Quote:
Originally Posted by Slick
FWIW,
I had a totally stock, but well tuned 1970 Bonneville with the #15 head 455. 3.23 Safe-T-Track and turbo 400 (naturally), ~29" tall tires (P255/70R15 Radial T/As).
It was very fast for what it was. 13.90s at 97. My original 70 T/A RAIII, 3.31 Safe-T-Track, T400 ran 14.31 at 99.8. Runs at Capitol and Budds Creek.
Of course the T/A spun through all of first, the Bonneville was glued.
P cam in Bonneville (i.e. 067).
Bottom line: in mild form small valve heads can run!
Stuart
|
I totally agree with Stuart (Slick), Skip, and Cliff. These engines are sleepers and don't need large valves when the engine is fairly stock. Here is the dyno sheet of my '70 YH 455 360 hp stock rebuild motor with the original small valve #15 heads, a Summit 2802 cam and stock log manifolds. The compression was just a smidge under 10.0 to 1.
I believe it could have cracked 400 hp with more cam, but I was happy with the 390 hp/512 tq it made. I also believe it would have made 420 hp/525 tq with stock #64 large valve heads throughout the pull range.
Dennis