You would be correct sir and thank you for knowing what you're talking about.
jjwalker, you need to do some reading yourself apparently and get off the fake *** Wiki pages. In an NA car, no bigger than 2.5" would be correct and depending on your goals would want either a short or long primary exhaust to help with the scavenging of exhaust gasses. Turbo cars don't apply to this. The best exhaust for a turbo car is, as stated, no exhaust. I've played around with NA's long enough to know what is right for them

 

I have also found that all things considered a single 2.5" seems to be the best for N/A Cars, with a good header.

 

Yep. The FB's love the long primary, so a well designed uncollected header, with twin 1 7/8"- 2" pipes all the way back then collect to a 2 1/2" just before the rear axle.

 

Ok, so one more question. Can anyone recommend an FCD that clamps voltage? Will a knights sport FCD cause any lean mix issues?

 

Another question. Do I need to spend 250$ on a Bonez cat? Or will a regular universal cat with an airpipe work?

 

Any takers?

 

I have a Racing Beat FCD that works great if you are interested... It on my for sale thread.

 

I told you I have an FCD for sale too.

 

12A, I need the FCD for an S5.

Incubus - I would like to buy your FCD, but I still need to verify it clamps voltage, and doesn't just use a resistor type driver. You said it was knightsport? Does anyone know if Knightsport uses clamping voltage?

 

BAMATO.

IF your trying to be cheap and simple. I would recommend the SSAC exhaust for turboII's
Its about 250-275 shipped
THe only bad part about it is that the resonator is 2 1/2. IT is very light and very tight under the car. I have coil overs and my exhaust has never scraped.

MY mods.
COne filter, 720cc x2, fcd, SSAC exhaust, S5 engine in 88TII

FCD is a must. I would almost want to say 720cc secondaries are a must also.
I say that because with my basic mods im seeing up to 12 psi on cool night in 3rd and 4th gears. GL

 

Not necessarily trying to be cheap and simple.... I just enjoy the idea of building my exhaust. Yes I have mentioned I don't want the most expensive stuff, but I don't want to be cutting corners either. I don't want to spend a few hundred dollars or more on a system that I'll end up hacking apart to make emissions legal, or to sound the way I want it.

I will be buying an FCD, no question about that. As for the secondaries, I'll have to see how my boost levels come out to know what route I'll end up taking.

 

don't worry about emissions i can take care of that for ya

 

Alright, new shopping list:

Corksport 3" downpipe (ordered)
Innovate WB gauge/sensor (ordered)
3" Universal Cat with air inlet
2.5" piping to mufflers

I was originally going to use the magnaflow stainless mufflers.... but I'm afraid I'll be a little louder than I would like. I just don't want to sound all raspy. I know it's sort of hard to do on a rotary engine.... Would a resonator help smooth out the tone if I kept the magnaflows?

Or should I go with different mufflers all together? My main goals are to avoid giving myself headaches while cruising, and I don't want to sound like a civic with a coffee can welded to my tailpipes.

 

Alright, so a box of goodies arrived in the mail today



Resonators


Mufflers


And I got this...


To handle these..


I've already got the 3" corksport downpipe. I've got a hi-flow cat coming tomorrow, and I should be all set. Still waiting on my old-school VW boost gauge though.

Decided to go three inch all the way to the "Y", then 2.5 the rest of the way back With any luck, I should get this done this weekend

Also still waiting on my injector resistors...

 

Didn't get any of the exhaust built this weekend. I had problems with everything. While installing the Rtek in my ecu, I believe I may have dropped a bit of solder somewhere I shouldn't have from my crappy solder sucker, or I overheated the board components. So when I plugged the ECU back in, and turned the key, all the solenoids in the engine bay went crazy. And the car would no longer start (later discovered my friend hooked the fuel pump up backwards...).

The stock intake manifold gasket broke apart when I pulled the UIM off to replace the secondaries, but I was able to drive out to the westside of town to get a new one from Turblown.

Found a JDM N374 ECU locally (thanks Gurew) with a knightsport chip already in it, so I can throw my Rtek in it's place without fear of destroying another ECU.

Started the car finally yesterday, only to discover theres gobs of fuel pouring out from somewhere under the UIM. My guess is one of the injectors didn't seat right. But I'm not sure.

So after all that, I haven't touched the exhaust. What a sham of a weekend...

 

Got my exhaust installed Some of the bends didn't come out the way I wanted/planned, but I was pretty impressed. My buddy and I tried to use math, but it didn't work out so well. So we resorted to the tried and true guess and check method. Once I get all the pictures rounded up, I'll probably post the whole build in the non-tech section. Here's a vid. Thanks to everyone that gave me suggestions, and helped out!

Not the best vid, but it works. Exactly the volume level I wanted. Not crazy, but you can definitely hear it . But the mic on my camera stinks....

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I just realized I've just been talking to myself the last month.. lol....

 

Sounds good, but I would have done without the resonators personally. What made you choose to use them?

 

sounds nicee

 

low profile tone! sounds nice.

can u get any underbody pics?

 

One other thing... Wideband O2 sensors are pretty sensitive to heat & pressure, and the temperature coming right out of the turbo (as well as the pressures there) will cause it to get out of calibration pretty quickly, and outright fail more quickly too. A better place for it is right down around the bend in the pipe circled in green in the stock setup picture you posted earlier; I've had mine at this spot (the approximate distance from the turbo is whats important), with a home-made heat shield, for a couple years and things are still good (checked against a known good sensor in the same location)

 

Thanks! I wanted more control over the tone. And wanted it to be modest.

Thanks!

Once I get all the photos together, I'll post some up

I mounted the bung fairly far down the pipe, about 1/3-1/2 of the way down. I really wanted to mount the controller in the engine bay, and not have it strapped to the bottom of the car.

 

Oh, and for anyone ever changing fuel injectors out.... ALWAYS assume the o-rings need replacing. The ones that came on the injectors looked just fine. But one decided it didn't feel like doing what it was supposed to, and sprayed fuel all over the engine

 

You can strap the WB controller on the transmission crossmember, or there was a nice little spot inboard of the frame "rail" that was boxed on 3 sides, right near where the speedometer cable exits the transmission. I don't know if this is only there on 'verts, but it's worked well for holding it, as long as you take care of any and all slack in the cables so they don't drag. I also made a thin aluminum shield that the cable is strapped to, so that it doesn't contact the driveshaft's U-joint (since the wires for mine run up through the shifter hole and around to the passenger footwell to the ECU & gauge)

 

Having some issues with AFR's and jerking/pulsing at casual acceleration. Started a separate thread about. Hoping I can get it sorted out soon.

Oh, and also, turns out I didn't burn up my ECU. Rtek used the wrong hardware when they wrote the software for the chip. I got a full refund