on any rx7 what is better single or dual exhaust??? on alll my cars i got better performance from single for some reason dual exhaust made my car slower...please i would like to know everybody thinks...

 

Non turbo??? With or without emissions???

True duals on a non turbo is the best (a single pipe all the way back for each rotor)

 

Here's the deal on single or dual..

Its got to do with flow versus weight versus noise.....

you can get a much lighter, high flowing single exhaust.. at the expense of noise...... Using a single exhaust branched to dual cans you can get the same flow rate, with less noise, at the expense of weight (and cost of materials)

True Duals are best on an N/A... HOWEVER.. not on an otherwise stock car... you need to have some fuel control to get the most out of a true dual system (no emissions) because stock N/A's go pig rich when you unplug the exhasut (on s4's.. you also run into problems with getting the 6-ports to open.. which also dogs 'em out)

Running trus duals with two cats is a retarded proposition... don't waste your time!!!

It also depends on what exhaust systems you were using, do you have an S4?? Was there enough backpressure with the duals to open the 6-ports, or were the duals stock versus an aftermarket single???? I mean... there are a Myriad of things that could cause the car to run slower with duals than the single exhaust...

 

So an S4 still has 6 ports? Someone told me that they only have 4.
Is backpressure important with a rotary?

I installed a free flowing exhaust (straight through w/o cat) and it reduced the low end torque, but the top end HP benefitted. This is a piston engine though so I don't know how a rotary would react. I assume the flow dynamics in the combustion chamber are different.

 

True dual nets the most power on an N/A but is pretty damned loud. S4's have 5-6th port, S5's do not as well as Turbo II's. Figure actually a drop of about 20 lbs if you go with a dual aftermarket system wihout cats.

 

Are you trying to claim that S5 N/A cars do not have auxillary ports?

 

on my 87 non turbo without emissions at all.. racing beat header 4.10 possie rear exhuast port stock computer my car ran a 13.20 with dual exhaust and fresh rebuild with apexi ni mufflers. after a few people telling me that single was better i switched to a 2 1\2 straight trough no cats just one apexi n1 muffler it was louder than you could belive but the pay was great it droped my times down to 12.90 at 118 mph so in my eyes it was much better with single plus my top end was nuts...the only down fall was tickets lol lol... and also i took as much wait of the car as i could

 

Ah, put down the crack pipe.

All 13B non turbos since '84 have aux ports. That would be 1984-2006

Regardless of what series.

Only the factory Turbos do not have aux ports

 

This is not on a stock port system or this is with nitrous???

Otherwise I am calling a big BS.

And Mazda's do not have "pozzie rear"s . Pozi or Pozitraction is GM's name for a Limited Slip Differential (LSD), and since there are not stock GM parts on a RX-7... well...then there is no Pozi rear end on a RX-7.

And calling a Limited Slip Differential (LSD) a Pozi, is like calling all refrigerators Kenmores.

Call it by what it is, not some brand name.

 

12.90 @ 118 huh? Let's see your mods and the timeslip.

 

ya really, i want to bulid a 12 sec. NA rx7....

 

hahaha 118.

 

Single is the better choice if you're looking to remove weight, but if you don't mind having a system that almost weighs as much as the stocker, true duals are a good bet, they sound really unique and aren't THAT loud. The video on the Mazdatrix site is of a car with a big port and the exhaust diffusers removed, so you can't say that THAT'S how every car will sound with that system on it.

 

ok!!!!! you guys cant be for real you mean to tell me nobody here has built a rx7 to run high 12.90 low 13.20 with out nittros or turbo give it a break because here in the bronx we do it all the time... see the differnce is you guys must go by the book we dont go by the book.. you act like 12.90 is fast for an rx7 are you kidding me or what you dont always need turbo or nittros to go fast.. no need to dabait it your wright lol lol lol you guys should be driving a ford or camro sound like more you speed there the only cars that can break 12.90 or 13sec lol give it a break
O AND YOUR RIGHT IT WAS NOT POSSIE IT WAS LSD!!!!!!!!!!!!!!!!!!!!!!! ALL I KNOW MY CAR BOTH TIRES ALWAYS SPUN NO MATTER WHAT 360 180 SIDE WAYS STAND STILL DUMPING THE CLUTCH AT 8000 FOWARD REVERSE YOU NAME IT

 

YES IT WAS EXHUAST PORTED THAT IS WHAT I MENT TO SAY

 

 

Did you go to grammar school?

 

Is it peripheral ported or something? Otherwise I dont think you can make the power needed for those times with an NA engine.
Or are you talking 1/8 mile times, because I could believe that.

 

BRAND NEW HOUSINGS BRAND NEW INTERMEDITA PLATES 85 GLS SE ROTORS 94 CORNER SPRINGS AND SIDE SEALS 2 PEACE APEX SEALS 2MM ALSO IT WAS A FRESH REBUILT MOTOR... AN 83 TRANNY 4 PUCK ACT CLUTCH WALBRO FUEL PUMP WITH AN 327 TURBO 2 COMPUTER.. NO SMOG WHAT SO EVER EVERYTHING WAS OFF THE MOTOR.. IT WAS A 4 LUG NOT FIVE LUG SO IT WAS LITER. M.A.F WAS WORKED ON BY SHORTY MAZDA FOR MAX INRICHMENT RACING BEAT HEADER APEXI N1 JACOBS IGNITION APEXI SAFC CONTROL

 

WOW, the more you post the more ignorant you sound and the less believable your claims. Not to mention the dialect YO.



Its ENRICHMENT, and running pig rich ("MAX INRICHMENT") will decrease power, not make more.

Also, running the 85 GSL SE rotors will DECREASE power over 86-88 and make even less then the higher compression and lighter 89-91 rotors.

AND GSL SE ROTORS USE 3mm APEX SEALS FOOL, NOT 2MM. So your “94 corner seals and 2mm 2 piece apex seals" would NOT work.

Stop with the buzz words and if your going to bullshit us, at least learn a little more before you try to fool us as to you knowing what the hell your talking about.

I called your BS, and your busted!


~Mike............

 

12.9 must be the 0-60 time.

 

12.9 @ 118....wow, must have been taking off on ice too.... 1/2 second and 16mph faster than mine.

 

I thought trolls mostly bred on Honda forums cos it is blatant thats what this guy is.

RockLobster: you have an awesome username.

 

The N327 is a non turbo computer for a 87.5-88 non turbo 13B.

The N327 already runs way way rich, so if the AFM was tinkered to further enrich would mean that you are turning the SAFC way way way down.

I still am calling BS. To many of your things don't add up.

you should have just said nitrous... I might have belived that.

remember 1/4 mile times are on a track, not using your G-force plug in dash/windsheild mounted box.

 

damn if I knew I could have put that little bit of work and money into my N/A and got into the 12's I wouldnt have sold it and dumped a **** load of money into buying a TII, engine rebuild/porting, 3"exhaust, bigger fuel injector and FMIC to only get in the 13's!!!!!! IM SO STUPID!!!!!!
LOL LOL LOL LOL LOL LOL LOL LOL