what are the measurements of the stock Ls1 headers? I am looking into getting something a little more beefy, but first I want to know what the original size is. Any suggestions on better headers (their measurements, if you know them) possibly long tube headers too? thanks

 

Actually, from what I've heard, the stock LS1 exhaust manifolds (they arent headers) make more power than most sets of headers will.

 

The stockers have 1.5" primaries with either 2.25 or 2.5 inch collectors. Shorty headers are a waste on an LS1 since they typically only add 5 to 10hp. The stockers are basically perform as a shorty header from the factory. Long tubes really wake those motors up and most see gains in excess of 25hp.

 

Sounds good, I am looking at getting some with 1.75" primaries and 3" collectors. I wanted to see what the difference was. Thanks for the info, does anyone have any better suggestions?

 

I would look into some 1 3/4 long tubes if this is going on a stock motor. The bad part is that they have to be custom made to fit into your 3rd gen.

 

And the cost of LS1 headers is just rediculous, compared to a set for a regular SBC or LTX motor.