1987 ford pinto engine 2.0 and weber 32/34 carb issue?

[Blooka]

Hi
I have a tiger kit car with a standard 2.0 pinto engine fitted.
Im having a few problems with misfires and odd backfiring under acceleration.
I have checked usual things float height, timing, plugs, ht leads etc. with no luck.
It has a 32/34 dtml carb fitted I was just wondering if it is jetted correctly.
I am going to upgrade at sometime to a better carb but for now just wanted to use this if its ok.
the jets in it are

primary idle 55
secondary idle 60

primary main
air 165
emulsion f30
main 125

secondary main
air170
emulsion f22
main 117
does this seem ok for this engine tried trolling the net but i cant find anything
hope someone could help me just want to cancel this out befors delving deeper lol
many thanks
Dave

[stevieturbo]

And have the jets changed since it last ran correctly ? in order that they may be right or wrong ?

[Blooka]

I have only just bought the car so not sure if they are right or wrong
cheers

[Scrump]

If I recall correctly from my time with Pinto engined capris and cortinas many years ago, that carb has an issue with wear where the throttle spindle enters the carb housing. This allows movement of the spindle which causes an air leak when the throttle is opened.
I remember climbing over many fords in scrapyards and checking the play in the throttle spindles to try and find a good carb.

[stevieturbo]

Peter Burgess might be a good man to speak to if he sees the thread.

or do some of the old Haynes manuals give jet sizes for various applications ?

[PaulKemp]

You can’t re-jet a carb by guesswork and it’s unlikely the card jetting has changed from standard. The carb you have is not ideal with a vacuum secondary and a water autochoke which never worked well.

What air filter is strapped to it? You may have restricted Airflow due to a thin flat filter or proximity to the bonnet.

A gas analyser test would show what the mixture is doing, checking ignition timing will give a baseline

Edited by PaulKemp on Sunday 31st May 09:56

[PeterBurgess]

Thanks Stevie but I can't really help as I tend to tune carbs like that infrequently so just change jets on the day and don't really remember what I have done. I think Paul is right, no point guessing. Maybe the safest option is to take it back to whatever standard jetting is and fit a standard airfilter system if possible as it is usually the change from a std to a K&N/foam set up that has the most effect on jetting requirements by reducing the flow restriction which then lowers the pressure drop on the jets which makes it run weaker.

[kev b]

I recently rebuilt a similar carb from a Westfield, it had run ok since the owner built it in the early 1980s but after winter layup started running badly.

When the carb was stripped down the accelerator pump diaphragm in particular was as hard as rock, in fact all the rubber components were shot. Fitted an overhaul kit and gave it a good clean and it runs a treat now.

Good point about the butterfly spindle leaking, you can put a blob of thick grease on the spindle which will seal it temporarily to see if there is a problem.

[Little Pete]

kev b said:

I recently rebuilt a similar carb from a Westfield, it had run ok since the owner built it in the early 1980s but after winter layup started running badly.

When the carb was stripped down the accelerator pump diaphragm in particular was as hard as rock, in fact all the rubber components were shot. Fitted an overhaul kit and gave it a good clean and it runs a treat now.

Good point about the butterfly spindle leaking, you can put a blob of thick grease on the spindle which will seal it temporarily to see if there is a problem.

A carb overhaul, particularly the pump jet diaphragm, is a good call.
If the car has been off the road for a while it could be worth cleaning out the fuel tank and lines and fitting a new filter also. Take your time and work through everything methodically.

[Blooka]

Thanks for all the in fo guys.
spindle doesnt seem to have any slack in it so I
have ordered an overhaul kit and hope that works
This is the air filter Paulkemp for the car does it seem ok for it?
Also gonna put it back to standard jetting if it already isnt, does anyone
know where i can find a website that tells me where i can find this info?

thanks again all

[ndtman]

Is it just the photo or is the engine nose down as that would screw up your float levels/fuel delivery?

[Blooka]

no its jacked up
having to change water pump also

[kev b]

Before changing the jetting, does it have a standard cam and is it an original spec carb.

Back in the day boy racers would swap carbs about thinking they would gain power meaning many Fords ended up with the wrong carb fitted, one of my mates used to fit 3 litre Granada or Capri carbs to his four cylinder Fords ‘cos “its from a bigger motor so more power”

I think this may have been the case with a cam and manifold swap after a rolling road tune but just bolting on any old big carb wasn't a good idea.

[PeterBurgess]

Standard jetting with standard air filter assembly. If there is richer than std primary jetting it may have been set on a rolling road. If it is std primary jetting it is likely you will need richer jetting.

[HughG]

Has a pipe been removed from the T-piece coming off the inlet manifold?

A leak like that will likely also effect pressure across the carb.

[HughG]

And (only very slightly related) I still have the spare jets I bought when I was going to try and setup the Delorto DHLA 45s using the lamba sensor on my 2.1 pinto. I gave up and got Gerald Dale to do it in the end. If anyone needs the jets I'll post up what sizes I have and if suitable can post, better someone uses them than they sit in my toolbox for another decade.

[PaulKemp]

Filter is not ideal it has a much smaller surface area to the standard large circular paper filter.
A full foam filter would be better but proximity of the top of the filter to the bonnet may negate any gain. There are bolt on low profile adaptors that allow you to use an air feed pipe from a cone filter in the nose of the car if you don’t want to cut the bonnet.
To check if it is an air filter restriction just take the filter off and try without for a short time.

[mike_e]

I had a very similar air filter and carb on my Pinto powered kit, it was never very happy running such a small pancake filter and come winter time it caused the carb to ice up quite severely and stalled the engine. Try a stock air box and filter if you can find one.

Also check fuel flow/pressure and any in-line filters, blockages can sometimes lead to a mis-fire under acceleration.

As mentioned previously and I could be wrong, but it looks like the Servo vacuum hose is missing, some lightweight kits don't have brake servos and it'll run like a pig if that's missing or not capped off.

[LimSlip]

The maxim "95% of all carburettor problems are ignition" should be borne in mind. A bad coil or condenser (if running points) will invariably start breaking down under acceleration first.