Lean running high compression engine/carburettor

[leggattr]

First of all the engine is a 14nv with 13 head and Weber 32/34 dmtl.

So I’ve been at the last stages of getting the nova mot’d but having some problems with consistent running. Basically It idles fine and accelerates fine when standing. What I’ve noticed is after a run or 2 up and down the street I’ve found the carburettor surging/bogging down on every press of the pedal.
After speaking to a mechanic I know he thought it could be a vacuum lock between the tank and pump but the vacuum release line is new, there’s no vacuum sucking when removing the fuel cap, and the pumps pumping fuel freely.
After checking the plugs, they are clean with White tips which tells me it’s running lean. A few other signs of it being lean are running hot (gets to temp very quickly), and a smell from the exhaust which is not fuel.
ive fitted a larger main jet on the primary side (from 117 to 130) this has given a smoother acceleration but hasn’t seemed to improve the leanness.
Ive not changed anything else. The engine is high compression so sucks a fair bit of air in.
What can I do to increase the amount of fuel to run richer? Larger main again?

any help is grateful

[totalnova]

Take it to a carb specialist and have it set up properly on a rolling road.

[millworm]

+1 for rolling road, you'll be pissing in the wind without getting proper gear on it to see what shes doing

[leggattr]

This has been an obvious preferred choice but I’d hoped to make it drive somewhat further than it currently does so It would require trailering. Have looked locally but not had much luck finding somewhere.

[millworm]

Bit of a bop but spoken to atspeed racing?

[leggattr]

I’ve contacted 2 rolling roads within a 30min drive of mine, one doesn’t work with carbs but Track n Road in Essex does. They have quoted around £120 to set up. The only thing I need to think about is transporting the car their and back.

[leggattr]

This one didn’t come up in any searches so will contact them too.


Bit of a bop but spoken to atspeed racing?

[mowgli]

What dizzy & cam carrier are you using?