Hi again.Just an update on the car holding back at 2750 revs.I found whilst driving the car that if you pump the throttle pedal the revs will build up again and rev upto 6k but if you just stamp the pedal it just hlods back.Having not built the car fully was unaware of a "petrol king fuel saver/regulator"which is suppose to aid the fuel supply at tick over to stop over fueling from the twin 45s and expand and allow more fuel through under acceleration.Has anyone come across these and are they really required.The engine is a 2.1 pinto with twin weber 45s.thanks guys.

Needles too small??
Fuel pump not man enough?
Fuel filter blocked?


Sounds like a vacuum or fuel problem. Maybe even timing?

ive not come across that one but a regulator must be fitted if your fuel pump can supply over 3psi, i had a problem that my fuel pump deliveres 4.2psi and this caused my carbs to wee fuel and be super rich on tickover and poor out the trumpets into the filter

thanks will try and test pressure tomorrow.cheers

If you are getting revs after pumping the throttle it means that the carbs accelerator pump is delivering the extra fuel the carbs need.
If you have a petrol saver regulator these usualy have a vacuum feed to the top thus changing the fuel presure as the vacuum changes, not advisable with Webbers, you should have a Malpassi Filter King which will only set the base pressure.

Pumping the accelerator with DCOE's squirts fuel into the engine.

Hints that one way or another you arent getting enough fuel. Could be a fuel delivery issue, but as you are pumping and getting fuel thrown in then I would suggest the float bowls are full.

Its more likely to be that you need bigger main jets (I was running 140s on my pinto)

David