Running Rich

[Guest clive5550]

Hi all I hope someone can help im running a 2ltr pinto with a piper fast road cam and twin weber 40s, I've got them set with 36mm chokes 145 main jets and 190 air jets. The car is running very rich with black smoke and black plugs, it don't like driving on low revs and is only happy when driving hard, its returning about 18 mpg on a run. Im considering getting a twin choke carb or similar and ditching the twin 40s I know there is the bike carb option but finances wont allow that ! anyone got any ideas please Clive.

[Snapperpaul]

Sounds like idle circuit not main jets

Its worth looking at idle air screws

If you haven't got a wideband lambda then your really only guessing

Rolling Road time

[lockyer89]

Don't say that! lol I've just put swapped my bike carbs for some twin 45's. I have noticed mine running a little rich too, it's not on the road yet, but when running it in the garage, plant the accelerator and it will spit before it picks up. Will be booking in for a rolling road once I've run the engine in as it's a new head and camshaft.

 

If you change your mind with about the bike carbs I took off some Zx6r bike carbs, along with the pinto manifold - looking for £100...

[speedtripledan]

Rolling rd, there is no other option if you ever want it to be right. Webers can be tuned to work on any engine that's why there are so many options available. My 45s on my 2.0l zetec run 36mm chokes and 140 mains it runs as smooth as a production car and stays in tune also returns 30 mpg + let alone goes like stink.

[Guest clive5550]

Well folks snapper Paul did it again ! it was the idle jets, I've put in a smaller set, sorted the mixtures and the car runs a dream it's totally transformed it thanks Clive.

[Peter Bell]

You might find this a useful read Clive.

http://www.s262612653.websitehome.co.uk/DVAndrews/webers.htm