i can buy a set of 799 heads right now for 200 bucks are they worth the money? what kind of performance gains can be seen on a 01 5.3 with full bolt ls6 cam.

 

need to know asap

 

there good if you mill them a lil 243/799 is the same head

 

i thought 799 was a milled 243. how much would be expected just bolting them on and if none how much would they need to be milled

 

Unless you have them cut to get back the compression you would otherwise lose by just bolting them, any gains from the slightly better intake and exhaust ports and larger intake valves would be offset. On the other hand, if you had them cut about 0.025” to bring the combustion chambers back to the size of your current heads you should net a reasonable gain.

Remember, the 5.3L engines these heads were installed on also came equipped with flat-top pistons vs the dished pistons your engine currently has.

 

5.3 head is 61.15cc 243/799 is 64.45cc

 

Yessir, there's the rub...good ports but bigger combustion chambers. If it were me I'd get them and spend a few bucks to have them milled .025-.030. A reputable machine shop shouldn't charge much just to put them on the lathe and take a little off

 

let me know if you dont buy them i want them yeah for the future lol

 

200 is a cheap price get em

 

I want to watch somebody mill heads with a lathe