel pump and drill the main jets out go up in stages on zx9r carbs there is a air correction hole that some people have had to block o stop the carbs going week at high revs

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quote:

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If you do drill the main jets hold the rill bit in a vice and twist the jet by hand don't use a machine.

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quote:

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where abouts in the country are you ?

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Obviously I've hit a nerve, I'm not here to get you wound up, sorry if I've come across like a knob. Its just with a dozen experienced people telling you to use a lower pressure pump and to fix the AFR you need to drill the jets, you've opted to stick tape on the filters and leave the pump in. I'm sure you trust your friend and I'm not going to speculate on his experience with engines, so I'll just not get involved. Best of luck with the car and regardless of how you get there, I hope it runs ok.

quote:

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Obviously I've hit a nerve, I'm not here to get you wound up, sorry if I've come across like a knob. Its just with a dozen experienced people telling you to use a lower pressure pump and to fix the AFR you need to drill the jets, you've opted to stick tape on the filters and leave the pump in. I'm sure you trust your friend and I'm not going to speculate on his experience with engines, so I'll just not get involved. Best of luck with the car and regardless of how you get there, I hope it runs ok.

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quote:

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loads of carb fuelled bikes, that they came with restrictor plates (plates with holes in them to restrict airflow) and when taken away all of them would run just like my car did

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I'm sure like all of us you want to get the best out of your car so if the problem is it is getting too much air and not enough fuel you can either restrict the air and limit the breathing and hence power of the engine or increase the fuelling and maximise the power.

I know which I would aim for!

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quote:

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Originally posted by spuker1
I'm option to keep my stock fuel pump because I don't know how to convert it to bike one. I have no idea how would I have to blank the hole after stock pump off and definitely don't want to leave it in turning over completely dry...

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Thanks for that. I think it's definitely a way forward.

quote:

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if you think blanking off the fuel pump is a bodge

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also if your really worried that the engine won't take the full power that your carb's can give them you'd be better off fitting even smaller carb's (my googling suggests your's have 30mm chokes ? )

the logic being its best to have everything working near 100% of its capacity with nice smooth air flow, rather than something working at 70% of its capacity and strangled with a restrictor that messes up the air flow

if nothing else fitting restrictors would be a bit like driving at max. of say 70% of wide open throttle - the efficency of the carb's like this will be much, much worse than say just fitting a set of carb's with 25mm chokes and getting a fully open throttle

or to say it a different way, pick carbs the right size for the power you want to achive - then make everything match that
so your manifold, ports, valves, cams, exhaust pipes and even max. rpm etc. should all match as closely as possible to make the most efficent engine you can - well thats the theory at least




you may find this site useful for background info on your carb's:
http://www.gadgetjq.com/keihin_carb.htm

https://www.youtube.com/watch?v=pw9h1zD_XPA

Ok, this is how it runs now. It actually ran much better last night or I was so excited about it not cutting out as much anymore I thought it's perfect. Obviously it drops AFR in midrange, so definitely need to lift the needles a bit and definitely bigger jets!

[Edited on 23/7/13 by spuker1]

Right then! I've ordered 120 jets and they are still too small, I might go straight up to 150-160 ones to be fair. I've come across first major problem though. Needles aren't adjustable in those carbs and there's no way I could put spacers under them because of the design of the thingy that holds them in place... How much can I adjust the way they will work just with size of main jet and adjusting the air screw? Does it mean that even if I tune it well with needles like that I will get nice idle and low range, no midrange and decend high range power?

I could always shave the needles a bit but because there obviously won't be any going back I will get the jets right first I think... How does the size of the needle affect the changes that bore of main jets made? I mean, If I get main jet's size right and full throttle AFRs will be spot on, will it change much when I get needles shorter/thinner?

I've sort of realised yesterday that I might have to get different set of carbs because of that... It got me a bit depressed to be fair.

Please help me out with that one...

