Guys,
I am in the market for header and exhaust. After looking at the Great Header test I was quite impressed to see the comptech header perform just as well if not better than the JDM 4-1 and DC JDM 4-1 header. But it still leaves questions in my mind as to why. The comptech quality is unquestionsed, they are buit very well. But why did it do so well in the test with smaller primaries and collector. How mant hp can this header take before it looses power? It seems to be cheaper to buy the DC JDM 4-1 but you still need to buy a new cat and /or test pipe. After this the price is the same! What are everyone's opinions? BTW, I was also looking into the comptech and Thermal RD exhausts.

 

my guess is if you eventually raise your compression ratio (ITR/CTR pistons) and get higher lift cams, the comptech header/exh would be less beneficial to your setup than SMSP, spoon, toda

 

Construction wise, I can vouch for the header. It is probably one of the best (if not THE best) 4-2-1 header on the market. The top end gains are not what a really good 4-1 can provide, but it is very competitive for the mid-range RPMs. Its pretty expensive at $500, but I found mine NEW for $320 on Ebay.

The collector is 2.25", looks way bigger than stock because the stock one has an inner tube that looks <2" in diameter.

I have never heard of anyone complaining about its quality, BUT many of the better 4-1's produce higher gains. If you're going mildly modded the mid-range gains of a 4-2-1 header may be what you would want and Comptech is a good choice. For pics, see my page.

 

At what point is it more beneficial to go to the 4-1 setup? I was thinking I would eventually putting in ITR cams

 

I disagree, the comptech header is not the best 4-2-1 you can get. There are tons that kick it's ***. It is one of the better ones with a 2.25" collector though.