pp13bnos

iTrader: (1)

Tonight, i decided to go ahead and put mandrel bent, dual, 2" exaust all the way out. I'm shure you guys remember me saying i was going to put on 2 RB pre-silencers, and then into the RB mubblers. Also that means no collecter. After working on it for 4hrs, because we don't have a lift, and i'm crawling around on my stomache, the car is finished. Over all the car revs faster. Not by to much but like going from a stock flywheel, to a lightend steel flywheel. To be honest the hp gains where'nt as big as i was expecting. Maybe 5-10hp according to the butt dyno. But at idle it's still pretty quite, as with light driving. But once under hard acceration, it sounds realy good. Like a rotary should.

Now i've noticed what feels like a miss under hard acceleration...almost like the coil is starting to die or something. Tomorow, i'm going pull the plugs, and check em out, and then swap in a used leading coil i have laying around.

Quick question. The air pump, needs no back pressure from the exaust, to work correctly correct? The reason i ask this is, because with my old exaust, i felt a very sudden blast of power around 5.5k. Now it seems as it almost has disappeard. Tell me what you guys think. Later, CJ

No7Yet

Very nice. The true-dual exhaust on a rotary sounds really good - sort of a stereo effect Enjoy it. Your miss is probably bad plugs - plugs can work wonders on RXes. Try that first.

Without getting into a backpressure=bad, flow velocity=good discussion, no, your airpump operates soleley from engine power. You're probably thinking of the 6PI on the S4s that require backpressure to open. Both your VDI and 6PI are operated from airpump pressure. Now you should start thinking about removing the airpump, though, since it's not really doing anything

The 5.5k kick is the VDI opening. The reason you don't feel it as much any more is because your engine isn't starving for air just before it does . Basically, your engine has a smoother torque curve, which is a good thing. That's why your butt dyno measurements are probably inaccurate - there's lots more power, but it's much smoother now, so it's "harder" to detect gains. Dyno that bad boy and be impressed.

Brandon

The Ace

Hey, I wanna butt-dyno my TII with a full exhaust too....

of course I'll have to BUY the full exhaust first

SpeedRacer

I have the racing beat dual outlet headers(uncollected) but haven't put them on yet cause I don't have the money to get custome piping welded on yet, and I want to get mufflers and presilencers first. However, I did have an extra set of collected headers lying around the garage, and I was replacing my exhaust manifold to engine gasket, so I figured I'd throw it on to see what happens. I had a bonez racepipe on previously, so I had to take that off, as these headers connect to the stock CAT location. I gutted my cat and installed the headers and gutted cat. First impressions, LOUD as HELL. I think the gutted cat is a lot louder, than if I had a presilencer on. The sound is very nasty chainsaw-ish. I think part of the nasty sound is an exhaust leak. The headers were a TAD to short I think, so I may try using two gaskets or something where the headers connect to the CAT and see if that helps. Also, a gutted cat is NOT as straight through as I would have thought. There are metal ribs that line the inside of the cat, and a metal tube that goes right through the middle of it, where fresh air used to come in from the SAP. Anyways, seat of the pants dyno, I didn't feel any difference, but after driving it for a few days, I think my car is quite a bit faster. It just doesn't feel that way, but every time accelerate hard and look at the speedo, I am surpised at how fast I got to whatever speed. My 6-ports and VDI are wired open so the torque curve is very smooth. Also my hesitation problem went away after putting on my headers, although I don't know if the headers solved the problem. It may have been the exhaust leak sending weird signals to the O2 sensor or something, as the leak was before the O2 sensor. Also I took out all my fuel injectors and soaked them in degreaser for 8 hours, so that might have helped also. Anyways, I'll have to race my brothers Integra GS-R to see how much power I've gained. I use his car as a constant to see how my mods affect my car, as his car is stock and we are always a CLOSE race.

pp13bnos

iTrader: (1)

Today, i swaped out the coil. No more missing on hard accel. But for good measure, i put in some plugs after that. Runs better than ever. Now i just need to find the exaust leak, and i'll be happy with the car for a week or two. After that, its time for a HI-6. CJ

Turbo FB.

I heard that thing sounds like a Boinger












Later..

pp13bnos

iTrader: (1)

Hey.....those are fightn' words!

CJ

mazdaspeed7

It sounds like somebody wants to rumble.....

Seriously though...there is no way that exhaust sounds like a boinger. Its a sound only a rotary with true dual exhaust can make. And it sounds awesome.

What do you think of it CJ? I was pretty happy with mine. Took a little while to get used to the part throttle noise, but other than that, its great.

pp13bnos

iTrader: (1)

TurboFB is a buddy of mine, in rpnw. Hes just giving me crap. This in my opinion, is awesome sounding. Nice aggresive idle. Not rice boy, or angry chainsaw on steroids, but something smooth yet semi aggresive. Its still pretty quite on part throttle, but under full throttle is shure is smooth. I would'nt go back. Infact, if i would of know what it would of sounded like, i would have did it when i first put the engine in. Sounds great! CJ

JDM13B

what kinda of mufflers do u guys got, because i just put true dual on my 89 gxl with 2 big apex n1's and it sounds like a harley out of hell. unbearably loud...i bought some hks hipers and im choppin off the n1's tomorrow to put the hks ones on...hope they make a difference