what should be the exact mm of the carb spring i cut three coils of and drilled to holes 1/8
But is there a exact mesur for the spring thanx???

 

might want to call mr hp on cutting that i've seen guys do that and i didn't see any difference.

 

The factory seems to have used two different spring lengths.

Be carefull and do not go shorter than 3 inches.
Total active length is 2 7/8. If you go shorter than this your slide will be bouncing and running very rich at slow speed.

I agree that performance varies. Best performance seems to be only when you run a direct carb-mount filter or lid-on uses. Running lid-off appears minimul.

I am getting ready to test 3 proto springs that I hope to match direct,lid or lidless.
Weather has prevented me from testing.

 

I do not know what the dyno results would be, but I drag raced several times with the lid on and off. I could not tell a difference. I did notice at a idle I have better throttle responce when snaping the throttle with the lid on. lid off, it seems to choke a little before catching up. sometimes it even died. I think I will leave the lid on unless somebody has dyno results to prove otherwise.

 

i think there is some dyno results out that show leaving it on is better, now if i could find that little black plug, and the drain cover[img]i/expressions/face-icon-small-smile.gif[/img]

 

Direct mount will generate the most peak horsepower.
However, running with the lid generates the most torque and widest horsepower band.
That is why I am testing new springs to have the best of both torque and hp.