peejay

My current system is about as loud as the long primary RB system my friend had on his '79. So, not quiet.

I've been thinking of duplicating that system, but with four presilencers dumping into one 3" baffled muffler with a 2.5" restrictor cone on the inlet and a 2" cone on the outlet.

This car came with a non-RB system (Mind-Train?) that WAS really quiet, almost like stock... and it made power like stock too. The presilencer was a louvered-core glasspack style muffler with a maybe 1.25-1.5" core. Replacing that with a catalyst made the car a lot louder but it also passed emissions too. And made a lot more power.

The video on my YouTube channel of my streetport 13B dyno pull was with that header, muffler, and a hollowed out catalyst. (And factory 12A midpipe, IIRC) Current system is a little quieter than that. Still too damned loud.

diabolical1

iTrader: (3)

my days of going out of my way to have a loud car are long gone, but while i don't necessarily want a loud car, i'm not against it either. i plan to race my current Gen I whenever i get around to putting it back together, so noise is a given. however, i will have to get another FB at some point to run on the street and i already have my RB streetport system for it when i do. so not much noise there.

the FC, on the other hand, when it comes together i will be designing a custom exhaust and i've already become one with the fact that that system will likely be loud! - at least until a turbo gets involved. i plan to make an honest go of it. i want to make a real effort to tune for maximum relaible power.

peejay

I drove fidelity101's FC at the last rallycross I was at, his car is actually pretty quiet! And it felt like more power than my car despite his having a 44mm Mikuni, which should suck in theory. Maybe it just felt more powerful because it was so much quieter, or maybe it was because HIS engine doesn't have to stop the party at 8k like mine does. (At one point I was chickening out and lifting at 9k well before the first corner... he wasn't lifting but he wasn't upshifting either ) The percieved power different could also be down to his shorter tires, different gearing, etc.

But the point is: One advantage of the FC is that there's a lot more room under the car for mufflers.

RotoricanNY

iTrader: (2)

I have a dellorto 48dhla with full RB exhaust and suspension, while it's not as fast as a boosted 13B, but it's great to DD, hasn't given me any major problems.

j9fd3s

iTrader: (3)

yeah the FC is EASY, actually you just run the RB turbo back/rev II presilencer in the center, and then the rear muffler just provides the tone.

we ran the usual dynomax can in the ITS car for something like 115DB, it was LOUD even for a race car.

we put some 3" chambered POS that came apart every time the car ran, in the center, for like 103ish

the RB part dropped it to 98DB, which is quiet for a race car, and 3 seasons on a dynomax probably means its dead....

and then it melted, but it WORKS

aa35199

iTrader: (1)

Thank you every one for your replies, this has definitely given me a lot more insight into the potential this humble little car is capable of. Hearing all of your stories really makes me want to show my face at a 7 meet.

BTW
Awesome I couldn't have said it better myself. After my V8 swap I went from fielding questions from young enthusiastic would be rx-7 owners to old gruff hot rodders who were more in love with power to weight ratio then the car as a balanced whole. Not that I'm not proud nor happy with my car, it was just a stark change in demographic.


My stockish 12a with an RB exhaust got me fix it tickets from policemen who group me with loud honda civics, and my v8 has gotten nothing but curiosity and interest from the few pulled have pulled me over, I have learned cops love muscle cars and dislike any thing with a loud(ish) high pitch exhaust.

Thank you again to every one for their views and input!

pjr

iTrader: (8)

I have the best -- or worst -- of both worlds, pending on your viewpoint.

My Cartech install still has the Cartech exhaust on it. It's deep and rumbles, especially with that little lope from the streetport. Sounded very comfortable on the cruise scene among all the muscle cars.

However, it is a bit loud, and time on the freeway can be a bit much.

Of course, the exhaust is old, so maybe it's starting to fade away. Sounds like RB really doesn't quiet things too much.

j9fd3s

iTrader: (3)

i took my 3 rotor FC to sevenstock (in 2002), and i was parked across from a guy with a v8 FC, and we BOTH made it into the japanese Rx7 magazine. go to meets!

pjr

iTrader: (8)

A 7 meet? I could only dream.... I probably see about a dozen RX-7 of any gen all year.