PaperNinjaRotor

Hey guys, I'm working on an exhaust system for my FC, and I've be doing ridiculous amounts of research from Racing Beats website to the fantastic search tool on this website, as to creating a custom exhaust for my FC, and this is because I do not have $1,500 to buy the Road Race system from Racing Beat, i tried attaching a zip file to this thread, maybe it worked maybe it didn't, if it did and you can't open the compressed file, change the file type to anything that will work on your computer, It was drawn on a design program I have on my MacBook, very hastily I might add, what the file shows is one of the ideas I'm thinking about using, I have decided to get some feedback from you guys, just to see what you have to say about it.

It consists of switching from dual outlets (stock exhaust) to a custom single outlet exhaust created from racing beats universal exhaust parts, and the stock header.
What I am thinking about is running racing beat 2.5 OD stainless piping to a racing beat 2.5 universal pre-silencer, and then into the racing beat megaphone outlet. The one that slowly goes from 2 inches to 4, so as to not randomly open and lose all velocity.

This is just an idea, but it won't cost me much to build, I work at a mechanic shop where we do exhaust work, so fabricating it won't be a problem once all parts are bought, but is this a good idea?

Other Mods are Half BridgePort, emissions and all removed properly, with everything that needs to be blocked off, blocked off, real cold air intake, its blocked off from rest of engine bay.

Feedback will be much appreciated, Thanks!

Dak

I couldn't get your file open but based on your description here are my suggestions. Since you said you have a half bridge I would throw a header in the mix as well. On Their( RB) site they give 22" to 25" inches for the short system length for a streetport or bridgeport which is pretty close to what their collected header is. Also with just that pre-silencer it will be too loud so I would cut the megaphone at 3" dia. and run that to their 3" universal muffler and your tip of choice. You may still be too loud and have to put a third muffler or resonator in as needed. Some have said 2.5" is big enough for a n/a so you may not need to go to 3". The 2.5" muffler may help with sound.

Or you could do what I may do since my catback is faling apart from rust. I have the RB header /pre-silencer already. You could make you header/pre-silencer end where the stock cat ends and then get this cheap ebay system: http://www.ebay.com/itm/Mazda-RX7-86-91-FC3S-3-Turbo-II-Cat-Back-Exhaust-Muffler-System-Stainless-Steel-/231287940283?pt=Motors_Car_Truck_Parts_Accessories&fits=Model%3ARX-7&hash=item35d9d5e4bb&vxp=mtr#ht_3140wt_1324
Then add in a small muffler/resonator of some sort into it. Something like this: Dynatech 776-06302 Dynatech Split-Flow Race Mufflers - Free Shipping on All Orders @ JEGS
and be done. just make sure any muffle has stainless packing.

PaperNinjaRotor

Thanks for responding man! Sorry about that file, thats my fault, new design program and trying to make files that will open on others computers, I could've done a better job with that, but nevertheless.

I was looking on Racing Beats website this evening, I definitely want to do the single outlet on my car, and noise isn't much of a problem, my mechanic shop does all the work on all of the law enforcement in my area vehicles, and half of them tell me I need to make her louder anyway, but I don't want anything earsplitting, my dad has a GT500 that I can't drive because the exhaust is so damn loud, so I was thinking the Road Race header, with their collector, and that is 2 inch outside diameter piping, and then running the their 2inch universal pipe into one of their (racing beat) mufflers and a Greddy tip (fart can) with a silencer if needed, at the end.

How does this sound? I want my port to breathe!

misterstyx69

iTrader: (142)

Take the RB Collective header and go to a presilencer,the run to a 3 inch RB universal can.
You only have to make pipe from the Pre to the Can.

Dak

I drove my car with only the header and pre-silencer once just to see what it sounded like. It was very loud. It didn't sound bad but was to loud to drive on the street everyday. If you went with their( Racing Beat) road race header I would throw their road race pre-silencer in there then their collector/megaphone as far to the rear as I could .Cut the megaphone at 3" and straight into their 3" universal muffler. Only problem with this is without being able to test exhaust on the dyno it is hard to know exactly where to place the collector. It's just a guess really.

Or you could do like misterstyx69 suggested and get their collected header and pre-silencer combo and only build the cat-back part. If you don't have access to a dyno this may be the best bet as I had mentioned earlier their collected header comes out to be what they reccomend for a short primary system.

Down towards the bottom is where they talk about primary length.
http://www.racingbeat.com/mazda/perf...gurations.html

PaperNinjaRotor

I have actually read that before, and thank you guys for the ideas, but could someone explain the long primary and short primary thing to me. Like I said I have read that before but to be honest I don't really understand the whole thing, and explanation would be wonderful.

Dak

The individual pipes that make up the headers are called the primaries. Where they are collected at dictate whether they are short or long primaries. Appox. 25" or less would be a short system. 80" or longer a long primary. Most say Racing Beat's guidelines are a good place to start. Search for exhaust threads that j9fd3s or Rotarygod are in, in the normally aspirated performance section and they give some pretty detailed explanations.