exhaust options

[e30polak]

just watched static's video...his setup sounds great.

:up:

http://video.google.com/videoplay?do...58971022829659

[matt]

I'm running an ebay SS turbo manifold, to forget about any restriction problems. I had one of the local exhaust gods setup a 3" down-pipe perfectly down to a 3" vibrant high-flow cat. Then i continue to a 3" borla race muffler (as a resonator), and finally to a 3" vibrant street power - turbo series muffler. The exhaust is by far the nicest 6 cylinder note I've ever heard, but it gets a little loud after 4 grand :shock:, the neighbors hate it. Total was a little under $900.

A prime example of how not to do it. Although the 3" exhaust and turbo manifold may make some sense if you do plan on going turbo later. Then again your choice of turbo manifold... not sure how many times I'll have to say it... :hitler:

Kudos on your spelling and grammar though, it really seems like you're working on it.

[FredK]

For the o2 sensor holes, you can use BMW K-bike oil drain plugs. I can get you a part number if you want.

I have a set of plates techno550 made for me to block off the EGR stuff. Pretty simple with some 1/4" steel plate and a bench grinder.

I went uber balling and bought a Summit Racing brand O2 weld on bung. How can such a small piece of metal cost $6?

Anyway the blockoff plates idea did occur to me; I fabbed a pair up using some SS 304 bar stock we had here at work, but I figured I'd need to run the later style manifold gaskets (3+3)and air injection port gaskets, both of which I don't have. I guess I'll just bite the bullet and pay the $15 and do it that way.

May I make a suggestion?

At a minimum, get yourself a die grinder and a cutoff tool. The Chinese ones from Harbor Freight will work fine for now. The cheapo grinding discs wear out really quickly but they will make you appreciate the brand name ones when you move up to them.

You'll love welding as it's a lot of fun.

I'm all ears!

I have a set of el cheapo die grinders, straight and right angle, a reciprocating saw with some bimetal blades, a 4 1/2" grinder, and some flat metal files. I think I should be able to, um, cobble something together.

I've made some practice welds and I'm still getting the hang of it. I'm getting good penetration, I just need to fiddle with the settings to get a smoother looking bead. Maybe more wire. Maybe a steadier hand. Maybe I just need more practice. :oops:

[matt]

Practice is everything with welding. Practice and machine setup.

If you have an industrial supply house near you, you can use an M18 nut for a weld bung for an o2 sensor.

I think the OBDII headers are worth it... they are very pretty.

[e30polak]

[quote=matt;705416]A prime example of how not to do it. Although the 3" exhaust and turbo manifold may make some sense if you do plan on going turbo later.

Hey man u talk too much shit. I wanted to counter act the dual piping by going big enough with a single exhaust. My car doesn't run lean or rich, i have great throttle response, the exhaust note is guaranteed to be a hell of a lot nicer then yours, and i bet my header and exhaust system looks better and is made just as well as yours.:finger: Get off your high horse, tying to make it seem like you know it all, if you haven't seen it then don't knock on it. The quality of my turbo manifold is perfectly fine for the exhaust setup I'm running. The manifold is well made i guarantee you, don't be fooled by the price tag. On top of that, the route i went is easier, and much less restrictive then running stock headers. If you're ever in the LA area I'll show u how "bad" my exhaust setup is, as well as how well my car runs.

[hugh jass]

A prime example of how not to do it. Although the 3" exhaust and turbo manifold may make some sense if you do plan on going turbo later. Then again your choice of turbo manifold... not sure how many times I'll have to say it... :hitler:

Kudos on your spelling and grammar though, it really seems like you're working on it.

condescending AND a know it all. wow, you're like jordan 2.0, which is too bad, because this board really didn't need another one.

[matt]

condescending AND a know it all. wow, you're like jordan 2.0, which is too bad, because this board really didn't need another one.

Thanks! 8)

[matt]

A prime example of how not to do it. Although the 3" exhaust and turbo manifold may make some sense if you do plan on going turbo later.

