nuttkaze

To make a long story short I called summit to see what they had to boost my compression up in my original 4 barrel 71' cutlass witha 350.

I told him I'm going with:

Clean up heads and go with 2.00 intake valves
Headman Headers
Eaton Posi w/3.36 gears
Rebuild my Quad Jet Carb
Edelbrock 7111 Intake
442 Air cleaner
MSD Ignition
I will choose cam after I know my compression, but I'm shooting for 9.5

He recommend TRW Speedpro Forged Dish Pistons then my phone disconnected and when I called back they were close...that was last night.

I wondering why he didn't recommend the TRW Speedpro Forged Flat Top
http://www.summitracing.com/parts/TRW-WL2320F/

What will be my compression if I went with the dish pistons vs. the flat top pistons?

cutlassefi

Can't really answer that, need to know head cc, deck height etc. but typically the flat top will give you about a half point or better over the regular dish.

joe_padavano

X2, it depends on actual measurements, but as a ballpark assessment, the 68-70 W-30 motors with steel shim head gaskets and 64-ish CC chambers were factory rated at 10.5:1. Of course, production tolerances can change that, and using the thicker FelPro blue head gaskets will lower it.

svnt442

Joe did you mean W31?

joe_padavano

Yeah, sorry. I'm kinda big-block-centric...

Warhead

Too bad these heads came with a 68-70cc chamber from the factory.
Factory rating, and production pieces, are sometimes two different monsters.
It will take at least a .030" cut to get to the 64-65cc chambers. Then cut another .020" to account for the gaskets.
Then you might be at the 10.5:1.
If you skip the milling, you will be much closer to your target, IMHO.
Jim