No tuning was done. The A/F ratios didn't change much after the header install. So we left them as they were. The dyno runs were done about 2 hours apart on the same day. No test pipe was used.

 

Those gains don't look right you need to get it done by Church Automotive.
Also do you have a EMS on the car?

 

Is it possible that the Mugen exhaust is the restriction? May be the Mugen exhaust is too small for a supercharged S. Therefore, even the ASM header give better flow, but it was restricted by the exhaust.

 

in that case he would dyno in at 678rwhp with a gain of 78rwhp from the header. And because he is so amazing, he would get the power up to 870rwhp from tuning.

 

Hmm very surprisingly small gains given it's with a SC.. I was somehow under the impression that most aftermarket headers would yield good results with an SC.

 

Do you think you'd see more gains with any fuel or timing tweaks/tuning? The numbers are fair, but I'm wondering if a person could get more out of it with some additional tuning. Just my own personal curiosity.

 

Was there any expectation that the ASM header was designed for FI applications? I thought it was intended to run with their airbox. Also the Mugen exhaust is designed for NA applications as well.

You would probably see much higher gains with a Toda header and higher flow exhaust+test pipe.

 

c'mon ASM

 

 

If the header is only showing that much hp gained on forced induction it further confirms that it is almost an exact copy of the toda header. Which yields less then 2hp in n/a form. The mugen exhaust is not getting in the way of the headers performance. The header is just bling and now it has been confirmed. Asm=Toda=bling. In the future if you guys are going to spend that sort of coin, go hytech or burns and get some real power. I wouldn't be surprised if the megan tested the same or higher. At least the header is nice to look at.