A while ago the motor popped in my ’91 non-turbo and I’m currently finalizing the plans with the engine builder for the new setup. What we’re looking at right now is a full rebuild using new TII housings, some porting of the exhaust and intake, a RB header going to a Bonez cat out to a RB catback. Some of the other goodies we’re throwing in will be a RB aluminum flywheel, mazdaspeed engine mounts, SS oil lines, and maybe the pineapple sleeves.

My question is, with this setup, am I setting myself up for having a ridiculously noisy ride? I’m concerned that even with the RB catback… no exhaust diffusers + headers + porting could equal a deaf driver. It’s not going to be a daily driver, but I still want to enjoy it when I do drive it. Anyway, I’m looking for some thoughts on how loud (or not loud) this may be while there is still a chance for some changes.

 

my n/a is street ported, no diffusers, full RB exhaust, and its LOUD

 

Do you think the majority of the noise comes from the lack of diffusers, the headers, or from the porting?

 

Mines that way, ported header no port exhaust sleves, high flow cat . mine sounds like two drums banging when at idle. i love the sound. but this weekend i put two resinators on it , so its a lower sound now . but yes it will be loud, and mine being a vert u here everything. oh well. enojoy!!!

 

Its going to be loud, but not undrivable. The RB mufflers do a pretty good job on quiting things down. Just be warned that it gets kinda old on long trips.

 

Thanks guys! I'm going to go ahead and build it using regular non-turbo housings, keep the diffuser, and do everything else mentioned. I'll let you all know how it turns out in about a month.

 

Loud to one person is quiet to another. Some people say that RB's exhaust is too loud, I think its too quiet (if that makes sense) and so on.

I say that the fact that you have the cat and RB muffler you'd be fine WITHOUT diffusers. Its just a matter of what you perfer.

Might as well snag that extra bit of HP .

 

it will be so lOUD it will BREAK your EA DRUMS

 

With a cat and RB mufflers?

Hardly...

 

OHH MAN IT WILL BREAK YOUR EAR DRUMS, NO JOKE MAN!! well if you rev to 9K with no exhaust manifold at all maybe.... lol

 

holy **** no exhaust manifold ??? thats crazy...maybe open headers will be loud as ****