von

My friend dynoes his N/A 87 I think with bolt ons , ported manifold , full ignition. He dynoed his exaust with those mods and got 25 flywheel horspower....The filter should give 5fhp with full exaust.

von

He had a custom setup with glasspacks at the end. Dont know about you but 25hp is awsome. I have a streight pipe after my stock manifold and I am willing to bet that I gained 15hp. That is an awsome hp/Doller mod. Bonez race pipe only 150 and catback custom 250.

Chris Ng

People can keep quoteing huge power increases with exhausts.. The problem is all the proof and information you are getting from these people only include information on the end results of their testing... They dynoed a car at 100HP, they added their exhaust and saw 133HP, 33% increase.. Big friggen deal.. unless they removed their current exhaust and installed a brand new stock system to compare their results, how the hell is it reasonable to assume every car will experience the same type of gains... Perhaps they should include a disclaimer that states "33% increase in power when replacing old worn out, clogged stock exhaust systems"
Most people who have replaced their exhaust systems and noticed a gain have noticed it because the exhaust they were replacing was already to the point of restricting horsepower..

If you guys want to continue beliving that you will achieve 30% power increases by just adding an exhaust, without taking into concideration the current tune of your vehicle, then you must also stop bashing honda owners who add intakes, exhaust, cold airboxes and start spouting off that they have 200+ hp in boltons..

BlackRx7

my MPH on that 16.76 was 85

on that 16.3 run I ran at 83

I'm not sum dumb **** I know how to drive a car, slip the clutch a little at launch and I never lifted the gas pedal during shifts, I was getting a nice chirp in second

Maxthe7man

Take your average FC to a drag strip and watch it run an 18+ quarter mile...
Once I learned how to get the g-tech readings right, I realized it wasn't lying to me, there is a member on this forum who prior to upgrades posted a '38' hp on the g-tech, I am sure to avoid ridicule he won't admit to it, but yes his car shows 38, with upgrades it now shows about 85 rwhp... I use to beleive the g-tech was a load of bunk, however in my truck I've hit alot of 470-480 hp readings, which is right in the ballpark it dyno'd at the wheels, so take your no it can't be attitude and stick it right up your ***..
Last weekend a bunch of us watched a GTU with a hundred shot of nos run 18's at 65 mph.. Take a look at the dyno sheets of the N/a guys on the forum who did every upgrade to the car possible and never broke 150 hp if they even got that close.., your average bone stock FC does not make a whole lot of hp, my GM van was faster than my FC when If first got it, like it or not they are slow..Max

Maxthe7man

Oh yeah one more thing on that GTU, what.. 2800 lb car? 18 second quarter mile= 62 rwhp... woooo....
Mr. rx-7 TT this fingers for you....Max

Josepi

I have a dyno of my TII...while it was running perfect. Boosting fine at stock levels. Hell, even the stock airbox and generic air filter. Once I get an exhuast i'll slap it on a dyno (the same one I used before) and get a scanned copy. Anyone want to give me a full exhaust?

Josepi

As far as the G-Tech goes. Don't use that POS to guage HP. You can gain HP by rolling your windows up and changing tire pressure. WTF?!! Put some 17's on and watch it say you lost HP. A dyno is the only way...

AbecX

Finally some people with insight posting up about corporate america and their marketing ploy's.

How much does a 2nd gen n/a weigh in full trim stock anyway? 100rwhp doesnt seem like a whole lot to push it down the track to a low 16 stock unless it weighs like 2600#'s

AbecX

You mean nitrous? I call moron on you, too.

banzaitoyota

MAXTHE7MAN, Have you EVER taken your G-TECH (in my opinion Rice-Tech) and done a dyno run and compared the numbers?

The Ace

Behold an individual of -very- low intelligence. Speaks without knowing all the facts...



....what was that ? what are you saying grandpa ? "Better stay silent and look like a fool than speak and prove you ARE a fool ?"......hhmmmm, have to think about it....

AbecX

I'm sorry but anyone who says NAWS now-a-days just reminds me of the queers in the fast and the furious

" You still owe me a 9 second car "

tims

like I said before I don't doubt the dyno results. And in my years of racing rotary engined cars the best place to find "hidden" power is by experimenting with the exhaust system. every dyno run I have done has resulted in more power. We build our own systems and have modified some RB headers and have built our own header. each system has produced different results. we also built two or three intake manifolds and the results were nowhere near as dramatic as the exhuast. several other friends and competitors have relayed the same information to us. the big gains in HP on rotary engines ported or not are found in the design of the exhaust. dual mufflers seem to work well, short headers work well, single muffler with short exit works. there is alot to be gained from the OEM system and I would bet that 28% is easily attainable. it maybe at an elevated RPM say over 6000rpm but it should still be easy to do. now would I pay $1400 for this system, no. But I have seem systems built by muffler shops and race prep shops that look very similair. I would not doubt the numbers but I also don't think it is going to be a dramatic effect on a street car. except that it will be louder and all the smog equipment will be removed.

The Ace

As far as I can tell he didnt say "NAWS", he said "NOS", which is one of the companies that produce and sell N2O systems for cars. If you want to get nitty-picky, the correct term would be "nitrous oxide", but this is hardly a good seller term

Also, there is nothing wrong with N2O systems. People have been using them for decades, either on the road or in the track. Judging a product just from a single -badly misinformed- movie is just bad form

And indeed a guy that wants to lie would not go as far as stating
He would have said something like "yeah I know my ****, I've been working on rotaries, like, forever, yo"

Know thyself, and know thy facts (I'm greek, cannt you tell ? )

AbecX

I never said nitrous was bad, hell a 125 shot wakes up just about any car Just people that say NAWS around here in dallas area are opening themselves up to getting flamed.