Cheers,

Tom

I Think Dynojet kits include adjustable needles, but not 100% sure. However they aren't cheap.

Stu

Thanks, that would be good but there's no replacement kit for the carbs I've got. I was looking for alternative needles from other Keihin carbs but all of those with splines in them are much longer then mine. Mine from the tip to it's mounting head thing is about 40mm long, the other ones are 60mm+...

Other suggestions?

if there are no kits avalible I belive you can get custom needles made - but the cost will give you a shock

its sounding like you'd be better off with a set of carb's from a more upto date bike (or at least one you can get adjustable needles for) there might even be set thats better suited 'off the shelf'

I was considering that... There's a reason for most of the people using R1 carbs for those conversions right? Anyway, I will try to fit bigger jets (ordered 150s today) and see how far this will take me. If car will be still undriveable I will consider getting different set of carbs. Probably won't loose much money on it as I've bought them dirt cheap and gave them a good clean and rebuild

What set of carbs would you guys recommend for 1.3 SOHC engine? ports are around 35-38mm the stock output is around 70bhp. I'm also on a tight budget so the cheaper the better!

Thanks,

Tom

R6, ZX6R, ZX9R, GSXR....etc are all just as popular as a R1 carb's - but I suspect they are all too big for your little engine


I think you should be looking for a 4cyl bike with say ~80-90 bhp from the late 80's onwards
so at a guess that maybe a CB750 (75bhp, 34mm Keihin's) or GS650 or maybe even one of the GSX's
never used any of those carb's for anything so not sure how good they would be - so you'll need to to your research on any carb to see how tunnable it is before you buy.

[Edited on 31/7/2013 by mcerd1]

Thanks a lot mate, yea I suppose. I've bought these ones as they popped up on ebay in my area for very cheap, so decided to give it a go. I will give it one more chance with massive jets and air screws all the way to the rich side and see how it goes... If there's no luck still I'll sell those on and find something else...

You could consider gsxr600 carbs, or if you want smaller then gsf600.

Personally I hate bike carbs (they just leak and cause fires), so I'd go with gsxr600 throttle bodies and megasquirt it but that will cost you a few quid.

I could go for throttle bodies but my car was running a carb to begin with, so I think it was just much easier to put different carbs on it rather then converting it into injection with throttle bodies. But I might as well do that if I go for my hydra swap (1.6 DOHC head on 1.3/1.5 block)...

As in for leaking, I was expecting that but didn't have a problem with it so far. Not even a dribble.

So are all of those carbs fitted with adjustable needles etc? How about jet availability?

BTW. I'll actually post photos of my car I think





[Edited on 31/7/13 by spuker1]

Bike carbs don't leak and set on fire - they are really reliable, dead simple and if it wasn't for emissions regulations would probably still be widely used on new bikes.

You just need to set them up right.

Stu

quote:

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Originally posted by matt_gsxr
Personally I hate bike carbs (they just leak and cause fires)

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quote:

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Originally posted by spuker1
So are all of those carbs fitted with adjustable needles etc? How about jet availability?

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Thanks guys!

I know about bogg bros but I really really really want to get it done on my own. I haven't got a problem with assessing if runs rich or lean in which parts of throttle/revs because I've invested in the wideband sensor and AFR gauge....

Anyway,

Here's the latest from the bike carb 1.3 saga!

150 jets were still too small. It would still lean out on full throttle and heavier part throttle... I've decided to drill out one of my sets of jets but I've only had 1,5mm 2mm and 2,5mm drill bits so I went for 2mm which in jet sizes is right up 200... I've also adjusted the air screw. Had to have it almost set to all the way out, so had to wrap it in PTFE tape to stop it coming undone beacuse of vibrations. The idle and part throttle is now fine if not a bit on the rich side, but on full throttle it will go like a stabbed rat for about 1,5 seconds and then AFR drops to below 10:1 and bogs....

Here we go again....