Hey man u talk too much shit. I wanted to counter act the dual piping by going big enough with a single exhaust. My car doesn't run lean or rich, i have great throttle response, the exhaust note is guaranteed to be a hell of a lot nicer then yours, and i bet my header and exhaust system looks better and is made just as well as yours.:finger: Get off your high horse, tying to make it seem like you know it all, if you haven't seen it then don't knock on it. The quality of my turbo manifold is perfectly fine for the exhaust setup I'm running. The manifold is well made i guarantee you, don't be fooled by the price tag. On top of that, the route i went is easier, and much less restrictive then running stock headers. If you're ever in the LA area I'll show u how "bad" my exhaust setup is, as well as how well my car runs.

That's not the point... my point is that there is a right way and a wrong way to do things. Are you actually planning to turbo your car? If you aren't, your car will probably sound better and be more powerful with a stockish header system and a 2.5" exhaust. And if you are, get on with it. A turbo manifold will cost an NA motor a lot of power.

[e30polak]

how is it costing me power? i really would like to know how opening up my exhaust would rob me of power. if you mean that i have lost back pressure, then i'm perfectly fine with that. the s52 produces a little too much torque for traction purposes, so i tried to counter act that with bigger exhaust, the obd1 intake manifold, and the 3.25 diff. i'm also planning on getting cams with in the next few months, which will take away some low end as well. but since it looks like you have a lot more experience with building up cars, i would like your input on the power loss with the turbo manifold.

[matt]

With a turbo manifold, you have very short primary tubes (the first tube after the valve) and no secondaries at all. Also, every primary tube has a different length. This is the opposite of what you want in a header... long equal length primaries and secondaries.

There is a lot more that goes into exhaust tuning than just "opening it up." Exhaust velocity must be matched with mass flow potential, and the tubes need to meet in such a way that allows the pulses coming from the valves to pull each other along rather than just bumping into each other as they spill haphazardly into a massive pipe.

[sefb222]

i'm using one of these, modified to fit...

http://www.uucmotorwerks.com/RSC36/

[JeffRR]

I'm planning on running dual 2.5's into a X-pipe then back to a dual 2.5" inlet /outlet magnaflow muffler. It seems like running the X-pipe will get you out of the rasp when not running a cats or resonators.

I'm running a OBD1 S52 with the stainless OBDII manifolds.

As far as flow is concerned the magnaflow E36M3 system uses dual 2.5's, that's behind the S50/52. Without doing a back-to-back evaluation between the different set-ups (dual 2.5's, single 3", dual 2.25's etc) or building a computer model to investigate the dynamic performance, its difficult to determine the optimal solution.

For reference I saw something on the a E36M3 race car (US spec, might have been PTG) and they were running dual 2.75" tubing.

[matt]

As far as flow is concerned the magnaflow E36M3 system uses dual 2.5's, that's behind the S50/52. Without doing a back-to-back evaluation between the different set-ups (dual 2.5's, single 3", dual 2.25's etc) or building a computer model to investigate the dynamic performance, its difficult to determine the optimal solution.

It's not hard to determine the optimal solution... www.headerdesign.com will get you started.

[Mr Deagle]

how is it costing me power? i really would like to know how opening up my exhaust would rob me of power. if you mean that i have lost back pressure, then i'm perfectly fine with that. the s52 produces a little too much torque for traction purposes, so i tried to counter act that with bigger exhaust, the obd1 intake manifold, and the 3.25 diff. i'm also planning on getting cams with in the next few months, which will take away some low end as well. but since it looks like you have a lot more experience with building up cars, i would like your input on the power loss with the turbo manifold.

you are running a turbo manifold on a non turbo car?????

WTF?????

[e30polak]

i did it for the easier exhaust setup, and i plan on turboing the car in the future. the car is fast as hell, despite the slight power loss i might have received from going this route. plus the exhaust system turned out great this way, sounds sexy.