Hey,

I'm buying a cat-back for my '93 RX-7 soon. I want something with a fairly small tip. Two tips is preferable, actually. None of thos 5" Greddy deals. Does anyone have suggestions on which system to buy, as well as where to buy it?

Also, which is the best downpipe on the market for these cars?

Thanks,
Clint Fralick

 

you'd probably like the Racing Beat dual tip. i've got it now. it'd probably be kinda quiet with the stock cat, though its not with a hi flow...

 

Perform a search for "i8urchvy" He has a Pettit Dual Tip Cat-back for sale

 

Hate to break it to you, but you are going to have a big tip. It has to be to let it flow.

I love the look of the apexi N1 single just because it slopes with body and sounds great too.

 

If you want performance then you need bigger tip. I just got done installing my hi flow cat and apexi N1 cat back. I looks great, flows well with the body and is tucked under there really nicely. Also it sounds good. It would be quieter with the stock cat but it is really not all that loud. If I roll up the windows then I can only hear the drone when down shifting. It is awesome!

 

Racing Beat Dual Tip - Available in black painted w polished tips or fully polished 3in inlet w/ dual 3.5" (3"id) tips Looks & sounds Great and plenty of flow for good perf. the M2 SS Down pipe is one of the best if not the best. when Installing the DP get it ThermoTec wrapped - Makes a Huge reduction in the amount of heat radiated into the engine compartment!

 

I don't think anyone was thinking of a single 2" tip. Why would you need > single 3" tip for performance? Adding a 4" tip to a straight through 3" system just doesn't seem to me like it would do anything (other than look big) and I don't think it would do anything for a systems with added restrictions (cat, muffler) either.

The RB duel-tip CB is very nice. Has two 3" tips that look very close to stock. It's a bit more restrictive than some of the really open systems, but that has nothing to do with the tip size.

 

no, that is incorrect. That logicv may be true for liquids, but not for gases. For gases, after a restriction (muffler) the exit side must be larger than the inlet in order not to restrict air flow. the gases moves more slowly after, adn it needs larger diamter to let it out.

that is why 3" exhaust haev like 4" tips.

 

And why the Racing Beat muffler has twin tips. Two 2.5" pipes have significantly more area than a single 3" pipe.

 

Racing Beat does not make the painted dual tip anymore. I was going to get that but they said that they discontinued that one and all they have is the polished which I really did not want. Then I decided just to go for more performance.

 

Thanks for the replies. What do you people think of the Apex'i N1 Dual Exhaust system. I really like the look of the dual canister set-up. How does it flow compared to some of the other popular cat-backs?

Clint Fralick

 

the apexi n1 dual is a very nice looking exhaust and the flow is really good. there is a drawback...the sound. it is the loudest dang thing i have ever heard in my life!

 

I just got my RB Dual tip Painted SS in June 2001 - They changed them slightly awhile ago (bigger tips w/empossed RB logo) and mine is the newer style. think it may flow a littler better also.

 

They changed and got rid of the painted dual tip. I tried to get mine a couple of months ago and after ordering it I waited about 1.5 months and they had not even started working on them and that's when I decided to go with the apexi.

 

Does the Apex'i N1 dual canister use all the stock mounting points? Will it bolt straight up to my stock cat? I won't have the money for a high-flow cat for a while so this is sort of important.
Thanks

Clint Fralick

 

And the worst sounding. You also forgot the extra weight. A good portion of the exhaust is twin 3" piping before the mufflers, for a lot of unnecessary weight. The negligible gain you might get over another muffler is offset by the weight and noise.

I've never heard another exhaust on an RX-7 that I liked less. One of my old friends has one and it sounds like crap. It's an embarassment. Of course he thinks it's great...

 

I was thinking of the RB dual tip too, but I don't like loud exhaust notes.....I prefer just hearing the turbos spool..ITs kinda like a stealth hi-tec sounding thing. Thats why I put the stock cat-back back on. I have an HKS lying around, but I don't know which one. Anyone know the type and specs? Its dual tip, but double layered as well....there is a little perforated spacer between the two layers. and how loud is the RB compared to stock?

 

Apexi N1 single even looks better than dual in my opinion, the single looks much for racey (if that is a word)

 

if you want to look and sound gay, get a cannister exhaust system from either Apex or HKS. all of them come with 5"+ tips, and they seriously sound like ****. i swear i have heard civics that sound nicer than then FD with either an N1 Single, N1 Dual, Apex GT Spec, GReddy PE, or an HKS (forgot the model name. the one with the huge fartcan).

if you want, i can dig up videos of FD's with similar types of exhaust sytems and youll see just how gay they sound. i couldn't believe my ears!

on the other hand, RB or M2 dual tips sound and look more classy. with double walled, dual, polished 3" tips...they look the best. (unlike the single walled 5"+ tips that will rust and look even shittier, if thats possible). also, the power differences are marginal. im guessing you will get no more than 5 extra horsepower with a fartcan, than with a nice RB or M2 dual tip.

do you really want to be looked at as a ricer with a fartcan?

 

Hard to say, since the best comparison I can give was with both on my non-sequential car, with a Tri-Point downpipe and a Tri-Point midpipe with a Borla XR-1 in the middle to try to knock the noise level down.

Both are quiet and very well behaved at idle and cruising around town. Both can be good and loud at WOT. With the stock cat-back on the car, a stock IC, and a blown engine (both rotors), I dyno'd 238 RWHP @ 10 psi, which I thought was pretty good. Everyone was backing away from the dyno and leaving the building though, so even a stock cat-back can get loud when you open up the exhaust and especially with both turbos operating.

The point is, neither the stock cat-back nor the RB twin tip are loud when they shouldn't be. If you're WOT, that's one thing, but my friends with PFS 4" single tips and A'pex N1 duals can be heard LONG before they show up at my place, even through the walls and intervening houses. I don't even need my doorbell to know that an RX-7 just arrived.

 

LOL. Thanks for the reply Jim. I guess the RB dual tip is definetly louder than stock though...

 

it doesn't that that deep my friend has it on a MR2....

 

The differences are minor, though. Lots of people complain that the RB is too quiet. In most cases, the RB will be only slightly louder than stock. The real Db difference is when you're at full throttle at high rpm with both turbos going.

If you just want to hear the turbos going, simply replace the precat with a good downpipe(can't go wrong with M2's SS DP).

 

I have that same exhaust sitting in my garage. It came with the car. I could never find out which model it was. It was looking pretty old so I replaced it.

 

I'll post a pict. tomorrow...it was pretty loud, with low rumble...