I recon the correct size is about 175-180 for my engine if I manage to rise needles... If not then probably 185-190 and will have boggy and crappy full throttle acceleration or a bit lean part throttle...

however,

those 1,5 seconds of right AFR before it floods itself are true 1,5 seconds of geniuine magic. The sound is biblical and I would never think that 1.3 N/A can accelerate like that!!!

So yea, bike carbs - ANNOYING.... but I think it's going to be worth it

Have you given the carb jets a good clean. I blew all mine through with an airline and thought that would be enough - it wasn't. I removed all the jets, idle screws etc, sprayed a load of carb cleaner into a glass and left overnight. Also doused the carbs in carb cleaner at the same time and directed it up through all the holes. The next day I found the jets sat in the glass with loads of black crud in there. Refitted and the difference was amazing - idle screw had to go ino 2 turns further than before to get the same AFR!

Hello! I'm owner of ford sierra 1986 3 door, 2,0 pinto. I bought this car from son of old guy whose died... Engine was dirty but in perfect condition. I have troubles with old weber 2V-ISC carburetor. Only one choke is working properly. So I decide to put in bike carbs from kawasaki ZX9. I wrote this on my local ford sierra forum and all of the people think that in CAN'T WORK, to short manifold, to wide chokes, dizzy troubles, sync troubles, adjusting troubles, bla bla bla etc. I read a lot of UK forums about pinto and here it works in poland NOT I don't understand So i would like to ask You some questions about it because polish sierra forum sucks.

This is my car with 13x7 mangels rims (tires are too high now )




[Edited on 5/8/13 by sharpshooter]

quote:

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Have you given the carb jets a good clean. I blew all mine through with an airline and thought that would be enough - it wasn't. I removed all the jets, idle screws etc, sprayed a load of carb cleaner into a glass and left overnight. Also doused the carbs in carb cleaner at the same time and directed it up through all the holes. The next day I found the jets sat in the glass with loads of black crud in there. Refitted and the difference was amazing - idle screw had to go ino 2 turns further than before to get the same AFR!

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quote:

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Hello! I'm owner of ford sierra 1986 3 door, 2,0 pinto. I bought this car from son of old guy whose died... Engine was dirty but in perfect condition. I have troubles with old weber 2V-ISC carburetor. Only one choke is working properly. So I decide to put in bike carbs from kawasaki ZX9. I wrote this on my local ford sierra forum and all of the people think that in CAN'T WORK, to short manifold, to wide chokes, dizzy troubles, sync troubles, adjusting troubles, bla bla bla etc. I read a lot of UK forums about pinto and here it works in poland NOT I don't understand So i would like to ask You some questions about it because polish sierra forum sucks.

This is my car with 13x7 mangels rims (tires are too high now )

---

Hello, carbs are from 900cm3 kawasaki zx9 year 2000. I have pierburg low pressure fuel pump, with overflow to the tank. At the moment I am waiting for delivery. Carbs cost me 130 PLN this is something about 26 pounds. Salesman said that there are in good condition. Now I need flange, I must buy or make it by drilling. I have welder, 110 amps. I will use a curved tubes 45 degrees, to have proper angle of carbs. I have a lot of place in engine bay, so I can make quite long manifold or short. I don't know which is better for road use. My ECU is Ford ESC-II with MAP sensor and Hall sensor in dizzy. Also i have vacuum brake pump.

Pozdrownienia z tego upadlego kraju nad wisla ;D greetings from poland!

[Edited on 6/8/13 by sharpshooter]

[Edited on 6/8/13 by sharpshooter]

quote:

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Originally posted by spuker1

quote:

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Hello! I'm owner of ford sierra 1986 3 door, 2,0 pinto. I bought this car from son of old guy whose died... Engine was dirty but in perfect condition. I have troubles with old weber 2V-ISC carburetor. Only one choke is working properly. So I decide to put in bike carbs from kawasaki ZX9. I wrote this on my local ford sierra forum and all of the people think that in CAN'T WORK, to short manifold, to wide chokes, dizzy troubles, sync troubles, adjusting troubles, bla bla bla etc. I read a lot of UK forums about pinto and here it works in poland NOT I don't understand So i would like to ask You some questions about it because polish sierra forum sucks.

