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dellorto dhla 40 good for 2.0?
blakep82 - 9/8/14 at 11:07 AM

Having real problems getting bike carbs to work, mainly due to the angle the need to sit at, which is a major problem, since ive spent so much on parts manifold etc, but they just keep leaking...

Theres a pair of dellorto dhla 40 carbs on ebay, needing a clean, but are currently cheap with not long left.
Good idea (just to get moving on this car and getting running reliably withing pissing fuel out) or bad idea?
I can, and intend to come back to bike carbs later as I prefer them, but to buy another set of bike carbs is about 3 or 4 times the cost these dhlas are at just now

The manifold is from fastdan, I wonder if some kind of dhla adapter is possible?


BaileyPerformance - 9/8/14 at 11:28 AM

can you post some pics of your install?

strange you cant get the bike carbs to work.

dellorto 40s will work fine on a stock 2.0L but you will need to get them jetted.

if you plan on buying some new you may find its better to go megasquirt as its wont cost much more to EFI

if you have found some used carbs, be carful, inspect for damage and wear in the spindles


blakep82 - 9/8/14 at 11:34 AM

Description
Description


I just couldn't get the angle I needed, and I thought the leak was due to valves needing replaced, which I did, and cleaned the seatsbest I could, and tried to set the floats, but its no better

Theres a pair of dhlas for 56 quid just now, 25 minutes left. I expect they will go up, but I'm thinking a clean up and they could go back on at worst.
Shouldnt be too difficult to make an adaptor to fit them on the bike manifold I reckon
I just need it working, and can come back to re try bike carbs later


BaileyPerformance - 9/8/14 at 11:47 AM

if thats a rally car dont go for dellortos or webers, neither like been knocked about.

seems to me your correct, its the angle thats wrong.

we did a talbot sunbeam rally car with an ecotec in it, standard inlet manifold with megasquirt - it made 155BHP


19sac65 - 9/8/14 at 11:56 AM

Very unusual
Have you cleaned and checked the float valve isnt sticking
What fuel pump are you using, bike carbs only need 2psi
If theyre set nearer horizontal than 30 degrees then it might be a little rich but still shouldnt pee out
I changed my angle from a level float gasket to nearer horizontal for clearance issues and it just made the plugs a little darker
It could cost you far more to rebuild,re choke and jet the dellortos
Then theres a manifold and set up
And you still end up with old fashioned fixed choke carbs
From my experience the bike carbs need a bit of messing to get right bit theyre much better from then on
Smoother pick up
Idle at 7-800
Dont go out of tune every 5 minutes
Dont the garage stink of fuel

Stick with them,theyre worth it
What carbs are they ?
Where abouts are you


blakep82 - 9/8/14 at 12:10 PM

Didnt get them anyway. The ad wasnt giving much info, they were filthy, and said they'd been sitting, so only wanted to put maximum of about 60 quid, put 61.74, highest bid then out bid with seconds to go.

In that case, I guess these zx9r e carbs are coming back off, getting completely stripped and cleaned, and see how they go. I'm sure they're overfilling though, but I just can't see how to stop them.
The floats have stops to stop them dropping down too far, and the valves are set so they should close as soon as they move
Fuel pump isn't a bike pump (gasp!) But is a facet with a regulator set to 1.5psi.

Stephen bogg says to take it off the manifold, hold at an angle and sett if that stops it pissing out, and that'll tell me if the valves are at least working

I'm in greenock, scotland

[Edited on 9/8/14 by blakep82]


redturner - 9/8/14 at 01:15 PM

Set at that angle they are never going to be right. I run a set of R1 carbs on a Zetec in my race car, on a DanST manifold fed from a Facet pump with the regulator set to 2.5 lbs. Never had a leak yet. They are designed to run with the float chamber level but it looks like you could have an issue with the air cleaner.....


Norfolkluegojnr - 9/8/14 at 01:38 PM

Presume you are sung a bike pump?

On my zetec install I tried bikes carbs with a car pump and pressure reg, could never get it right.

Switch to bike pump, no problems.


Paul Turner - 9/8/14 at 04:31 PM

quote:
Originally posted by BaileyPerformance
if thats a rally car dont go for dellortos or webers, neither like been knocked about.



Back in the days before injection all rally cars use either Webers or Dellortos and they worked just fine.


JMW - 9/8/14 at 07:07 PM

Getting Dell'Ortos or Webers second-hand, you definitely need to know what chokes are in them as these effectively 'size' the carburettor, and having to buy 4 to suit your engine will add significantly to the cost. Jets much less so (in terms of cost), but will probably also need to be changed to suit your setup.

