Performance Weber 40 IDA 3C
 

Hello.
I have a Weber 40 IDA 3C. I would like to improve their response and power but do not know what should I change jet and venturi.
Number- 70, 71, 72, 73, 73

http://forums.pelicanparts.com/uploa...1379448702.jpg

Thanks

What car? what engine build spec? What are your current jetting specs including idle jet, main jet, Air correctors, emulsion tubes, venturies?

If the car is jetted properly and you have good AFR there is not much you can improve. What exactly do you want to do? Your comment about response and power is vague at best. Properly setup webers have fantastic throttle response and make very good power.

Timing could be the issue since Webers have no place to connect vacuum lines for the advance/retard on the distributor.

This a VERY open-ended question. To do it right you need to have at very least an air/fuel ratio meter (one you can drive down the road with) or a chassis dyno. Then a lot of parts to play with.

I sit it do not have idea great on this topic and not wise that to put.
Car: Renault Alpine A310 V6
Motive: V6 PRV
idle jet: 55
main jet: 125
Air correctors: 180
emulsion tubes: F26
venturies: 30

Thank

The A310 is similar in displacement with a carburetor equipped 2.7 in the 911s. The engine probably has power output similar to the 2.7 since the V6 A310 was capable of 140MPH (230KPH) performance. Assuming this is true then jetting for this engine would look like this:

• 34mm main venturis
• 145 mains
• F3 emulsion tubes
• 180 air correction jets
• 60 idle jets

Performance testing would be necessary to confirm jetting sizes but the 34mm venturis and the F3 emulsion tubes will work for all jetting combinations. If a little less top end power is desired then 32mm venturis and 135 mains would be the choice to start with.

Thank you very much for the reply. The truth that what I expected and needed.