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-   -   $1000 for racing beat exhaust?!? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/%241000-racing-beat-exhaust-1109305/)

billyjones454 01-09-17 08:28 PM

$1000 for racing beat exhaust?!?
 
I really want to update my exhaust, but damn, that's steep for my budget. Any alternatives?

I have seen a 13b header on eBay for a couple hundred, and thought about getting a universal exhaust kit, but thought I'd ask you fine folks if there's a downside to that route other than the time, and probable quality (since I'm the bastard that'd be welding it together).

Thanks y'all.

Qingdao 01-09-17 09:09 PM

It'll work. Don't even try to put a resonator on there. I've tried several brands of pre-silencer and they've all melted or otherwise blown out their packing. Like I said it will work, but that's about it.

Use the Flowmaster brand pre-bent piping for about $100 and a canister. It'll get the exhaust gasses out of the engine bay and to the rear bumper for under $200. N/A it is quite loud. Turbo its not so bad, but still pretty loud.

Lots of people like the thick walled piping.

One day when I'm a rich guy I'll get an RB pre-silencer, thick wall piping, and a power pulse canister. BUT till that happens the Flowmaster piping with the ebay muffler is serving the purpose of getting exhaust out to the back of my car.



Get the RB header. That close to the engine you want as quality of a pipe as possible. Rotary exhaust isn't something to play with that close to the engine. I am using flowmaster stuff, but I have an OEM Mazda downpipe from my turbo and I'm using a Mazda exhaust manifold.

Sh00bs 01-09-17 10:37 PM

wait for a used system to come up. RB is worth it

billyjones454 01-10-17 01:32 AM


Originally Posted by Qingdao (Post 12140131)
Don't even try to put a resonator on there. I've tried several brands of pre-silencer and they've all melted or otherwise blown out their packing.

Get the RB header. That close to the engine you want as quality of a pipe as possible. Rotary exhaust isn't something to play with that close to the engine.

I'm still getting aquatinted with rotaries. Can you elaborate on why a cheaper header might fail more readily on a rotary vs a piston engine? I assume that the silencers failing is related?

Thanks.

Zepticon 01-10-17 02:08 AM


Originally Posted by billyjones454 (Post 12140193)
I'm still getting aquatinted with rotaries. Can you elaborate on why a cheaper header might fail more readily on a rotary vs a piston engine? I assume that the silencers failing is related?

Much higher exhaust temps than pistons :)

t_g_farrell 01-10-17 07:53 AM

If you buy a RB full exhaust system new or used you will likely never have to replace the exhaust
for the life of the car. Anything else will burn up over time and be noisy. Also the RB system (SP)
is a dual to the rear axle which makes it a very well tuned exhaust system for a rotary.

Why the thick wall construction and expense of the RB system, one word, heat. The rotary
exhaust is ~1800F compared to most piston engines that run at maybe 1200F. The thick walls
help muffle the tinny noise from the N/A rotary and also can withstand the heat. Any other
header like pacesetter etc will burn up (literally) within months if not weeks of installation.
Don't even think about using glasspacked anything for silencers, they melt. Silencer need to
be stuffed with stainless steel wool or a ceramic fiber wit withstand the heat.

FührerTüner 01-10-17 08:12 AM


Originally Posted by t_g_farrell (Post 12140235)
Silencer need to
be stuffed with stainless steel wool or a ceramic fiber wit withstand the heat.

This is the only difference really, as far as the resonator and muffler.

Qingdao 01-10-17 08:49 AM

RB needs to make a turbo FB exhaust. I'd buy that.

Just a 3" BYO down pipe system.

Baaaa I'll just save up for a year or so and get what I need to make it.

billyjones454 01-10-17 10:11 AM

Thanks everyone great info, and great community.

mhr650 01-10-17 10:26 AM

No question about rotaries being so much harder on exhaust than piston engine cars. I fought for a couple of years to keep a system reliable on my race car, endurance racing a rotary is the worst case of all since the exhaust gets hot and stays hot for so long. Finally I scrapped the whole system and started fresh, everything from front to back is stainless steel. I am using a custom stainless header, Racing Beat pre silencer and main silencer, 3 inch stainless tubing, and v-band connections. The last race was at AMP which is one of the most strict tracks in the country on noise and it was the first time we have avoided a noise problem at this track, and it seems like the system held up just great. In the end I probably spent at least $1000 but it will be worth it in the end.


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