Lee, Edited 7/18 for factual accuracy! S
Regarding pistons in 302s. They were the same for 2V or 4V engines.
(FYI- it is in 1969 in the 351W engines where dished pistons were used in 2V engines vs flat tops for 4V engines!)
The 302 head castings are clearly marked 2V or 4V inside the valve cover area between valve springs, however the valve springs, valve size, camshafts are SHARED 2V and 4V!!!! Surprised me!!!
The 2V and the 4V were otherwise essentially the same engine, but for the intake manifold and perhaps the curve on the distributor! The 4V carb offers a few CFM more than the two barrel version, but the choked down exhaust passages and manifolds continue to be the same..... Only the dual exhaust varies from single. Questionable how much flow the extra pipe really offers......vs the single larger pipe.....in the end!
I think SGC's statement was.....understated. What does a bunch of kids with pencils know....? I don't think they ever figured out a proper "third" write up of this project..... They threw a lot of parts at the car.....but I wonder about the thought process and subsequent execution.
I need to dig out my copies of this writeup and refresh the grey matter!
There is a LOT more potential out of a stocker 68 302! The intake ports are huge and you have a 10.5:1-ish compression ratio with essentially closed chamber heads. The ONLY things holding it back are the puny exhaust ports, which Shelby(?) fixed with the specially ported GT40 heads that were used for LeMans etc, and the dismal low lift camshaft!
Port the exhaust side of the heads mildly, (get rid of the air injection "bump") and put in a HiPo 289 grind cam or bigger, and you have a better breathing small block to play with up to at least the 6000 level RPM's!
Toss in some forged pistons and better rod bolts with that bigger camshaft, and you are rolling now! 400HP is easy. (300 at the rear wheel!)
Ciao!
Steve