Looking for some guidance on what the most economical step to take would be in making my RB setup even quieter. Currently I have this catback with the RB downpipe and pre-silencer http://www.racingbeat.com/RX7-1986-1...sts/16420.html on an 88 N/A.

Over the years the sound has begun to bother me and I am wondering what my alternatives are for quieting the system down to stock-like levels. I don't really care about negating the performance gains this setup may have given me as my priorities have changed with car but I really don't want to incur the cost of replacing the whole system with a stock system.

Is there a high flow cat or something that I can have RB flanges welded on to and bolted in place of the downpipe/presilencer combo that will shut this thing up??

I know weird question but like I said my priorities have changed over the years since I had the exhaust fitted up and I no longer want the drone!

Any help/advise would be very appreciated.

Thanks!

 

that is considered one of the quietest on the market, short of removing the cat back and maybe putting on a walker or a borla I dont know what you can do, maybe another resonator somewhere?

 

I know its the quietest system on the market. Thats why i bought it originally. Now, I find my self taking it down to stock but im looking for an economical alternative as I believe mazda will rape me on oem main and precats.

This brings me to another question. If I dump the downpipe/presilencer for an oem main and precat would that silence it at all or is the "sounds" of the exhaust really coming from the cans? I have my oem cans and ypipe but got rid of the cats because they were shot.

I feel stupid asking these questions as I used to know a bunch about this but my interest faded a few years back and forget most of it.

 

I would consider adding another resonator

I went from pre silencer to high glow converter and there was not really any difference in sound

 

I had that exact problem with my AutoVert with exact set up. Louder than either TurboVert with the REVII. Wanted to quiet down since it was the DD.

Fix for me was to replace the RB cans with stock cans retaining the RB downpipe, presilencer, and Y pipe. As additional reference, I didn't feel any noticable seat of the pants performance difference. But you do loose the RB shiny bling. I could not detect much if any sound difference just by changing out the RB downpipe/presilencer for stock precat downpipe and main cat.

You might be able to attain your goal and retain the RB cans by buying one of RB's universal 3" presilencer and having your local muffler shop weld it in. You can also get the proper mounting flanges from RB. But I kind of think the lower back pressure a 3" version would provide might result in a slight hit to performance. There is a reason RB designed the NA presilencer the way they did.

As to reducing sound, apparently bigger is better. Cut and paste from their web site:

Racing Beat offers two versions of our 3-inch ID Power Pulse Presilencers for use in the design and manufacture of a custom exhaust system for your street or race vehicle. Well-suited for the demands of high-power turbo applications, the oval-shaped 3-inch ID presilencer can be adapted to fit into tight spaces under your car. Manufactured using 304 stainless steel inside and out, this presilencer unit offers sound reducing performance at a very reasonable price!

The size of this presilencer is: 6.25" Wide x 4.875" High x 15.75" Long. For increased sound compression, we offer a slightly larger version which measures: 7.25" Wide x 4.875" High x 15.75" Long.

 

if you want quiet higher flow alternative to the OEM n/a exhaust, find a used TII catback.

the stock system actually flows VERY well, moreso than most people give it credit for. i can hardly notice the difference powerwise between it and the 3" single open exhaust at 350WHP levels.

most people just don't like the stock exhaust tone, but it is the quietest exhaust you will find.

 

I'll buy your RB setup so you can buy OEM replacements =D

 

Thanks Hozzman and Karack! Your input is appreciated. I really love the look of the system but perhaps I should be considering just swapping the whole thing out for a stock system. If only I could find one!

Against the grain of what ppl are doing on this forum I know but I really like the car, just don't care for the aftermarket noise anymore.

In which case TeamFervor yes, it would be for sale!