---

I can't think why it shouldn't work. You might need to do something about fuelling and ignition but other then that it's not a rocket science to make it run... It's harder to make it run properly though... Is your distributor running off the camshaft? is your fuel pump is a membrane one and is running also off the camshaft? what things on your engine need vacuum? I mean it might be as easy as it was in my case when I just chopped the stock manifold up and attached carbs with silicon hose and jubilee clips... Also you might need to fabricate a bracket for throttle and choke cables. Then there is jetting to deal with... what engine size was the motorbike you've got your carburettors from?

---

Thanks for the answer! It sounds very optimistic! See my post above. Cheers

i'm sure a vacuum line for your brakes can be done easily
but the distributor won't like the 'pulses' of air you get from one cylinder of the engine

IMHO the best option is something like the megajolt setup - lots of info here: http://www.autosportlabs.net/Megajolt_Lite_Jr.
other 'spark only' ECU's are available, megajolt is one of the most popular

a programmable setup like megajolt will give you a little more power, better throttle response and better fuel economy than any distributor


for megajolt you'd need:

1 - megajolt ECU - the TPS version (throttle position sensor) - your bike carb's have a TPS built in already
often best to buy this direct form the US: http://www.autosportlabs.com/megajolte-p-41.html

2 - 36-1 trigger wheel to mount on the crank pulley
you can get them on ebay or www.trigger-wheels.com among other places

3 - ford EDIS4 unit - these are found in lots 90's fords - inc. escorts, fiesta's and automatic mondeo's - don't forget the plug with a good length of wire - you can't get these new.

4 - ford VR sensor (crank sensor to work with the trigger wheel) these are found in even more 90's fords, you'll need the plug and a good length of the shielded wire that's attached to it

5 - ford 4cyl coil pack - the early style ones out of the 90's fords will work best - get one with the plug and wires

6 - coil / HT leads - your best to get ones for a 1.3 or 1.6 ford fiesta from about 1993 - these have the old style plug ends and the newer style coil ends

all the donor bits together (items 3, 4, 5 and 6) cost me £25 from my local scrapyard



then the distributor can them be cut down like this (keeping the bearings) to become just an oil pump drive:


some people even mount the new coil pack on top of it...

[Edited on 6/8/2013 by mcerd1]

Megajolt is quite expensive. Something about two times more than my car ;D I'm thinking about "piggy back" ECUmaster DET2 or DET3 http://www.ecumaster.com/en/products/digital-ecu-tuner-3

This is my ECU

quote:

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Originally posted by sharpshooter
Megajolt is quite expensive.about two times more than my car

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oh and I forgot one other thing out need - you need 'Fluro Lined' hose to join the carb's to the manifold

other types of hose will get eaten by the petrol

fastdan sells short lenghts on his ebay shop here: http://stores.ebay.co.uk/DANST-Engineering

Thanks for the interesting ideas! I think that vacuum hose to map sensor should have venturi, thin like a needle. Then pressure should be smooth. This solution is used in some lines from the turbo to sensitive gauge, when read jumps. So maybe with vacuum is the same. About hoses, in every big agriculture shop is branch of "FAGUMIT" this is manufacturer of milion types of hoses. Prices are very low. This is a brochure http://www.fagumit.com.pl/ofertaonline/24.pdf This is manufacturer website http://www.fagumit.com.pl/a-en/#/online

quote:

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Originally posted by sharpshooter
I think that vacuum hose to map sensor should have venturi, thin like a needle. Then pressure should be smooth.

