MB

I am modifying my S and will have quite a few bolt on mods with AEM EMS mapping. I have a J's manifold and 3" decat at the moment but more bits to come.

I want a light single, but I don't like noise. For me the Mugen AP2 is perfect, maybe a bit louder!

So which one of the two ASM exhausts is quieter?

modMonkey

60mm, but you sacrifice a bit of performance. A 60mm makes a 3" cat delete pointless. Depending on your delete, it may not mate up well with a 60mm exhaust.

Chris_Lum

do you know how large the collector on the J's header is? the 'official header thread' only says 55-60mm. If you go from a 60mm collector > 3" test pipe > 60mm exhaust there will be a bunch of turbulence when the exhaust flow hits the 3" section and has to taper back down to 60mm. If you know you want a 60mm exhaust, replace your 3" test pipe with a 60mm test pipe.

It's best to either 'step up' in exhaust flow as it exits the vehicle, ie. 60mm collector > 70mm test pipe > 80mm exhaust or stay the same, ie. 60mm all the way through (or even partial step up 60mm collector > 70mm testpipe and exhaust) etc... step up, stay the same diameter, just don't create a restriction/taper if you can avoid it.


for your question, of course the 60mm will be quieter, but the ASM 70 is not loud by any means, even with a test pipe. So if you want to make power, your best bet would be to switch to a 70mm test pipe and get the ASM 70.

FISH22

I have had the ASM 60 for almost 2 years now. When it was new, it was extremely quiet. But it has definitely gotten louder over time. The ASM exhausts seem to do this, mainly due to the internal sound dampening material wearing out.

modMonkey

I would run a 70mm ASM if I were you. It isn't loud at all and has an extremely clean sound. I've only had brief experience with the 08 Edition (with the helmholtz resonator), for some reason, it would vibrate the cabin at a certain RPM. This is with a stock cat. I imagine a cat delete would clean up the tone.

MB

Thanks chaps.

Chris, I agree with what you are saying and have a smaller Berk test pipe sat in the garage in case I go for the smaller diameter all the way through.

Fish, have you had any issues with yours? I think being stainless it should be ok. I have a very expensive Amuse titanium ornament in my garage and think the ASM should be reliable.

Monkey, i've had a few S2000s where the decat has cured the drone, so hopefully this will be the case

FISH22

No issues whatsoever. Has about 10k miles on it, and still looks new.

s2konroids

Mark PM 'sneakfish' form uk forum, he had an ASM singlepipe 70mm

MB

chrisr111

Mark,

Rick (RedUn) in the UK used to have an ASM single on his S2000 before he sold up and bought his Porsche. It might be worth asking for his opinion.

Chris.