I have an HO car I've owned for 33 years. I modified it 25 years ago before I even give a damn about the internet and what was out there. I know there is a taboo / stigma attached to cutting the round port heads, but I done it anyway. If you want it too absolutely romp and dont want to deflower your 7F6 heads, you can go this route...
Buy a set of Edelbrock Performer aluminum RA IV heads from Butler. They can machine them to any level of performance you are looking to have. Tell them what you want and they will give you a price. There are several other guys who do head work on here that are just as capable as Butler. So just do your homework and slap an 041 cam in that jessie...you'll love it. You'll also have to fatten up the carb a bit also. If yours is a matching number HO carb, and you don't want to modify it either...contact Cliff Ruggles and tell him what you are building and he can make you a carb that will match your build.
I brought my compression up by replacing my pistons with +0.030" TRW flat tops and angle cutting the heads down to 105CC. The TRW's set higher (taller) in the hole than the stock Pontiac's and give you a virtual "0" deck height without decking the block. My 191 heads were mildly ported, back cut and given a 3 angle valve job. I took it from 8.4 to 9.2. The RA IV cam would work a lot better with CR at 10:5 or even higher. You can do that with no problem with an aluminum head motor and suffer no detonation problems. The RA IV has 87 degrees of overlap built in it, the higher the compression, the better.
One guy said with no engine mods done...you will experience a little sluggishness in the lower rpm range, he's right, you will, for about 1 second when you kick it. If your already in the 2500 rpm range, you'll never know it.
If they would have had the Edelbrocks 25 years ago, I would have been on them with both feet.
All the stuff you asked is purely left to guess work now days. There isn't high octane pump gas. Except for racing fuel (5-6 bucks a gallon) so there is no way to answer you. Don't be afraid to go with a RA IV cam though. Pontiac would have stuffed them in all of their round port motors if it hadn't been for the damn dawning of the Ralph Nader era & the fledgling EPA polution police.
my $0.02
|