soo, after a few months with my 3" asura exhaust, i had experimented with a berk 63mm test pipe, then a 63mm t1R resonated test pipe, and now a berk HFC 70mm.

i specifically compared the sound readings of the 3" asura exhaust with 63mm resoanted test pipe and the 3" asura exhaust with berk 2.75" 70mm HFC.[media]http://www.youtube.com/watch?v=QLAIcbp8l-8 [/media]

first, readings with the 3" asura exhaust and 63mm T1R resonated test pipe
rear of car 86-88db
front passenger corner of car 83db
inside car drivers seat top down 92-94db

RTP made exhaust sound deeper then test pipe across the whole rev range.

readings with berk 2.75" HFC 70mm installed
rear of car 84-86db
front passenger corner of car 78-79db
inside car drivers seat top down 88-89db
inside car drivers seat top up 86-88db

i logged my map sensor after the HFC install, and saw at most .2psi of boost increase, so the 70mm HFC flows damn near just as well as a 63mm resonated test pipe


bottom line, berk 70mm HFC flows pretty much like a 63mm resonated test pipe and reduces peak volume anywhere from 2-6db

i am a very happy guy

thanks bryan and laurie

http://www.berktechnology.com/

 

very nice!

 

Did you ever have just a plain TP, or have you always ran the RTP? I was curious to see the difference there as well.

Howcome no 3'' HFC?

BTW.....nice app for that test!

 

berk doesnt offer one at this time, asura had none in stock and no clear ship date, and the ULT RACING 3" HFC was a totally different design then the other two.

SOOOO, i figured, as long as it flows as well as a 63mm test pipe, i didnt care that much. in the end, the header collector is only 63mm anyways, so i dont think i will gain much a anything with 3" vs 2.75" for that one small section of pipe. Berks HFC really does flow well

 

good deal, I will be running this same setup. Its good to hear positive data on it.

 

My Random Tech HFC seemed to be louder than the TP. I took it off for hp gain obviously, but if it is THAT close in comparison then its really not worth it to go TP. Of course no one has tested the Random Tech HFC since all these other companies offer them now.

I'd like to be able to test mine, unfortunately i know nothing with my EMS. Nor do i have a Db meter. :-/

 

find a friend with an iphone, and i think it was 2 dollars the the db meter program. i tell ya, that damn iphone can do near everything except cook me breakfest.

there was another post in FI forum of a comptech blown car that boost went up .1psi and he documentated with a dyno a loss of 2whp in only a few parts of the rev band. i saw mine at the map sensor, .2 peak increase. to me thats negligible.

berk HFC 70mm

 

That was all done at idle. Would've been interesting to see the differences at 3k rpm.

 

Nice. Looks like i'm selling my 63mm HFC..