l31 build help
l31 build help i have a l31 with .010 ground off the crank speedpro forged pistons. .010,3angle valve job on the heads stock roller lifters comp xe270 cam petronix hei distributor and a holly 670 and 750 carb. tried both carbs and car still dosent have any power. i have the motor in a 1983 chevy caprice. is this a good cam for such a heavy car? i also have a built 700r4 with a 2500 stall in it. and headers.
L31 is a vortec 350 right? If so, that cam should work great with those vortec heads, might need to try the timing if it is not running good because that cam will make lots of torque to get even the heaviest of cars rolling.
Teching In
Joined: Oct 2007
Posts: 34
Likes: 0
From: Mount Airy, MD
you need to address the valvesprings and pushrods if you already haven't. Use oe lt1 spring keepers and retainers, and get the howards 98213 springs from sumit. pick up a set of Comps hardened 5/16 pushrods, mix, repeat, etc......
Launching!
Joined: Oct 2006
Posts: 289
Likes: 0
I agree with ZONES...what's the timing look like? I'm guessing the compression is around 9.5:1. With that low compression and that cam, you will want around 12 degrees initial, 34 degrees max (all in by 3000 RPM) and also a vacuum advance hooked up. I had similar issues on the first engine I built. I had the timing set per the factory (6 degrees initial). The car was a turd. An old timer at the track set me straight!
