on my 89 supercharge RB full system is the best bet , expensive but good quality

 

I'm building a Locost w/ a large streetported N/A 13B. The muffler's basically going to be right after the collector, so it's going to be seeing some pretty high EGT's. Do any of you guys know a long round muffler that will handle this kind of temps? Magnaflow makes a 27" long 6" round but that only uses partial stainless packing and the fiberglass packing around the outside of the muffler will melt. thanks.

Steven

 

rb header, straight pipe, borla xr1 exhaust. so far havn't gotten pulled over

 

so from what i'm hearing 2.5"- 3" is around a good size for the tip eh? how big can you go before you start losing power on an NA?

 

Looking to incorporate the best header, cat and exhaust. Can fabricate something if I have to but don't need to re-invent the wheel. For SCCA Solo2. STS(2) class.

 

I have racing beat true dul i love it makes good power not to loud.

 

Well you can do RB if you want moderate gains, but really want it quiet. If you want power you're going to have to be okay with a loud car. I personally hate RB exhausts.

https://www.rx7club.com/1st-generation-specific-1979-1985-18/racing-beat-exhaust-dyno-compairisons-823229/

 

anyone try the rotary performance exhaust?

 

The last I heard it was discontinued. The site hasn't been updated in years.

 

too late for me now, I already own it lol and its been on there for years

 

i have one on my gtu just wondering if anyone else is rocking it and how they like it. I'm debating if i should change it or not...

 

I have the Apexi N1 Duals on mines, i love it.

 

I have the RB true duals on mine, I think it sounds great but I can't attest to power gain since I have yet to drive my FC, 5 years of ownership and I drive it for the first time this weekend.

 

My friend Justin bought the RB True Dual exhaust, waste of money if you ask me.

My Friend Bobby has a OBX Header to the RB cat back (has cat delete pipe installed) and it sounds great and has helped the engine breath.

I have the OBX 2.5' Header to a 3' cat delete pipe to a 3.5 'muffler (this is a single exhaust) and I love it.


People praise the RB true duals but I dont think there great at all. I think there over priced and over hyped.


I paid around 400.00 when all was said and done for my single exhaust....or you can pay 1000.00 + for a true dual exhaust that will get less to the same results as mine

 

well...this doesnt apply to that gnarly setup with itbs, but my fav 2 are the old school hks and the PROF exhausts for 2.5 and 3 inch respectively

 

There is no "best" exhaust for an n/a. There are only systems that have advantages or disadvantages over others in certain areas of the powerband or in regards to noise control.

I've always thought it funny that people on this forum will insult a Pacesetter header as a total piece of junk but don't seem to realize that the OBX header is the exact same design! It's made from a better material but it's still the exact same unequal length, poorly designed collector of a system. It is much better than a stock manifold though.

The Racing Beat header is a nice piece. Good power gains and as simple as can be. Definitely an improvement over stock and better than the OBX. I know Hyper swears that RB exhausts suck as the way he had it setup, it did, but forum member Kahren has dyno'd 190 rwhp on a RB header using stock intake ports, a custom intake manifold and a standalone ecu that was tuned very well so it can't be that bad of a piece.

The true dual system is a good option for a stock or streetported engine. It gives a very noticable gain over stock and is decently quiet. Sound is a personal preference though and I've always though a true dual system on a rotary is about as terrible sounding tone wise as you can get. The farther forward a system collects, the higher pitched the tone will be. The easier it will be to muffle as well. The farther towards the rear is collects (or not at all), the harder it will be and the lower the tone will be. That doesn't mean it will sound like a V8 though. Something more along the lines of a Harley crossed with a lawnmower.

You've got custom designs such as long primary and short primary systems. A short primary does not necessarily make more top end power than a long primary. It all gets technical to the point that I'm not going to explain it all here but needless to say we typically tune an exhaust to the 2nd wave reflection rather than the first. If you could assign a stength of wave value to each in terms of percent than the 1st reflection would be around 10%, the 2nd around 7%, the 3rd around 3% and the 4th around 1% with no benefit after that. Theoretically a pipe with tuned to an R value of R1 would be twice as long as R2 but it doesn't quite work that way due to the speed of sound changes in the pipe as the gasses cool.

As I said it gets technical and it too much for the scope of this thread. Suffice it to say there is no one best system. All too often people ask the question hoping to get a response that directs them to the system that will give them maximum power over all other systems. They will never get this response though. If it were even possible and there was only one best system, everyone would use it. Clearly we've seen a number of opinions here so that isn't the case.

 

??if i take the 3 cats out of my n/a 87 fc will the engine need to be tuned to run with out them, i heard the engine can blow without tuning. and will it add any power??

 

I have the header back exhaust from Corksport. I love it! But......ha I am going to have to get a presilencer and possibly an actual cat to quiet it down a bit. Had to many looks from cops. Mind you the silencer tube from the muffler is pulled out because it sounds like a Honda with a walmart muffler with it in.

 

Wow a lot of rb fans.
I would be too i guess if i can afford one ha
I have hks hi power and love it

 

I have 3 inch pipe all the way back with a tanabe muffler and I love it

 

88 has rb true header x pipe cherry bombs and flow master 40s at bumper and tips inlarged to 4 inch this system is 2 inch all way to flowmasters

on my 89 rb non dual header resonator from a toyota camry ran into a one in two out straight thru muffler with magnaflow cans this system is 2.5

 

holy hell was tired last night the flow master tips were made into 4 inch and the header on88 is true dual x pipe is right after header and then is true dual with the bombs all way back to flow masters

and i always try to run dual cuz your dividing up how much exhaust the muflers have to quit down and usually runs less back pressure

 

racing beat dual catbacks with no cat. all straight pipe!

 

My money is going to Racing Beat for sure XD

 

Talk to Logan (GtoRx7.) at Defined Autoworks. He has empirical evidence of what works and what doesn't. His work is backed up by dyno runs.

If you really want the best N/A exhaust, I don't think you are going to find anyone with more knowledge.

Read this thread he has;

https://www.rx7club.com/1st-generation-specific-1979-1985-18/looking-r-d-testers-defined-auto-promo-headers-935940/