I am about to order some pistons for my stage project, what compression is the best to choose, I don;t really think I;ll be going over 30 psi boost though on c-16 maybe 23 psi on alky and 93. looking at a 230 cam about or so in size.
How much over 30 psi?
Sounds reasonable, Bison posted that ( you) Allan should be running 10.25, or your combo will need 40 psi boost to make best results, do you think this is safe?
How much difference is there between 8 and 9?
That could of been due to the camshaft you were using, too.Not sure what answer your looking for but when I went from 8:1 to 9:1 I went considerably faster with lower boost.
Allan G.
A couple interesting stories. When I was running 11.25 with the second motor, I had set a boost limit of 22 psi. The engine did good with the high static CR and the 22 psi boost. First time out on a 1/4 mile track, low nines. On the last launch of the night the boost spiked to over 22 psi and a rod folded due to a lean condition which, with the rest of the combination of high static CR and over boost, set off preignition. The front of the car rose, and then pop!
The next motor had 9.25. The boost limit for this engine was set at 40-45. On a 1/4 mile run, the car performed an 8.70s pass with about 30 psi boost. The most interesting thing about this run was that a dangerously lean condition had developed for most of the pass. So lean that the engine was lean surging across the finish line. But, the engine suffered zero damage. The engine survived to make another pass, after fixing the lean condition.
How much difference is there between 8 and 9?
Alky V6 said:This is a street application, correct? Is it really worth it to push things to the edge for a street car where maybe an extra psi of boost would make up the difference anyway?
I vote for keeping it on the safe side, and not trying to push it out to the edge. Who knows what street gas is going to be like when Obama gets done with us.