Author Topic: Powerpiston spring  (Read 3701 times)

Offline Marx3

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Powerpiston spring
« on: January 09, 2010, 01:33:35 PM »
hi, rebuilding a carb for a 383 street-engine. Cam is 268 adv- duration, I figure it will produce about 12-14 Hg in idle, closer to 15 than 10 I hope, but what color spring should I start out with? Are there any specs for the colors anywhere?

Offline Cliff Ruggles

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Re: Powerpiston spring
« Reply #1 on: January 09, 2010, 02:40:03 PM »
Any of them would work with that much vacuum at idle.  I'd start out with the light blue spring, it's our own general purpose high performance spring for moderate size cams.

The orange spring is the lightest, for big cams and low vacuum at idle.  The long green and dark blue are for smaller cams and high vacuum set-ups....Cliff

Offline Marx3

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Re: Powerpiston spring
« Reply #2 on: January 10, 2010, 01:25:52 AM »
Okay great!!! Good to know about the colors! thanks!