Hey,
Just wondering if this is normal....

I just got my RB presilencer hooked up to my 87' base last night, and tried revving hard this morning after I got to work, and my cousin didn't see anything out the exhaust except extra fuel..

Is that normal for this setup?
Rebuilt engine as of aug. 07, RB collected header, RB presilencer, stock Y-pipe, stockish style generic mufflers. [the y-pipe and the mufflers aren't new by any means], on the intake side.. I have the snorkel still in place, but replaced the airbox with a cone filter.

My friend just bought an 88' vert, and we put a Borla catback, RB presilencer, and RB precat replacement pipe on [stock exhaust manifold, stock airbox] and it shoots fire.

Is this normal? Perhaps I'm running leaner than normal?

lol.. I'm not too worried about not shooting flames, but mostly curious..

 

Stock mufflers, the Borla's are almost straight through. Just means you havent gotten them hot enough and pop'ed em.

 

Yeah, that Y pipe and stock mufflers are killing your Flame On. The Y pipe is teensy tiney inside, and the mufflers alone will kill the flame poofs. Run a single catback with a high flow muffler and you will definitely get flames, crap, even a aftermarket Y and decent mufflers ( paired with a header and straight pipe ) will render flame-age. Are you trying to set your bumper on fire? thats always fun too. : )

 

Marc>> Popped em?

endneu913>> I didn't know the Y-pipe was significantly smaller.
Your comment combined with Marc's about the Borlas makes more sense.

I'd consider a single catback, but I love symmetry too much ^_-

and lol, no I don't want to burn the rear bumper..

as a side note, I've been watching for a cheap RB catback.. Nothing yet.. That'd probably do it, huh?
Do you guys think that would sound better than this? or just be louder?

 

OMG, yeah its disgusting, i cant post a number, but my guess is the i.d. is 1.75" at the smallest part....

I agree about symmetry, I will always have a dual, and since my Bomex rear bumper is a double, im kinda stuck too

Keep your eyes peeled, if a RB system does come up, it will go fast. I don't think it will be LOUDer... but it will be a lot deeper and rumbly, less tinny high noises as some cheaper exhaust components. RB uses thicker steel which keeps the high pitch tin can sounds down, and their muffler itself is designed to have high flow AND good noise suppression the air enter the bottom and leaves at the top iirc. If you've ever heard a RB true Dual, you will know what i mean.. Its almost all straight through, but sounds near-stock in low rpms and pretty nice and mellow in the higher range. Erikseven has one on one of his cars.. i likey!

I would place your desires for exhaust in this order:
1- Air flow design
close #2- sound
3..... flame shooting abilities... LOL

 

Popped em = backfire

The RB cat-back will be louder but with the presilencer it shouldn't be bad. As for sounding better than a Borla? I am not sure cuz I have not heard a Borla exh on an rx7.

Im running a RB header and RB cat-back with presilencer & cat removed. It sounds really good, a touch louder than what I wanted, but its not obnoxiously loud

 

^_^' I don't know too much about exhausts[though I'm sure this was pretty obvious] so bear with me.. 1.75" stock to 2.5" RB is a big difference? .75" Hmm.... I guess it would be since .75"/1.75" = 42.8%

So, the stock ID will slow down the exhaust, in this case, helping to prevent the flame from reaching the end?

hehe, good to hear someone else who likes the symmetry. I don't think I've heard a True Dual system yet.. Though I'd love to get one if I had extra $ laying around for it.. Power, sound, symmetry.. What's not to want?

Uh oh, I've been caught.. I haven't really had a plan, just kinda doing things that I know should improve it. [Before the presilencer I had the header installed, before that I switched to a better stock Y-pipe and mufflers, and finally before that I switched to a new, single cat]

So, if I can find an RB catback.. I'll have coincidentally fulfilled all 3 of your points there ?

Squeeb >> Ok, I was kinda confused because I can hear it backfiring louder than before [oops.. forgot to mention this.. ^_^"], but I couldn't see any flames.
No regrets on that setup? [other than the slightly too loud part] It seems to be exactly what I'm trying to get together..

The Borla sounded good, but it may be a bit on the loud side [I was riding along for the first test drive with it] I think I recall it being a bit too loud at idle [or I am not remembering it right..]

 

No regrets at all, I love it. Idle sound is perfect, it can be annoying on long roads trips but music drowns out the noise np. Have yet to be pulled over for it but i'm always careful around cops /knock on wood