First, the transmissions. I have a hunch that the Customline is a three on the tree, and I was wondering whats the deal with the overdrive transmission. Is it two speeds plus overdrive, or is it three plus overdrive, and what is the overdrive ratio.

Anyway, I would stick a nicely sized cam in the 272 or 292 to get that nice sound and some extra performance, as well as my own, custom exhaust (exiting right before the back tires), slap on some cheater slicks and get a nice '50s hot rod look going. I would plan to get a 352 or 390 in there soon (dont hate me, FEs arent cheap either but Y blocks are just too darn expensive fo the performance I want, I NEED DISPLACEMENT!!!!!) For the mean time, do you think I could manage to get 15s iout of the 272, if thats what it is? Depending on what the overdrive ratio is I would slide a 9 inch under it, with at least 3.91s. Maybe more. A Holley 600, maybe headers if I could get a piar cheap enough. Also, here comes another 272/292 question, did they come with forged pistons? I dont think they did, but I would probably have the heads milled too, to acheive at least 10.5:1. Ive heard some stuff about cast pistons with high compression, and my general understanding is that 10-11:1 is as high as they should be taken. Is this true? because for 70 cents more a gallon than what I have to pay for 93 I can get aviation fuel from our local, small airport. If I can get sky high with the compression, I'll get it thumping right up there as high as possible without running into valve clearance issues, I think 12.5:1 compression might make for a pretty nasty running little 272 or 292.

Im the type of guy who likes to tinker with stuff, and I would definately spend some time with this car at the strip. Do you think I can get into  he mid 15s (with 10.5:1 compression) and if I can go higher witht he compression, how quick do you think I can get? Im willing to pin the needle to somewhere in the 6 grand to 6500 range if theyre forged. Dont want to push the stock shortblock too much though. Could a high 14 be possible with some skull cracking compression? And how high do you think I could even get compression wise before the were valve clearance issues, figure about .450 lift.

OMG THOSE PORTS ARE HORIZONTAL!

The overdrive trans is a 3 speed plus overdrive.  The ratio is .67 to .72 depending on which one you have.  You cannot mill Y heads enough to get 12.5 compression, you would have to use pop up pistons.  The stock pistons are cast.

John

John - "The Hoosier Hurricane"

I grew up around several Y's in the early days that were breaking into the thirteens with just gearing and moderate compression ratio increases through milled heads and port work.  There were a couple of cars that could break into the twelves while still being Saturday night drivers and these gave the Chevy guys fits to say the least.  As Hoosier mentioned, popup pistons will be required for most compression ratio increases over 10½:1.  Increasing the compression ratio is definitely the easiest way to get the power level up but with that needs to be some corresponding changes to the camshaft and head flows to capitalize on this.  Just keep in mind that with any power increases, the bottom end parts need to be sufficiently upgraded to defray any premature parts failures.

Lorena, Texas  (South of Waco)