ZX6R / R6 ones (or similar) should be plenty big enough for any 1.6 pinto
I have a 1.6 Pinto, complete with downdraft carb from the donor Sierra. But i'd rather not have a hole in the top of my bonnet, so have been
looking at side draft carb options.
A pair of twin Webers seems to be extremely pricey - I've seen people wanting c. £500 for a set. But I guess would largely bolt straight on, and
work from the existing fuel pump/ignition system, etc?
I do have a set of bike carbs that I got with my build- but am not clear on how much additional kit (other than the manifold) I would then need to buy
to get my engine running with them? Would I need to change the ignition system (it currently has vaccum advance on a distributor), would I need both
high and low pressure fuel pumps (and not use the Pinto mechanical pump), would i need to have a fuel swirl pot in the engine bay, could I still tap
the crankcase breather into the inlet manifold - or would I need an oil catch tank too?
Any advice appreciated!
[Edited on 14/5/20 by jps]
On the induction front you just need a manifold of some description and a bike fuel pump.
If you need a vac takeoff for the dizzy you will need to ensure you get a manifold that has this.
Bike carbs are way easier to set up than what will probably be an old set of Webbers.
webbers like to drink like a fish and need constant tinkering, the sun goes behind a cloud and they go out of tune.
better to use bike carbs or bike injection, there is plenty info on the interweb about the conversion
Can I suggest you contact Bogg Bros, tell them what engine you have and send them your old bike carbs, they will make manifold, supply gasket, air-filter, back plate, fuel pump, etc and set up your carbs to suit the engine. I did this and still have same carbs on my 1.8 zetec engine after 12 yrs and not even had to touch them since fitting. I am running Megajolt for the timing advance. Probs cheaper to do this all yourself mind.
"webbers like to drink like a fish and need constant tinkering, the sun goes behind a cloud and they go out of tune. "
I totally agree with Conrod, webbers are for race engines and be tuned on a daily/weekly basis,
Mine that were given to me, had to be balanced and tuned every time before I drove the car, and did about 15 mpg
a nightmare with a 6 gallon tank!
I sold them on ebay, genuine matched 1960's twin 40's, I got over a grand for them,
On crossflows they did a Siamese manifold, so you could have just one twin 40 feeding all four cylinders, that could be an option,
or just build a bulge, like I had on my car, its easy, with a mud mould and some fiberglass
pics in my archive
steve
I am close to you but shielding that said I have some experience with both Pintos and bike carbs and currently have a set that I considered to small for a 2.0L which may be just right for a 1.6
as I remember...
webbers are great when they are spot on, but thats like never,
su are really good when they are spot on, but when they are just close they are still good
You can fit bike carbs and keep the distributor but may need a low profile distributor cap.
You will probably need a catch tank.
Bike carbs only need 1.5psi so the manual pump may overload the bike carb float valves, you can use 1 low pressure pump from the tank and a fuel
pressure regulator, swirl pot is advised if you don’t have a tank with a sump and that would require 2 pumps.
Manifold can be tapped for vac takeoff
Bike carbs need a specific manifold made for them as they have different spacing
Bike carbs are variable venturi so better in most cases as the engine draws the slides up on demand
When you get a chance tell me more about the bike carbs and I can compare with mine on a 2.0L
You biggest step to more power is to fit a 2.0L
I'd agree that Bike carb's provide the most cost efficient route and when correctly set-up they work and stay in tune very well
Just for some balance though (excuse the pun) Correctly rebuilt and set-up Webers can be made to work very well (and stay in tune)
My old 2 litre Zetec on twin 45 DCOE's and Weber Alpha ignition would pull from 25mph in 5th
(Admittedly they did have the five progression hole modification)
As above assuming you don't want to spend the £££ one EFI then Bike carb's are what you want
ZX6R / R6 ones (or similar) should be plenty big enough for any 1.6 pinto
quote:
Originally posted by jps
I do have a set of bike carbs that I got with my build- but am not clear on how much additional kit (other than the manifold) I would then need to buy to get my engine running with them?
quote:
Originally posted by jpsWould I need to change the ignition system (it currently has vaccum advance on a distributor)
quote:
Originally posted by jps
would I need both high and low pressure fuel pumps (and not use the Pinto mechanical pump)
quote:
Originally posted by jps
would i need to have a fuel swirl pot in the engine bay
quote:
Originally posted by jps
could I still tap the crankcase breather into the inlet manifold - or would I need an oil catch tank too?
No need for a catch tank. Just tap the crankcase breather into the air filter back plate.
Also, with a wideband O2 set up you can easily tune bike carbs at home if you want.
Thanks everyone for the responses, much appreciated. In the first instance i'm going to get the car running with the downdraft carb, but from there I am reassured it's very doable, and not too expensive, to use the bike carbs.
Don't underestimate the amount of work involved in fitting bike carbs! I did...
My linky (extract from my website)
Mind you, I did everything, including making the manifold (apart from the welding, which was done by Mr 907). If you buy a manifold then the workload
goes down a huge amount. Still not trivial though...
quote:
Originally posted by David Jenkins
Don't underestimate the amount of work involved in fitting bike carbs! I did...
My linky (extract from my website)
Mind you, I did everything, including making the manifold (apart from the welding, which was done by Mr 907). If you buy a manifold then the workload goes down a huge amount. Still not trivial though...
Absolutely right! I think that I confessed my fussiness at the end of the web pages...
However, if you're making your own manifold then it's easier to respace the carbs IMHO - the shapes of the pipes in the bought manifolds are
downright scary!
[Edited on 15/5/20 by David Jenkins]
quote:
Originally posted by David Jenkins
Don't underestimate the amount of work involved in fitting bike carbs! I did...
My linky (extract from my website)
Mind you, I did everything, including making the manifold (apart from the welding, which was done by Mr 907). If you buy a manifold then the workload goes down a huge amount. Still not trivial though...
I made my own inlet for my Xflow when I converted to injection by using an ally plate (12mm?) onto which I laid a gasket then marked the plate using a scriber , drill a hole where each port was and then cut roughly to shape using a wood working coping saw and plenty of cutting fluid.Way quicker than chain drilling, filing etc. It took about an hr to roughly cut to shape , the inlet runners I turned up from a piece of ally bar before getting it welded, again using a head to minimise distortion. When unbolted from the head there washers some distortion so I placed wooden blocks between the head and manifold and tightened the retaining bolts to “pull” the manifold nearer straight then a very light lapping using a sheet of emery and a surface plate. Final job was to match the ports with the head. Total cost was around £20? for the complete manifold
quote:
However, if you're making your own manifold then it's easier to respace the carbs IMHO - the shapes of the pipes in the bought manifolds are downright scary
quote:
Originally posted by jps
Thanks David - I had looked at your site, and having considered I was going to buy the manifold (Bogg Bros or similar) and not respace the carbs, it did seem it might simplify somewhat.
I think longer inlets give more torque theoretically. 7s are very light so torque usually isn't lacking. My manifold is very short and seems to work ok.
I think longer inlets give more torque theoretically. 7s are very light so torque usually isn't lacking. My manifold is very short and seems to work ok.
a pair of decent 40ies dellortos will cost you 160-180pound....you should buy some with 28 venturis for your 1600 engine...than you need a manifold
with gasketset for twin 40ies (all have the same stud pattern: dellortos dhla, solex addh and weber dcoe), throttle linkage and air filters.
depending on the length of the manifold you will finally end with a hole in the bonnet as well, not on top, but on the side.
from the technical (tuning) point of view, a 1600 pinto does not profit at all from sidedraugts.