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So I will try with chamber

First days after purchase:
ECU on right


Here is something about http://www.fordsierranet.com.ar/Fotos/Engine%20electrical%20systems.PDF

I need those things x4



Pipes for manifold, various angles 14 PLN this is ~ 2,8 pound each



[Edited on 6/8/13 by sharpshooter]

The simplest way is, however, adjustable dizzy with vacuum steering

quote:

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Originally posted by sharpshooter
The simplest way is, however, adjustable dizzy with vacuum steering

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Hi it's me again and I came across another problem! Please, could you help me again if you can?

Everything is going well but got to a point where I've run out of knowledge or judgement. I went back to 150 jets and drove about and it's perfect/a bit rich with the choke on (except I have to push the choke back in when on idle because otherwise it stalls) with the choke off, idle is spot on and rest of revs is rather lean... also with or without a choke it has a dip in AFR around 3000-3500rpm when it leans out for split second and goes back to normal.

I've found a way to temporarily raise the needles. I've taken the locking springs out and put spongy foam thingies under the needles so they are raised as much as they can technically go up, the foam goes down only as much as it being pushed down by the locking, twist in plastic bit - I might actually draw a picture for that for you to understand. Anyway the needles went up for about 1,5-2mm and.... AFR is spot on if not on a bit of rich side (12:6-15:1) with that dip in AFR going completely lean around 3000-3500rpm and right back up to normal.

The thing is there's noticeable change in how it revs and pulls now. It's much slower and weaker then before with needles lower down and choke on. Why is that? Is it because of added weight inside the slides? I don't understand that at all...

If anyone has got any clues what causes it to suddenly go lean at that short rev range and also why did it became so weak now when it seems like it's running sort of fine finally, please let me know.

Thank you very much,

Tom

Just caught up on this thread. Are you sure the manifolds to head joints are intact and not leaking. I run a 2 litre Black Top in my single seater, fitted with R1 carbs and fired up with Megajolt. Fortunately this carb accepts Weber main jets so messing about drilling. I use Weber 180 mains and modified air correction jets with the needles lifted 1 notch. Weber jets are measured in mm. so a 180 jet is 1.8mm and would be the size of drill to open up a smaller jet. Fortunately I had lots of jets in stock and simply stuck 4 x 180s in then to RR for final set up. I use a small solid state fuel pump and have the regulator set at 3 and it has never been a problem. I use a Pipercross air filter with a back plate supplied by Danst Engineering, who also supplied the manifold. My carbs are on original centres and haven't been respaced. Dan cuts the new back plate to the correct size for the carbs. The RR man I used was also a Weber specialist so had hundreds of dgv type jets if they had been required and to save buggering about with number drills.....

I've managed to raise needles using specially shaped small washers.. The only difference from stock now (except the height of them) is that the're not pushed down by a spring but have got about 1mm of free play. Don't know if it affects the performance at all. I've got 150 jets at the moment, needles raised about 3mm and air screws undone couple of twists. The strange dip in AFR is gone and car pulls nicely throughout the entire rev range with good/acceptable AFR... I can definitely feel the improvement over the stock now, but it doesn't pull as hard as it did with stock needle position and choke on. Could it be because the choke on one of four carbs i've got is actually broken and it had extra power because it was going lean on one of the cylinders before? I mean I'm happy with how it runs now and I could probably leave it like this, but if there's more to be squized out - I want it!

So yea - '150 jets, stock needle position, air screw out couple of turns and choke on because it's lean as hell without it' gives more power/torque then '150 jets, needle 3mm up, air screw out couple of tunrs and choke off with good AFR all the time'

Could anyone explain?

Cheers,

Tom

Have you tried blocking the air correction holes this is to stop the carbs going week at higher revs some carbs like this and some don't
If you block them you may not need to use the chock

I think that if all is right with choke on, you need bigger main jet...

