The reason why I'm considering the Mugen AP1 header is b/c I found a used one available at a reasonable price.

 

I do recall reading that the only change to the exhaust was the tips.

 

was the car tuned? you will lose top end power with this header. the car basically stops making power around 7600rpms or so unless you get it tuned. then you pick up most of what you lost up top with the exception of a few hp.

this is a low to midrange header and it makes a difference at those points. like a 6-8hp difference throughout the whole low to vtec point.

 

^Are you asking about the King Motorsport AP2?

 

nevermind...just re-read. i see they put the ap1 header on the ap2. thought they were just talking about putting all mugen parts on an ap2 (including ap2 header ) and losing power.

regardless, ap1 to ap1 and ap2 to ap2....my statement still stands

 

Go ahead and put the AP1 mugen header on an AP2 engine. My dyno guy said the difference in horse power pretty minor.

 

^does your dyno guy have any dyno sheets?

 

In case anyone else finds this thread in the future and wants to know, the difference btw the two headers (basically Philbert was correct, not sure which was increased/decreased though).

From the Japanese Hyper Rev Magazine, as translated by ///KM:

"Mugen AP1 and AP2 headers, and describes that the AP2 version was developed specifically for the AP2. Using the AP1 version as a base, they altered the length between the exhaust ports and the collector to optimize it for the 2.2L engine. Guess that's it. Mugen site describes the same thing."


https://www.s2ki.com/forums/index.php?showt...post&p=18110648

No answers to gains of Mugen AP1 header on AP2 an vice versa though.