Originally Posted by 88 SE (Post 11810940)

The silent hi-power is specifically made to be much quieter than other products available. HKS lists noise level of 99db compared to stock 85db.

Originally Posted by JoesFC (Post 11811139)

I know but when catless it would definitely spike upwards

Originally Posted by 88 SE (Post 11811634)

That applies to all exhausts. There isn't one that exists that isn't made louder by no cats. The catalytic converter has to be replaced with a center muffler or resonator if you want to keep the sound down.

Originally Posted by JoesFC (Post 11811685)

Well of course. The point of this thread is asking if anyone has experience with this combination of parts and would give input as to whether it would be reasonable for a street setup in southern california. Or alternatively if anyone has any other possibly better alternatives.

Originally Posted by 88 SE (Post 11811821)

That's the point I was speaking to. The silent Hi-Power is one of only a handful of exhausts for FC's that are JASMA certified meaning they meet the strict noise guidelines Japan has.

I have had it before , as well as a handful of other exhausts. And none of them are what I would consider "reasonable" without a cat or resonator replacing it.

So the answer to what would be a good sound without "being barbaric" is any combination of cat/center resonator + JASMA rated catback. Dual systems will always be quieter than single systems...

My personal pick if you want to take the time to find one is the Fujitsobo Legalis R . Higher flow than stock but quieter over 3000RPM it would probably be the most tolerable exhaust made with no cat. No joke, the sound data shows it to make LESS noise than a stock exhaust but still giving a "dyno tested" 6hp gain on a stock car.

Originally Posted by 88 SE (Post 11811821)

That's the point I was speaking to. The silent Hi-Power is one of only a handful of exhausts for FC's that are JASMA certified meaning they meet the strict noise guidelines Japan has.

I have had it before , as well as a handful of other exhausts. And none of them are what I would consider "reasonable" without a cat or resonator replacing it.

So the answer to what would be a good sound without "being barbaric" is any combination of cat/center resonator + JASMA rated catback. Dual systems will always be quieter than single systems...

My personal pick if you want to take the time to find one is the Fujitsobo Legalis R . Higher flow than stock but quieter over 3000RPM it would probably be the most tolerable exhaust made with no cat. No joke, the sound data shows it to make LESS noise than a stock exhaust but still giving a "dyno tested" 6hp gain on a stock car.

Originally Posted by Dak (Post 11811935)

For what it's worth all FC's in Japan were turbo models. That would have an effect on their results. Sound and power. It's how the turbo guys get away with running singles but n/a guys struggle getting the sound down. The turbo helps muffle the exhaust some.

Originally Posted by JoesFC (Post 11811928)

Solid info. Thinking im gonna stick to the silent hi power though. You ran it catless?

Originally Posted by 88 SE (Post 11812124)

Yes and it was mildly aggrevating.

The silent HiPower is one of the quietest bolt on exhausts for an FC, but without a cat it's still going to be pretty noisy. It's about on par with a honda with a fart pipe for noise. There's just no way around that without a cat or presilencer.

Originally Posted by 88 SE (Post 11813124)

You should be ok then