I wouldn't buy either of these carb.types without knowing the choke sizes.


BaileyPerformance - 9/8/14 at 07:14 PM

quote:
Originally posted by Paul Turner
quote:
Originally posted by BaileyPerformance
if thats a rally car dont go for dellortos or webers, neither like been knocked about.



Back in the days before injection all rally cars use either Webers or Dellortos and they worked just fine.


No, not really, thay where used because there was not much else available.
We have setup webers on all sorts of cars, in the past just as an experiment we ran a pinto on 45s on static dyno load, monitored fuelling, then banged the top of the carbs, fuelling changed by one whole afr point for a second then returned. Fuel frothing is also an issue due to engine vibration, most if which can be avoided if carb mounting is correct but not all.

I'm sure your right, carbs could be made to work, but what's the point when fuel injection is cheap now :-)


blakep82 - 9/8/14 at 08:17 PM

well, i took them off, set them at the angle they're supposed to be at, and they still over filled, and petrol dripped out the back of them. couldn't actually see what hole it came out of though.

so started to strip them all down anyway. did one, everything looked clean enough, no reason to think the others would be dirty. i'll take all the needle valves out, get a small wooden dowel and twist it in the seat to sort of polish it up a bit. re set the floats so they pretty much close as soon as possible (hopefully there'll be enough fuel to not go lean) and see what happens.

i'll need to get a bike pump too i suppose.

failing all of that, either a set of mikuni's which have flatter bowls, but need to have the same spacing and tps... tall order

or, EFI... i'm tempted to finish the rest of the car, wiring and everything, then get someone, maybe someone on here? to just take it and install megasquirt, and i'll pay them for it. i just don't fancy trying to install it...

so, to help with the decision, who can tell me ALL about megasquirt, or any other efi controllers. i've already spent a lot of time and money on megajolt, so reusing as much of that if possible. is there a megasquirt, injection only controller?

i was thinking i was nearly finished, then this. now, i just want this car done

[Edited on 9/8/14 by blakep82]


BaileyPerformance - 9/8/14 at 09:18 PM

U2U sent, have a look at what we do, we can offer megasquirt as a turnkey conversion, push in drive out!!!

Www.facebook.com/baileyperformance

Have you still got the vauxhall inlet manifold and injectors?


19sac65 - 10/8/14 at 06:31 AM

I still recon its fuel pressure
Have you set the regulator with a gauge or relied on the marks on it
If you think about it they shouldn't leak if not at the optimum angle-bikes are not always in one position
Think cornering,accelerating and wheelies !!
I dont know of a bike that throws fuel everywhere when the front wheel lifts


Norfolkluegojnr - 10/8/14 at 08:07 AM

quote:
Originally posted by blakep82
well, i took them off, set them at the angle they're supposed to be at, and they still over filled, and petrol dripped out the back of them. couldn't actually see what hole it came out of though.

so started to strip them all down anyway. did one, everything looked clean enough, no reason to think the others would be dirty. i'll take all the needle valves out, get a small wooden dowel and twist it in the seat to sort of polish it up a bit. re set the floats so they pretty much close as soon as possible (hopefully there'll be enough fuel to not go lean) and see what happens.

i'll need to get a bike pump too i suppose.

failing all of that, either a set of mikuni's which have flatter bowls, but need to have the same spacing and tps... tall order

or, EFI... i'm tempted to finish the rest of the car, wiring and everything, then get someone, maybe someone on here? to just take it and install megasquirt, and i'll pay them for it. i just don't fancy trying to install it...

so, to help with the decision, who can tell me ALL about megasquirt, or any other efi controllers. i've already spent a lot of time and money on megajolt, so reusing as much of that if possible. is there a megasquirt, injection only controller?

i was thinking i was nearly finished, then this. now, i just want this car done

[Edited on 9/8/14 by blakep82]




Fit a bike pump first, then reassess. Honestly I messed about for ages with pressure regs, but the bike pump solved my over filling issue.


alfablack - 10/8/14 at 08:08 AM

They look to be sitting at the wrong angle which is why you can't stop fuel piddling out.

also factory rally teams believe it or not used to run carbs in competition

and there are other programmable ecu's on the market should you wish to spend even more money some better value.?

but i would persevere check the angle the carbs sat on the bike they came of so the float bowl sits level have the tubes altered to match this and as long as you have altered the linkage ratio's they should be fine