170 vs. 225
Not trying to cause an argument Bill, but I've seen you pretty much echo my point about cubic inches not being really important with forced induction. Now of course when I make the point, I get disagreed with. That's cool. And typical. Mat, just disregard my opinion on this. I was trying to help, but obviously I went the wrong direction.
I probably over-stated the case for displacement advantages in this discussion about the `70/225 comparison, true. If you just want to make horsepower, you can spin a boosted 170 a lot faster than a 225 and probaBLY MAKE ABOUT AS MUCH TOTAL HORSEPOWER AS THE BIGGER MOTOR, BECAUSE THE 225 IS GOING TO THROW IN THE TOWEL AT ABOUT 5,500 RPM WHILE THE 170 WILL CONTINUE TO SEE HORSEPOWER CLIMB FAR BEYOND THAT DUE TO THE FACT THAt it has a MUCH shorter stroke AND the exact same cylinder head as the bigger motor. Sorry for the caps; I am a two-finger typist and have to watch the keyboard, not the monitor, and can accidentally hit the caps lock key and never know it....
Anyway, yes, the 170 is not that handicapped when it comes to making pure horsepower, but when driving around town, stoplight-to-stoplight (not racing,) the 225 will have a lot more off-idle torque to get the car rolling, and make daily-driving a much more enjoyable experience, I think. It's a driveability thing having to do with available non-boosted torque, but not total performance.
At the strip, there might not be that much difference, but the 170, in making those big numbers, would probably need to run somewhat more boost and wind up a lot tighter. WHICH IT COULD... just a different "build" in terms of valve train technology to accommodate all those r.p.m.s, which the 170 needs (and, is capable of, properly built) to achieve the horsepower numbers of a lower-revving 225.
I apologize, Rusty, for mis-stating my case; you were right all along...:oops:
