i can get my hands on a set of ls1 heads for around 100 dollars and i planned on porting them a little and having them milled. how much would i have to mill off of the heads to get the cr to 9.8 or 10.0? also do the ls1 heads flow more than 5.3 heads from the factory?

 

don't waste your time or $


use the search feature!

 

ported heads arnt worth my time or money? if i had access to 5.3 heads for that price ide use them. but these are ls1 heads and i will do the porting myself and i will mill them in my uncles machine shop.

 

Their are a few different castings on the ls1 heads and the compression can be different on different on the castings. What is the casting number on them. If you have to mill them alot you will need to check for valve clearance and maybe fly cut the pistons.

 

why not just port/work your own heads?

 

I asked this question last night but mine are already PnP'd.

https://www.performancetrucks.net/fo...54#post4610354

 

the downtime is what i have to cut down on. this is a work truck and my trans am wont pull a trailer haha. but i could get away with not having it for 2 days tops and that just wont give me enough time to port the heads too. it would just be alot easier to use the ls1 heads. i need to call and ask what the casting numbr is on them.

 

You should be able to pick up 4.8/5.3 (862) heads for ~$100 that would be better start with because of the smaller combustion chambers.

You'd have to mill quite a bit off the 241 heads to keep the compression ratio intact.