ITRCA

What do you think is better. I have heard that the JDM losses alittle down low but gains at the top and that the DC has no loss down low and gains from 4000 up to redline???? What one should I use?? If I use the JDM do I just need the gasket with my stock cat or do I also need the flange?? Thanks!

The JDM DC 4-1 and the 98 Spec JDM 4-1 are virtually identical, the DC piece is basically a copy. The nice thing about the OEM header, is that you can add the heat shields, other than that, I'd probably, just on price and weight, go with the DC piece. But either way, you're gonna need the flange, the collector end of both are a 2.5 inch diameter, so you'll also need a special donut gasket, sometimes included.

Later,
Aj

You shouldn't lose any power on the low end. My pre and post-header (ITR JDM 4-1) dyno plots look identical until 4000 rpms where the header starts to make more power over the stock unit. I gained 10whp and 6wtq from the header and mild VAFC tuning. I'd post my dyno plot, but my web space is having issues at the moment.

Thanks for the input. I will go with the JDM for sure.

Aj wrote:The JDM DC 4-1 and the 98 Spec JDM 4-1 are virtually identical, the DC piece is basically a copy. The nice thing about the OEM header, is that you can add the heat shields, other than that, I'd probably, just on price and weight, go with the DC piece. But either way, you're gonna need the flange, the collector end of both are a 2.5 inch diameter, so you'll also need a special donut gasket, sometimes included.

Later,
Aj

TO add to that DC has the lower setion of the primaries designed a little differently and the one problem I would see if gound clearence. Beyond that they make close to the exact same power and the DC is slightly lighter with even the OEM JDM piece being 9 lbs lighter than stock.

Actually, the power gains in the DC sports JDM header are much more significant than the stock JDM header. If you want to see a really impressive header comparison test, with dyno charts I would go over to superhonda.com and go to the discussion board in the Type R area. It's a sticky post that has many headers tested. The only headers that produce more hp and torque on a dyno than the DC sports JDM headers are the Spoon, Mugen, and SMSP headers...all of which cost over $700. They averaged just about 19 hp to the wheels, and the DC sports averaged about 17 hp. I would recommend the DC sports JDM header as I have been very happy with it's performance, but I would also recommend getting a Carsound race cat to go along with it. Either way....good luck!

I would much rather use a stock jdm part over any aftermarket part... Especially that the two headers are almost identical....

I would much rather use a stock jdm part over any aftermarket part... Especially that the two headers are almost identical....