I'm putting together a budget 350 for a buddy of mine to go in his 63 nova. I was wondering what you think of this combo and will it work? Its going to be a rebuilt stock short block, std bore, with a set of the common Speed Pro 345NP pistons. I'll be using the Clevite version. This is a 4 valve relief flattop piston. I have a Comp Cams High Energy 268H cam for it. Which is a .454 lift and 218 duration cam ground on a 110 lobe seperation. Now for the heads, we have a set of 14014416's, which are a 305HO head. They have the 58CC chambers which would make for good compression. The heads already have nice Manley style 1.84 and 1.50 valves. However, the heads dont flow the greatest. They flow 195CFM at .500 lift on the intake and 110CFM at .500 lift on the exhaust. They might flow slightly more with these better valves. But I have read post on a third gen camaro website of guys making these flow as well as old double hump fuelie heads if not better. Where going to run a performer intake with a 600CFM carb. Because its going in a 63 nova, he's going to use a 1 1/2 primary tube header. Do you think this combo will work to make 300 HP? Are these heads not gonna cut it? By Bringing the compresion way up with these heads, will the mild performace parts (small cam, low flowing heads) work?

Originally posted by Stroked66:
I'm putting together a budget 350 for a buddy of mine to go in his 63 nova. I was wondering what you think of this combo and will it work? Its going to be a rebuilt stock short block, std bore, with a set of the common Speed Pro 345NP pistons. I'll be using the Clevite version. This is a 4 valve relief flattop piston. I have a Comp Cams High Energy 268H cam for it. Which is a .454 lift and 218 duration cam ground on a 110 lobe seperation. Now for the heads, we have a set of 14014416's, which are a 305HO head. They have the 58CC chambers which would make for good compression. The heads already have nice Manley style 1.84 and 1.50 valves. However, the heads dont flow the greatest. They flow 195CFM at .500 lift on the intake and 110CFM at .500 lift on the exhaust. They might flow slightly more with these better valves. But I have read post on a third gen camaro website of guys making these flow as well as old double hump fuelie heads if not better. Where going to run a performer intake with a 600CFM carb. Because its going in a 63 nova, he's going to use a 1 1/2 primary tube header. Do you think this combo will work to make 300 HP? Are these heads not gonna cut it? By Bringing the compresion way up with these heads, will the mild performace parts (small cam, low flowing heads) work? You definately gotta get some better heads IMHO. It'll be worth every cent down the road, wether you're going with a performance motor or an everday grocery getter. As for everything else, it sounds like it'll work. I believe you could easily accomplish your goal of 300hp, maybe even a lil more with the right heads, exhaust system, and ignition system. Good luck! graemlins/thumbsup.gif

I'm afraid it will probably ping itself to death. A buddy built a nearly identical engine for his 3.73 geared '70 pickup...the only difference was a 214/224@.050 cam on a 112 lsa. It made 180psi cranking compression with those same pistons and heads, and pinged on anything less than 93 octane fuel and the timing retarded slightly. It ran pretty good though...easily a 300+ hp motor. With the 268H I think you'll be running 180-190 psi. With those heads, I would step the cam up just a bit to knock off some of the cranking compression. Maybe something like a 270 magnum, or XE274.

With all the different compression ratio calculators on the web, I have found that most of them say it'll be around 9.9 to 10:1 compression. I dont beleive thats bad at all. IF I polish the chambers on the heads and retard the timing a little, I think it'll be fine on 93 octane. Will see