77TA

How much compression are you guys running on your stock 5.3 before you boost them? The reason I'm asking is because if I go with the stock heads for my 5.3 I will be running 9.9:1. Just trying figure out how much compression is to much. I was just wondering about pump gas and detention problems with that high compression.

NoGo

iTrader: (2)

Depends on how much boost you are going to be running, how well your setup intercools, what octane gas, and backpressure if you are running a turbo.

If it was my setup at 9.9:1, I would try and keep it around 12-14 lbs on 93 octane. Closer to 14 with a supercharger and closer to 12 with a turbo. Just my 0.02.

If you are running stock pistons, I would try and limit the power to no more than 550ish at the tire.

Many other folks on here push the envelope more than I do.

alexcoreas

iTrader: (1)

What year is you 5.3 BC if your at 9.9:1 you have an aluminum block. Only two cast iron block had 9.9:1 the LY5 AND LMG

77TA

It is an 08 aluminum block. Thanks for the info too.