On a stock 350 block will the stock pistons and crank reliably hold a compression ratio of 9:1 or more? If not what piston config. should I go with to get the best reliability? Thanks

 

Easily. Stock compression for the 87-89 L98's is 9.3:1. It goes up to about 9.7:1 for the 90-92 L98's due to the change to flat top pistons.

 

Stock internals will handle about anything except NOS and +6000 rpm. If in good condition to start with you should have no problems with up to 10:1 CR with good fuel.

 

even alot of 305 engines were more than 9.0 CR

9.0 is nothin

even 9.5

nothing crazy at all


why were you thinking it might be bad ?



good luck

 

Keeping longevity and performance balanced. What would be the best compression ratio to go with then?

 

The correct one to match your cam specs, cylinder design and material, vehicle usage, etc, etc.
It's not like I can say, 9.5:1 is good for you, since I have no idea what else is in the motor.

 

Well I have a brand new 350 short block from GMPP stock bore, stock stroke, etc. I have Edelbrock Performer RPM Intake, Edelbrock Aluminum Performer RPM Cylinder Heads (64cc), Edelbrock Hydraulic Flat Tappet Cam, Summit Aluminum Roller Rockers (1.5), and thats basically all I have right now.

 

11:1 is what I ran on my Dart Iron Eagle 180 headed, production LT4 cammed 355 TBI. Keep the engine properly timed, run a good quality fuel, proper mixture, and the proper .040" quench, 93 octane, 32* total advance and ZERO detonation.

 

I wouldn't go lower than 10.5:1.

 

My motor is going to be carbureted is that going to make a difference as to what compression ratio to use?