It's not that. I haven't changed jets, just raised needles and air/fuel ratio is good now, just like it was before with the choke on. For some reason it felt more powerfull before. Although now it runs quite nice actually, biggest improvement is that it pulls strong right from the bottom with smooth power curve, before it was very slow at low revs and it would pick up more oomph at higher revs... I might actually leave it as it is.

Also had some fuelling problems yesterday on my way back from friend. The fuel wouldn't go through. I barely made it couple hundred yards and then it stalled and didn't want to start again. No idea why. Pulled off air filters, pulled off fuel line... there was fuel in the line so I've put it back on. I thought that's my fuel pump gone but I've managed to start it. It ran very rough at first with the choke all the way up (usually it floods the engine this way) and let it run for a minute or two. Pump was running ok and everything seemed fine... After then it worked like nothing happened - it ran spot on again... No idea what that was...

[Edited on 13/8/13 by spuker1]

It seems to me that you are having a really bad time with these carbs and shouldn't be. I reckon you should either totally strip those carbs and rebuild them or get a set that are known to be good. R1 carbs are brilliant, mine cost me £85, a manifold from danst and I used 4 small tubes to balance the vacuum for the MAP sensor, though Danst can supply a proper balance tube.This thing goes like stink. I never have to use the chokes, full throttle and press the button, though I do use an external power pack. The use of any restrictive device at all is wrong and indicates that you are short of fuel, nothing else and it is extremely bad practice to do this to increase the afr. The use of wire mesh filters was o'k back in the day, but you must never have them/it closer than 4"/100mm. With the R1 carbs you must also use the original rubber trumpets for the best results. You can re use the 200 jets you have by soldering up and re drilling......................

Cheers,

I've managed to lift the needles a bit and it's perfectly driveable now but still on the rich side. I think If I go down from 150 to 130 jets on current needle setting it will be spot on. All the restrictor stuff was just a temp job so I could get the car to the local meet. It's in the past now and I'm not getting back there. Unluckily last time I took my baby out, it was running sweet and I had a blast in it, the fuel pump went (I've been told haven't I? ). I'm going away for holidays soon so as soon as I get back I'm going for a facet fuel pump and smaller jets an it will be all done and wrapped up.

Also, the underpowered feeling with raised needles was because when I've raised them I had to take little springs that hold needles in place out. They have a slight play in the diaphragm slide so when they hit the petrol in the bowl they didn't do it as hard as with the spring locking them in snugly. Springs are modified and back in now and it runs sweet without any choke or anything like that.

The carbs themselves never gave me too much trouble is just getting the right tune is a sort of hit and miss/try and test thing. I never did it before and I'm learning while I'm doing it.

Thanks

[Edited on 3/9/13 by spuker1]

quote:

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Originally posted by spuker1I'm going for a facet fuel pump

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Thanks! I've got a FPR on already though so it's not an issue really.

Also I think bike pumps are quite simillar to what I'm looking at. Check it out:

Facet 12v Low Pressure Posi-Flow Electronic/Electrical Fuel Pump Kit

"The Posi-Flow Fuel pump is very common on tuned and motor sport cars upto 180BHP. The typical application would be an engine fitted with a large twin choke or twin carb's on a smaller engine. Flow rate is 32 USgallons per hour."

[Edited on 4/9/13 by spuker1]

I'm sure that pump would work, but the bike pump is still the best for bike carb's as it cuts out automatically when it reaches the required pressure

the facet type ones are designed for webbers etc which have different needs....

I am using a small solid state pump with my R1 carbs and have no trouble at all yet. The same pump was also used to fuel the 32/36 carb on my 1600 x flow.....

Why buy something that may work when you can get the correct item for a similar price? Bike pumps regularly go for £20-30 on ebay.

Stu

I think whichever pump I'll go for it's going to be fine anyway.

Thanks

quote:

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Originally posted by spuker1
I think whichever pump I'll go for it's going to be fine anyway.

