I have heard of guys doing .30 to .35 on a stock 5.3 with 862 heads.

Here's what we're working with.
2005 crew cab z71 on 35" tires. Gunna build tranny and do gears. Doesn't wanna do a camshaft. So what is the max we can mill these heads to run on 93 octane gas? Also we are going to port and polish them. And what is the best factory spring we can put in them? Yellow? Blue?

I saw a truck in person that the heads were milled and unknown how much on 35's blowing the tires off better than my h/c/I single cab. So I know it helps.

 

Every 0.007" off lowers the volume 1cc. Stock is around 62cc. Bumping it to 59cc would give you about a 10to1 compression.

Max i would say is around 0.030" before ypu get in to intake not fitting well.

 

My prc 5.3 heads are 706 heads with a 58cc. Not sure how much that equals compared to milling but I am sure texas speed would give you the answer. I know if you go to much you will have problems with your brackets and intake manifold lining up. I was fine.

 

my 243 are milled 0.040 an intake fits just fine. was gonna do .045 but i bought these heads milled already.

also .006 is 1cc

 

If you milled them to be 57 CC you would be dang close around 9.99:1

The factory combustion chambers very a little bit, but there usually in the 61CC range to start with.

Yellow springs were discontinued and were replaced by Blue springs.

 

all my calculations would put 57cc chambers at around 10.2:1 with a stock .051" gasket.

59cc is where 9.99:1 is with a stock .051" gasket

 

I do em 30 to 40 and get a shorter pushrod. Should wake the engine up nicely from the higher compression.

 

So so if I cut my 706 heads 40 it makes them into 57cc? At10.2.1
And and if so do you have any idea what running the thinner head gaskets would bring it up to they are 40 I just spent $200 on them so I really want to use them if possible lol

 

I'm I'm really not sure how this app work so I don't know if it's actually working or not I'm new to it but I think I'm going to cut them 40 and use my thinner head gases which are 40 and shorten my pushrods to match and run LS7 lifters with a stage 3 low lift cam Texas speed that's what I would like to do if possible I have not check valve clearance yet still waiting on cam to come just wanting to know how much I could cut them before I ran into intake problems or any other problem

 

I'm I'm really not sure how this app work so I don't know if it's actually working or not I'm new to it but I think I'm going to cut them 40 and use my thinner head gases which are 40 and shorten my pushrods to match and run LS7 lifters with a stage 3 low lift cam Texas speed that's what I would like to do if possible I have not check valve clearance yet still waiting on cam to come just wanting to know how much I could cut them before I ran into intake problems or any other problem