Roughly, how much would raising the compression from 9.5 to 10.0 on a cammed 5.3 be worth?

What is the optimal quench area and how does one determine it? How is it affected by mods such as porting and milling heads, or increasing or decreasing the thickness of the head gaskets?

Thanks guys.

 

Id go up at least a full point 10.5:1 Ive heard 1 pont in compression makes between 20-30 hp difference. Plus your exhaust will sound alot better

 

Half a point will be good for ~10hp across the board.

A tighter quench will help ward off detonation and give you a better squish area. A full point is going to be hard to pull off with only heads and gaskets and still have decent p2v for a decent size cam. I had my heads milled .040 and with a stock .054 gaphite gasket, mine was ~10.25:1. I was running a fairly small cam though (214/216 .535/.545).

 

So with the additonal chamber volume I'm getting from the porting, my heads are going to be milled .045. This will give me 10.0:1 with stock gaskets. If I went to .045 gaskets I'd get 10.2:1.

Problem is, cometics aren't made in a 5.3 bore size. They are 3.910" bore. Think that will be a probelm?

Think they'll fit with my cam?

 

I milled mine .050 and am using the stock gaskets with .566 lift, if I had to do it again I would have milled less and gone with a tighter quench.

 

That's exactly what I'm trying to do.

 

I really dont think you'll have any p/v clearance problems with 10.5:1 and a moderate cam with less than 230 duration and .58x lift, if you go with an aggressive cam I would clay the cc

 

The general concensus is that I'll be good, but I'll clay it and have a set of stock gaskets on hand just in case. I don't want to get into flycutting pistons at home.

 

U CAN ANGLE MILL THEM.ALSO MY 5.3 HEADS R SHAVED 30 AND R NOW ON MY 6.0 WORK GREAT.ALL YOU HAVE TO DO IS WHEN YOU SHAVE U'R HEADS IS SHIM UNDER THE ROCKER BAR THE SAME AMOUNT.

tighter quench.

NEVER HEAR OF THIS BUT YOU ALSO CAN GET THE CHAMBERS WELDED TO RAISE COMP.

 

What do you mean shim under the rocker bar? Why would I need to do that? Couldn't I just use a shorter pushrod like 7.35"