Thanks

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Ok I think I came to the point where I can finally say that my car is actually running bike carbs, so to sum it up:

My bike carbs conversion project had it's ups and downs with the most recent one where the car stopped fueling itself and cut off miles away from home and I had to be towed back. I thought that the 30 year old membrane fuel pump went but when I took it out for inspection it squirted petrol all over the place so that was definitely working well haha. Turned out to be my fuel pressure regulator, which I bought brand new just for the conversion (off eBay of course). It sort of jammed itself off and didn't let any fuel through. Bypassed that and it works like a charm now.

I've also struggled with getting right fuel/air mixture. Mainly because with the carbs I've used there's no needle height adjustment so I had to fabricate like tiny tiny washers that would go between the needle head and the bottom of the inside of the slide (if that makes any sense). Obviously that took absolute ages to get right. At first I had them farily hight and to do that I had to take the locking springs out, which ment the needle would have about 1mm play. That gave me fairly lean mixture still, so I've managed to squeeze the springs back in and that went rich through the roof. So I've made like small washers and left springs in and now it's just about right, still slightly on the rich side. So I probably have to downsize the jets from 150 to like 135 or/and tweak air screw as that affects entire range not just idle/slight throttle in my carbs. Also considering going bare trumpets for extra oomph. Not sure what negative effects could that have though, I don't want to hurt my engine...





But anyway, Thank you all for the massive support and all good advice! I think I sort of know what I'm doing now and the conversion is pretty much done, now it's just fine tuning and making it look nice

All the best!

Tom

[Edited on 23/9/13 by spuker1]

quote:

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Originally posted by spuker1Turned out to be my fuel pressure regulator, which I bought brand new just for the conversion (off eBay of course). It sort of jammed itself off and didn't let any fuel through.

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quote:

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Originally posted by spuker1Also considering going bare trumpets for extra oomph. Not sure what negative effects could that have though, I don't want to hurt my engine...

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Can I ask a question? Have the bike carbs actually made any difference to the performance or driveability of the car over standard? Sounds like a huge amount of grief for little return at the moment to me...? I admire your efforts but I've read some proper horror stories about the amount of time and money people have invested in getting them to run properly on cars. Surely a set of Webers or Dellortos would have been easier?

quote:

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don't do it !! running without filters will shorten the life of your engine


your individual filters aren't great for performance, but they are better than nothing

if you want better performance than your current setup then use either a foam sausage filter or an airbox ducted to a good cone filter (think something like the pipercross airbox's, but you don't have to buy anything that expensive - its only a box!)

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quote:

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Can I ask a question? Have the bike carbs actually made any difference to the performance or driveability of the car over standard? Sounds like a huge amount of grief for little return at the moment to me...? I admire your efforts but I've read some proper horror stories about the amount of time and money people have invested in getting them to run properly on cars. Surely a set of Webers or Dellortos would have been easier?

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quote:

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Originally posted by spuker1
What about trumpets with those dirt bike style foam socks on?
or Weber style mesh like this?

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Awesome! I'll go with that then, when I save up! I've already ordered a set of trumpets that look like they going to fit my carbs right in!

Excited!

Hi!

Another little update! I've put a set of bare trumpets on my carbs and didn't that make a difference!!! It leaned it out a bit so the AFR is absolutely PERFECT now and by perfect I mean that the gauge reads AFRs in exactly same way as it did on the stock carb. The improvement in performance is even more now. The car flies. It's still not fast at all by being a 1.3 but when I took my friend around to tell me how it is he said 'not bad for a 27 years old 1.6 single cam' obviously at that point I went 'ohhh yea!!!!!'

Here's the shot from yesterday's local meet:



The car will be going off the road for the winter so I'll have enough time to get an airbox or the sausage filter on.

Thanks again guys!

Regards,

Tom

Looks tidy, glad you got it sorted.

Take care

Rich

Check out the recent video of my car!

http://www.youtube.com/watch?v=7Dx3RqXauEg

[Edited on 7/10/13 by spuker1]

Great movie man!