42 DCOE Weber on 1800cc Golf EX engine - Questions!!

Good morning all,
Can anyone help me with my current project, I have questions?
Has anyone on here ever done a SINGLE DCOE Weber set up on an EX engine car?

I have recently changed the head / carb and exhaust manifold/system on my 1991 Mk1 Golf Cabrio / Clipper EX engine type.

The actual specification is:

1991 Mk1 Golf Cabriolet/Clipper 1800cc carb EX engine
Now has fitted TSR Pack A head, 270 degree cam, Lynx Manifold and single Weber 42 DCOE, Stainless Steel 4 in 1 Manifold and system.

Q:Will the standard mechanical fuel pump be sufficient?
Q: Do I need a fuel pressure regulator or a stand alone new electric fuel pump? (I actually have both, but not yet fitted either)

The car starts, idles and runs great while standing still, (Sounds amazing, not too loud, just a great induction noise)
However when driven it pops and stutters and coughs before finding its groove and pulling like a train.
My concerns are of course that it is not running correctly or fuelling right.

Any advice would be very very welcome.
If there is anyone local to Peterborough who could set this all up properly, I am happy to pay for the service?

Thanks all
Best regards, Kev.

Hi Kev

Sounds like a basic carb jetting issue.

The Lynx manifold is pretty poor in terms of fuel & air distribution so wont make the best power, but it can be made to work.

If you can tell me the choke size and the current jetting spec I can help you get it right before you hit a rolling road.

Carbs dont need much fuel pressure…2.5-3.5psi is fine, as long as the std pump will deliver that consistantly you'll be ok.

Get a list of the jets…the main ones you'll need for now are under the bit butterfly nut in the middle…you'll find two pairs…the long assemblies are the main power jets…emulsion tube, main jet & air corrector…the smaller pair are the idle jets…they will have a marking on them like 45F8 or 45F11…need to know what they are to start with and the main choke size in the barrell/carb body.

The basic idle screws could be out too…with the engine off, turn both idle screws…the ones with small springs under them…all the way inwards until they just stop…dont force them!…then back out 2 full turns each and start it up…turn each screw inwards or outwards a 1/4 turn at a time intill the idle faulters or gets better…do one at a time then go back to the othet to see if you can make it better…you may need to rasie or lower the idle speed to balance it out each time.

If the idle jet size is correct the screws will end up between 1-2 full turns out. If its set there and the engine is hesitant to drive until you give it a bootfull then the jets are wrong to start with.

Get the above details and post it up and we can go from there kev.

I remember reading some tests done by david vizard on the lynx manifold,( many years ago and not on the golf engine), and he reckoned the lynx was practically as good as twin side draughts until the upper rev ranges.

They can work well on mild road spec engines but yes certainly nothing like as good as a pair of side draughts on higher spec engines.