A friend of mine bought a used ls6 motor and already has a set a patriot ls6 heads and wants to sell me the stock ls6 heads for pretty cheap. what would happen if i just added some 1.8 roller rockers and bolted the heads up to my 98 ls1? stock cam and stock internals. would it even be worth pulling the heads? would i need a tune? and lastly how bad would my mpg suffer? thanks guys.

 

Im not an expert but i think they might flow a bit better i dont really know much about to rockers but over stock i think they would be better but dont quote me on it

 

Well the LS6 heads flow quite a bit better then yours and the 1.8 rockers will be like adding lift to your cam so even though your stock cam while larger then the 01-02 cams is still smaller then the LS6 camshaft so with the rockers and an LS6 intake you should be about the same HP as a stock LS6 plus any bolt ons you have. I would would expect around 40-50 hp for just the heads and rockers.

 

Wow thats pretty good. would i need a tune?

 

you probably won't "need" a tune, but it would help. However you will need new springs with the 1.8 rockers, unless the LS6 heads also have the LS6 springs. I would not use a stock LS1 spring with 1.8 rockers even on a stock cam, but that is just my opinion.

 

if i did get the heads they would probably be fully assembled, including ls6 springs . thanks for all the help, also how hard would it be to pull the heads?