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Exhaust system setup (diagram)

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Old 11-18-05, 03:21 PM
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Lightbulb Exhaust system setup (diagram)





I was wondering if I could get some feedback on this setup, please excuse the rough sketch. The RB header is the collected type and this is for a 12a stock port, possible streetport later on (much later on, lol). Pt 1 is right now so I can mount the header, Pt 2 is for when I can get the money.

Midpipe: 2.5" piping into a midpipe with either a round type magnaflow or a dynomax bullet.

Muffler: 2.5" piping with mandrel bends, over the axle, into a magnaflow round type with downturned tip.

Aluminum heatshield over the header, mounted on exhaust lugs also.


Now for the questions:

1. Should I have some sort of transition pipe from the 2" header outlet into the 2.5" piping?

2. Would the volume/tone of the mid pipe + stock muffler be somewhat equivalent to what I have now (no cats, cheap fiberglass packed resonator, stock muffler)? What about with the new muffler in place?

3. Any problems with the heat shield/anything?


Thanks for your help!
Old 11-18-05, 05:21 PM
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I guess it would except maybe a little quieter. But you are very good at art very nice sketch!
Old 11-18-05, 05:57 PM
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make sure your presilencer is ss packed. a magnaflow 4 inch will work. also, id go 2.25. 2.5 is pretty large. its heavier and more expensive. the magnaflow setup will sound great though.
Old 11-18-05, 07:27 PM
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wow, you sketch pretty good! I've tried so many times to draw an rx7, but they all turn out like crap.

Anyway, yeah, the setup looks great.

Aren't heat shields supposed to be made of steel, not aluminum, (because Al transfers heat faster), or am I wrong?
Old 11-18-05, 09:20 PM
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that would be pretty good, excet i think turn downs are gay, but as long as your no aiming to please me..your fine
Old 11-18-05, 09:31 PM
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Originally Posted by perfect_circle
that would be pretty good, excet i think turn downs are gay, but as long as your no aiming to please me..your fine
These turndowns serve a purpose, in racing anyway. I race in SCCA, and we are tested for sound, 103 Decibels is the max. They test the sound from one side of the track...if you run a rotary, your sound is usually more than 103 db, if you have a good flowing- non restricted exhaust. Thats where the turndown comes in handy, point it away from the sound meter...and you should be OK. If your too loud youll get disqualified or even black flagged and can't race till you quiet it down... So if you take your 7 to a track day, road racing...the turn down could come in very handy! Just my $0.02. Carl
Old 11-18-05, 09:34 PM
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Originally Posted by rbf41182gt
Aren't heat shields supposed to be made of steel, not aluminum, (because Al transfers heat faster), or am I wrong?
Yes, you're right
Old 11-18-05, 10:04 PM
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why do the exhausts go over the axle on se's?
can they go under the axle fine?
thanks.
Old 11-18-05, 10:18 PM
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The exhaust goes over the axle on all 1st gens. Clearance, why else?
Old 11-18-05, 10:33 PM
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Originally Posted by perfect_circle
that would be pretty good, excet i think turn downs are gay, but as long as your no aiming to please me..your fine
Apparently having the exhaust directed downwards is supposed to reduce the sound volume quite a bit without sacrificing flow, although Camocarl does bring up a good point that I didn't realize before. I'm kind of afraid of the car being too loud so the tip is there to tone things down a bit. Would this setup be significantly louder than what I have now?

Oh, and about the heatshield. I thought aluminum would be good because of its good heat reflectivity and absorption properties. Isn't it able to absorb more heat than steel? Thanks for everyones help.
Old 11-18-05, 11:06 PM
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People have done this exhaust system before..pretty much same style. I think it will be too loud. Im running a copy of a Racing Beat Streetport Exhaust system, with dual presilencers, and an Edelbrock RPM Series muffler..its way loud. But I do think I have toasted the presilencers...Ill have to replace those with SS packed Silencers to see if that fixes it, or gets it quieter. Id be intrested in this setup...Just what I was thinking...but maybe you should have 2 presilencers?? The magnaflow is a very well flowing muffler, so it will be loud. Carl
Old 11-18-05, 11:07 PM
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Originally Posted by EonBlue
Oh, and about the heatshield. I thought aluminum would be good because of its good heat reflectivity and absorption properties. Isn't it able to absorb more heat than steel? Thanks for everyones help.
There are a couple of things going on with a heat shield.

Basically, you're trying to block radiative emissions from the exhaust to the intake. Raidative emissions, for reference, is heat that's transfered from one object to another through electormagnetic waves. The other purpose of the heat shield is to keep the hot air that's coming off the exhaust from swirling around in the engine bay and making it's way into your intake or from heating up the intake of the engine.

The object is to keep the heat shield as cold as possible as it absorbs the radiation from the exhaust and helps redirect the air from the exhaust out under the car instead of back into the engine bay. The conductivity of steel is terrible compared to aluminum, so it will do a better job of keeping the heat on the exhaust side of the shield and keep the intake side cooler.

Also, make sure the shield is as polished as possible. This minimizes the amount of heat that it will absorb through radiation.
Old 11-19-05, 01:07 PM
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This is my super exhaust sketch
Attached Thumbnails Exhaust system setup (diagram)-josh-exhaust.jpg  
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