DC-Sports headers are great headers and have beaten a lot of other ones in SCC or SS magazines header tests over the years. DC-Sports Headers are also CARB excempt, so that's a plus for states with emission testing. DC offers a JDM 4:1, which has a bigger collector, but is meant for racing and might not pass emissions. They also offer a 4:1 and a 4:2:1 header. The 4:1 provides best results in the mid to upper level of the powerband. The 4:2:1 provides the best results at the low to mid end of the powerband. It just depends on where you want the most amount of power in the powerband. The 4:2:1 is better for off the line, but the 4:1 is better in mid to high range. DC-Sports just updated there website
www.dcsports.com and they use to have a dyno test on a 99 civic si which is the b16a. I know you have the d16, but what was interesting was seeing the dyno results between the 4:2-1 and 4:1. For some reason the dyno page isn't coming up, well for me it isn't. But when the tested the 2 against each other you could see the difference. The 4:1 was a little below the 4:2:1 at the low end but at 5400 rpm (around where DOHC VTEC kicks in on the b16) then the 4:1 spiked up a lot more over the 4:2:1 and remained above the 4:2:1 the rest of the powerband according to there dyno results. Maybe the will fix there dyno link soon. Anyway, hope that helped. I have the 4:1. I am not sure about the shifter, but they use billet aluminum, which is really good quality.
Blair 95 VTEC
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