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Can carbs be used as throttle bodies?
whitestu - 4/12/08 at 02:38 PM

Assuming I could get it all to fit together, what would stop me using a set of respaced bike carbs as TBs mounted to a modified [i.e cut down so it is effectively a flat plate] Zetec plastic inlet manifold, using the standard Zetec fuel rail and injectors that are part of the manifold.

All the bike carbs will be doing is opening butterflies to control air flow and giving a TPS signal.


Stu

trogdor - 4/12/08 at 02:47 PM

no reason, its just that carbs have a venturi in them that will now be acting as a restriction to the air flow. But beyond that there is no other problems. As far as i know that is!

Mal - 4/12/08 at 02:58 PM

If the carburettors are DCOE ones the venturi can be removed.

stevebubs - 4/12/08 at 03:19 PM

nothing - and IIRC there is such an example in Dave Walker's Injection book...

tim windmill - 4/12/08 at 03:44 PM

yep can be done a fellow mk owner has bikes carbs (not sure which ones) and runs fuel injection on a 2.0l zetec

BenB - 4/12/08 at 03:58 PM

As mentioned the only downside is the unrequired venturi. Get rid of that and they're not a bad option.

Main downsides are the fact that unlike quite a few TBs, carbs won't have a TPS already and you'll need to attach the injector boss etc etc....

coozer - 4/12/08 at 04:01 PM

Interesting.. but, how do get rid of the slides? Obviously if you take them out there will be a huge gap.

austin man - 4/12/08 at 05:53 PM

Brother in law has 2 ltre zetec with injection and blackbirs carbs, all we did was removed the cover on eac carb along with the spring, raise the slide and glue ? seal the slide at its highes point. Dave Walker did the mapping and didnt raise any concerns

whitestu - 4/12/08 at 07:26 PM

It was bike carbs I was planning to use, so no venturis.

Don't some bike TBs keep the vacuum slide? I'm sure early R6 TBs are like this.

Stu

[Edited on 4/12/08 by whitestu]

paulf - 4/12/08 at 09:07 PM

I have noticed that most R1 and R6 throttle bodys have the vacuum controlled slide.This may be an advantage as it will help to get a good map signal at part throttle, the gsxrs have a secondary butterfly driven by a servo motor which does a similiar thing but is normally removed as there is no easy means of controlling it.
Paul.

quote:
Originally posted by whitestu
It was bike carbs I was planning to use, so no venturis.

Don't some bike TBs keep the vaccum slide? I'm sure early R6 TBs are like this.

Stu

tim windmill - 5/12/08 at 04:38 PM

my r6 throttle bodies have still got the vacuum slides and work very well

Schrodinger - 5/12/08 at 08:52 PM

I did just that with an old pair of dcoe 40s