I building up my LO3. yeah i know, get a 350. well its a good 305 with very low miles on it. so i want to use it up. the whole bottom end was redone and it was bored .30 over so now i want to do the top. i was thinking about these heads with a LT4 cam with .494/.494 lift. Will this setup work? Will the compression be too high?

 

Ok i figured out the these have a 58cc chamber and will work on my 305. They already have 1.94/.150 valves in them. I was going to port them anyways to make sure i get good flow since the eastwood kit is only $30. Next i'm going to put a set of roller rockers on them. I'm thinking that i should upgrade the springs though. With 1.5 rockers ill get .494/.494 lift from the LT4 hot cam i want to put in this setup. Will Z-28 springs work for this or should i go with different springs?

 

Find you a set of ZZ4 heads, they have factory port work and better springs/retainers from the start. Good for .474/.510" lift out of the box. I wouldn't run the Hotcam personally. I'd suggest the ZZ4 cam or the GM 845 that is also known as the Crane 109821. They have very similar specifications and run very well in a 305 street driven application. This .040" over 305 with 059 305 Vortec heads, 10:1 compression, dual plane manifold with tweaked Q-Jet backed to a TH350 with 2,400 stall and 3.08 gears pulled around a heavy 1980 C10 long bed effortlessly.


I ran the very same cam, cylinder heads, and engine in my 5,300 lbs 1983 G20 van with a stock stalled 700r4 and 3.08 gears in the rear end. I had a TPI setup on it and doug thorley tri-Y headers. No shortage of getup and go in the heavy van. I didn't even really get on it hard until about 20-25 mph. In fact if you listen to the video you can tell my poorly "built" 700r4 was slipping badly on the 1-2 shift, so bad it hit the 6,200 rpm rev-limit in the TPI ecm several times. It was in Drive and upshifted 2-3 about 5,000 as well.

http://s243.beta.photobucket.com/use..._1468.mp4.html

This same motor is now in a 1980 Corvette wearing an edelbrock victor jr 4bbl intake, a Holley 650 vacuum secondary carb, stock exhaust manifolds backed to a 2spd powerglide with 2,800 stall converter and 3.73 gears. Still need to do a little tweaking on the car but it runs very well for being a small engine.

 

I decided to go with a L31 350 with vortec 906 heads, ported with 1.94/1.50 valves, 1.6 aluminum roller rocker arms, forged pushrods, comp cam's 280XFI HR13 that has a .576/5.70 lift with 230/236 durations at .050, Silv-O-Lite short skirt .30 over pistons for a compression ratio of 10:1, Cfm tech's throttle body, edelbrock performer tbi intake, a 2500 stall and 3.73 gears. The motors almost done and then I gotta word on the body since a bobcat ran out in front of me 3 years ago and she's been sitting in the garage since.