5.3 heads

[dpeach]

I am able to pick up some 5.3 heads for pretty cheap. These heads will help raise the CR right? how do they flow compared to stock? I was looking for info but had a hard time doing so. Would i be better off getting my stock heads done? or is it not that big of a difference. Should i save up and get a cam instead? Thanks for any information.

[bills98ta]

You will have to port them greatly & have larger valves installed. Then, you will have a great set of race heads. With the stock flat top pistons, you will be around 11.5:1 CR...
That's what I'm using, but I have lunati +12cc dome pistons & have 14:1 CR !!!
You can have the stock seats opened up to accept 2.02 / 1.6 valves !!!

[dpeach]

is it worth it to get that done to the 5.3 or is it better to have it done to the 5.7. or try finding ls6 heads? just curious for the cheapest way until i can afford some quality heads, or if its even worth it.

[bills98ta]

is it worth it to get that done to the 5.3 or is it better to have it done to the 5.7. or try finding ls6 heads? just curious for the cheapest way until i can afford some quality heads, or if its even worth it.

I consider my 5.3 heads right up there with AFR heads... The LS6 heads will give you 11:1 CR without all the extra work... But, you can get the 5.3 heads for under a 100 bucks ussally. It is a little work to build the 5.3's, but if you have resorces to get the machining done they're worth it, if not, I'd go with the LS6 heads. I'd guess I have around 500.00 in mine, including the cost of the valves, but I did my own porting...

[ls1camino]

I used Ported, Polished and Milled 5.3L Heads for my H/C/I swap. The previous owner of them had them CNC Ported, 2.02/1.60 Valves put in, and milled to 59cc Combustion Chamber. I am pushing 12:1 compression ratio with a .040 MLS Head Gasket.