I want to change my header to increase my horsepower. I have an ls. Now an ls has better mid-range then a gsr but has lower high end power. My goal is to build off the b18b's low mid range power. What header would you guys recomend. I'm looking for the stock look so looking more at type-r header beacause of its larger collector of 2.5". Now there is the famous spec 98 ITR header thats a 4-1 header. In my mind it should create more high end power but comprimise the mid-range power. I have heard that the 96 spec ITR header is 4-2-1 and also has a collector size of 2.5" . Im thinking this would probably would be better on the ls motor beacause even if the older header is not as good high end, the b18b does not rev high enough to use the full benifits of the 98 spec header. I have not found much information on the spec 96 itr header. I was hoping you guys would help me out with some insight. Thanks!

 

The 96 manifold is simply a cast manifold with tubular secondaries running to a larger collector than you have stock....that's it. It's basically your stock manifold with a bigger collector.

The 98 manifold is the one piece mild steel tubular manifold with horrifying ground clearance and a good (but certainly not great) collector. It won't compromise your midrange at all, not compared to the stock LS manifold anyway.

Personally I wouldn't be looking at either of them. There's a Toda replica available now, and the price isn't bad. If not that, the Hytech replicas have been steadily dropping in price.

Have you made arrangements for a larger cat/testpipe to accommodate the larger collector? And what are you doing for the exhaust?

 

I was thinking a type-r exhaust of 2.25" diametre. What would be the best combo with that. So your sugesting a replica of somesort? I just dont know what cat to get if I get a longer header? what do you sugest? thanks for the info.

 

Any decent Muffler shop should be able to make it all go together pretty good. But I would recommend stepping up to a 2.5" cat and exhaust. Also the Toda replica is stock length.