The Ace

And to get back on track: from my own personal experience, I saw a 30RWHP (well, 27RWHP actually, but who'll notice ?) in my '92 TII with just a K&N filter and a 2,5" dual catback with free-flowing mufflers (custom made). For a total of 175EUR, this is a mod you cannt beat

And I will state again that both my cats are intact (pre- and main), and these are the biggest restriction in the exhaust system. Removing the pre-cat is a sure-proof way to increase boost by at least 2psi (meaning at least a 15% increase in RWHP), and the main cat (although illegal all around the world) will provide almost the same increase.

I cannt speak for the NAs or the removal of the cats, but if a simple catback gave me almost 20%, then 28% from a full exhaust is almost guaranteed on a TII, and VERY likely on an NA...

AbecX

You do realize exhaust plays a HUGE part on a turbo powered car? I've seen cars that GAIN lots of power going to 3 and 4 inch exhaust tubing. You put that on anyother car thats not pushing out 400+ hp its going to make it dog slow. Turbo and N/A engine are two totally different ball games.

pearlwing

I think youre gay and have nothing better to do in life than flaming people. Start with getting a life or you'll end up working in a kindergarden playing with lil boys.

Bill Harrison

Guys, its all speculation till you try it yourselves. I personally have, and have drag raced my car MANY MANY times. Before and after almost all my mods. Car ran high 16's low 17's stock. That was with old worn out exhaust. I installed a stock good exhaust, full tune up, and the number dropped to 16.1-16.2. This was in a superlight car ALL BASE, only options were ac and power mirrors. I then installed Headers, which replaced both front cats, a custom main cat replacement pipe, and a full exhaust. And lo and behold, I went a massive 15.9-16.0. And no, dont tell me I dont know how to drive. I have drag raced HUNDREDS of times. I was racing this car in 95, when I was the ONLY import that raced there, and hondas were sane cars for economy commuting (which by the way is what they still should be ) Just for reference, the exact same car with a TII swap stock but for the cat replacement and Borla exhaust went 14.10.

Lets just say, I beleive a 10-15 horse increase is something realistic. I think a 28% claim IS unrealistic. Bash me all you like, but I KNOW these cars inside out. How many here have rebuilt a rotary? Done a TII swap? Rebuilt the tranny? Dissassembled and rebuilt an entire car? Put together a supercharged 88?

Not many of you. So unless you have some REAL experience with these cars, please do not try to argue with the guys that do. I am sick of seeing all this "it definitely feels" and "comparitively" being used as a track and dyno! Unless you have before and after numbers you have NOTHING!

dre_2ooo

Um..... NOS is a brand name of nitrious-oxide (N2O).

I gues you'd be a moron for calling your mustang a "ford."

Remember everyone, if this guy irritates you, he looks like this : you can ALWAYS laugh at him.

Also, he claims he is an expert at linux/unix as well as sEVERAL other OS's and HTML. I doubt he even owns a MUSTANG (or any other car) to begin with, lol.

stinkfist

Since you have been doing this much longer than me, show me some of the dyno sheets of motors you have built.

As a matter of fact ANYBODY show me a dyno sheet of a STOCK car makeing 28% increase in power with just exhaust. This thread has been going on for a while now and not 1 person has found a dyno sheet to prove this.

I have spent A LOT of time on the dyno with several different cars. I crew cheif for a front running IT7 car. We dyno tune often.

Until I see dyno sheets the post above is BULL ****! Along with any other claim in this thread that claims 28% increase in WHP.

And you people claiming these gains on your turbo cars, no ****, it's a turbo.

I know exhaust makes a big difference. It's not some rotary secret. it's true for any engine.

Anybody who has not done any dyno tuning or even put an aftermarket exhaust on your car should get out of this thread now.

You people are funny as hell. You sound like a bunch of honda kids.

I'm going to go into buisness and make exhaust tips that add 50% more hp. I will sell them for $159.99.
I'm takeing orders now.

Mike

dre_2ooo

UM... if you have been reading.... there is a dyno sheet posted. sheesh.

SonicRaT

iTrader: (6)

Dre: what does his abilities with operating systems have to do with what car he owns?

AbecX: You still lack any understanding of a rotary engine as I explained earlier, until you do, don't go around saying an exhaust upgrade won't help any, because you obviously don't know

pearlwing: You say all he has to do in life is flame, and that he is gay? What are you doing right there?

Maxthe7man: If you're so stuck on G-tech's and saying FC's are slow and can't run any better than 18's stock, I'll have you know my 'bone' stock 87NA ran a 16.3 on that thing, and that had 132K miles on it and was sitting for 6 months.

rx7_ragtop

I have first-hand dyno experience. I picked up ~20 rwhp with just a single 3" exhaust WITH a cat, and a cone filter. Also ~1 full second in the 1/8. I DON't have a before dyno of MY car, but I do have a dyno of another car the same day, bone stock, in perfect condition, same year. They got 110 RWHP and I got 130. I have the timeslips (somewhere) showing my drop in 1/8 mile time and increase in MPH. This is on a 125K+ mile motor.

Brad