Cascade Crew

QwkTrip · Posted: Wed Apr 11, 2007 6:52 am Post subject: Izcain - down in the 10's !!!

Izcain, I see in your sig that you broke 10's in the quarter. Congratulations!!! Cool

That's a small club and we appreciate your expertice on this board. I wanted to follow up and figure out if that was just the result of a cam swap of if you did other things too. You really blew past your old time! Thumbs up

Also, I want to pick your brain about my big block. Ya, the supercharger looks cool but it's really too small for a heavy breathing big block and doesn't fit under my hood. I've given some thought to selling my supercharger and oval port heads and pooling that money for some nicer heads and a lower induction system easier to package under the hood. I'm not sure which heads I have now and can't get the casting numbers until I pick up the car in July. But they are likely a typical '70s oval port with a mild amount of porting work on the exhaust. I know the engine was built with TRW flat top pistons I was told it is about 9:1 compression as it stands today. Do you think it would be possible to break 10's with an oval port head and pump gas or do I have to change to rectangular port? It seems that rectangular port heads require a different piston to keep compression in check. I know very little about big blocks and what works for them. All my experience is with small blocks.

chevymad · Posted: Wed Apr 11, 2007 5:27 pm Post subject:

If you go to the team chevelle website there are many chevelles in the 10s running oval port heads. Huge debate but most consider the large ovals better then the factory rectangular heads now. The number you want seems to be the mid 70s 781 casting. Though there are other good ones as well. There are some aftermarket ovals now that are really flowing too.

No idea on power or time but the 454 I built for my truck is a 73 with domed pistons and 781 heads. Only have the small valves though. Running 60204 lunati voodoo cam, performer rpm, holley carb, long tubes, aluminum roller rockers etc.. 10:1 compression. Really sounds sweet and tachs up fast. Factory flat tops and the 781 heads come in at a ridiculous 7.9:1 compression.

QwkTrip · Posted: Thu Apr 12, 2007 12:45 pm Post subject:

I do have good size valves. I know I don't have the 'peanut' chamber heads. I think the combination I have now will work well together. But I don't think my heads are good enough for a strong naturally aspirated engine. My engine originally ran naturally aspirated in a Chevy crew cab show truck. It moved the weight of that crew cab pretty well. I swapped out the cam, upgraded the valve train, and added the supercharger. Basically prepped it for another 100+ hp.

I will check out Team Chevelle. I've been home all week on pain killers so I'm bored as hell anyway. That's why you've seen more posts from me during the day. Wink

Dewey316 · Posted: Thu Apr 12, 2007 12:49 pm Post subject:

That explains a lot. Hope you get to feeling better.

Team Chevelle is a great site, tons of good info.

I'll add that I don't know a darn about big-blocks, but give me some numbers and I'll do math. Very Happy

QwkTrip · Posted: Thu Apr 12, 2007 12:50 pm Post subject:

You have an engine simulation program?

Dewey316 · Posted: Thu Apr 12, 2007 1:01 pm Post subject:

I don't, but I sure bet I could find one.