ddub

Hey all!! First off i just wanted to give a whats up to everyone, im a proud new owner of an 88 rx7 gxl as of a couple days ago and i am LOVING it!! i have a couple questions, but before i go into those, how bout some introductory pics of my car

ddub

Alright, now for the question of the day...what exhaust system do I have? the dealer that i bought it from didnt know because the previous owner didnt tell him...ive been looking at various rx7 systems online but im not sure, so i thought i'd ask all of you...here are the pics of my exhaust system so any info on it would be appreciated














Well thats it...if you know what exhaust system this is, plz let me know, and also...is this a good system? or will i be able to put something new together to get more performance out of it? if i can what do you think is best? ive read and searched through TONS of posts on here about ehxaust systems and it seems like everyone has a different opinion on whats best so any suggestions would be great

also, my rx7 fails emissions TERRIBLY lol but i dont have to pass it until sept of 2004, from what i can see under the car, there's no cat, the thing in place of it looks like a presilencer or something? not totally sure...my question is, will the rx7 pass emissions with a high flow cat?

thank you all for your input and help, and ill be seeing you around!

Wompa164

iTrader: (4)

I want to say the RX7.com Rotary Performance 50mm exhaust. I can't be sure though, but that's what it looks like.

Also looks like the Bonez Hi-flo cat, but not sure again.

ddub

hmmm, if thats a hi flow cat, then how come im failing emissions so terribly? are there other things i should look at if that is indeed a cat?

Davidov

iTrader: (2)

The headers and pre-silencer look like Racing Beat products.
Not sure about the rest, but it's definately unique, the way the "Y-split" separates.
It could be a custom job, or an old school cat back system.

I saw a old HKS cat back that had similar mufflers to yours, but who knows.

That's a good setup for power, but like you said it's not emissions friendly.
I passed emissions just fine with a 145K mile motor and a new hi-flow Catco catalytic converter.
So when it comes time for you to get tested, either find a good friend at an inspection place or buy a new cat.

Mr. Eccentric

That's an old style HKS exhaust. I'm not sure if they still make them for FC's or not. Not sure about that presilencer, strange that there's even one there those cannisters are pretty quiet as they are.

Welcome to the forum

ddub

thx for the welcome

and that system actually isnt very quiet heh...at full throttle its pretty damn loud, but anything is with no cats right

Dak

I believe the header and pre-silencer are Racing Beat.The mufflers look like HKS.

Rx7Roadster

iTrader: (1)

RB Header to RB Presilencer to HKS 50 mm catback. They still have it at Mazdatrix. Same exhaust as me except that I have a Bonez Hi Flo cat. Its a good exhaust. I really like it.

Rxmfn7

iTrader: (4)

The header and presilencer definately look to be racing beat. (www.racingbeat.com) Good stuff..


As for the cat-back, it does look like an HKS system, although maybe a little older than this one.

(found at www.mazdatrix.com)

As for the emissions issue, you are correct in that there is no cat, thats a pre-silencer. You car should be able to pass fine with a high-flow cat, mine passed with flying colors. Unfortunately, there is no cat that you can buy that comes with flanges to fit between the header and the cat-back. What I did is buy a good high-flow cat (www.rx7.com and look for the Bonez cat. Rotary engines need special cats that will hold up to the high heat and exhaust pulses a rotary produces. Cheaper "universal" cats will burn up in no time) and then weld extention flanges onto it, however long the presilencer is. ( I believe its around 18" if I recall..) Nice car

ddub

thx for the kind words

my plans are to get the bonez high-flow cat like you suggested, get 2 apexi n1 mufflers and go to a muffler shop where they can weld all of that in for me with 2.5 inch piping...then ill just get rid of the mufflers, pre-silencer and such.

thanks for the help and suggestions everyone

ddub

hmm the bonez cat is expensive =/ does the rx7 really need a special kind of cat? cuz there are magnaflow high-flow cats on ebay for 60-70 bucks

SonicRaT

iTrader: (6)

It'll kill any normal cheap cat, they run too hot.

ProjectRESuperG

Hmm...two N1s? It will be LOUD! Good luck!

From the tips it does look like HKS cat back, and RB pre, and dp. Should be a good setup for not being overly loud. The N1 will definitely be louder.

gray 87 fc

listen man its is rracing beat header and presilencers with hks exhauist but if you are going to go apex-i go with the single n1 tip a single tip makes more power than the dual i have a rb header a ps with the apex-i n1 single tip and you can tell the difference

in2psi

It looks like a dynomax exhaust! Like the one that is on my car!

Sir Rupert Hobo

ddub... i had the EXACT same setup on my 88 gxl. and it was HELLA loud. i recently removed the P.S. with just the main cat. it's toned down a hair. and i am also putting my RB catback on this week. that should definetly quiet things down.

about the catback. is it the HKS or dynomax? my mufflers look kida grimmy and sooty. they look to be about 3-6 years old. which ones are they? they look like ddub's...

also any pics of the dynomax?

abarlas

You could sell the presilencer. Check out the for sale section on this forum.

wozzoom

Any pics from under the hood?

Also, if you keep the Racing Beat header and Pre-silencer and add the Apexi N-1 mufflers, you might loose operation of your 6-ports.

The 86-88 Non turbos engines use exhaust back presure to operate 2 aux ports on the intake. Without enough back presure, the ports don't open and you loose power from 3800 RPM up.

As for catalytic converters? The Bonez pipe from rx7.com is expensive and has to be cut to be installed with your setup. Another alternative is a Random Technology Cat. Random and the Bonez are the only two cats on the market that are rotary approved.

ddub

well im not keeping the presilencer, what if i ran the RB header to a bonez high-flow cat to apexi n1 duals? would i lose operation still?

=/ i dont know a whole lot about rx7's yet so im trying to figure out the best setup i can go to (excluding true duals) so any help/suggestions is welcomed

Rxmfn7

iTrader: (4)

With a cat or pre-silencer, there should still be sufficient pressure to open the auxillary ports. Im running a RB header into a bonez H-F cat, then Greddy cat-back, and my ports open fine. N1s will be loud, even with the cat, just letting you know....

wozzoom

The bonez cat will provide enough back presure. The N1 duals will be loud like others have said, but you'll be fine with back presure.

Center of The Universe

Is that TII LSD?

Center of The Universe

Oh BTW. Awsome car

(GOD THE S4 Mirrors! They look so much better than the S5!)

Rx7Roadster

iTrader: (1)

Yes that is the HKS exhaust that Rxmfn7 pictured. I have the same exact one and it look just like it.The N1 wont provide much gain over that exhaust that you have. It is definetly not worth the money you will spend. Also 2.5" piping for a dual NA system is too large. The 2" pipes on the HKS exhaust are plenty big for a stock port. If I were you I would keep the catback. It is fairly expensive and I think that it preforms well.