well, when i was changing my oil at a friends shop up on the lift the other night, i noticed that on my 92 325i, in the bottom of my acs muffler there are some rust holes, and my cats seemed to be stopped up....being that we have no smog laws in alabama would it hurt to have my exhaust guy run new dual pipes from the manifold all the way back to a new muffler? If i can't get a dual in dual out muffler for a decent price will it hurt to go from two pipes to one into the muffler and then two out of the muffler? thanks for any help!!
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Originally posted by Scarface@May 21 2003, 10:12 AM yea this guy does alot of v8's and he is a whiz when it comes to fab, he fabs headers for hondas, and v8's all the time, also did one on my 4 wheeler! So it is ok to go with no cats???
you might loose a little torque with no cats actually...
Originally posted by cam540@May 21 2003, 07:43 AM I am pro custom exhaust, its usually cheaper too. Just make sure you go to a shop that knows what they are doing.
PS - I would trust an American style(i.e. mustang, camaro) shop over a ricer shop.
just say no to rice...
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1) Make sure it uses mandrel bends
2) Talk to the guy about getting a stepped system (the pipes would go wide in diameter the farther out from the headers they go. Stepped exhaust are of the most efficient design)
3) If you have no cat laws then have them removed, it would be one less thing to worry about. The torque loss can be made up with other mods for low end power.
4) If you can get new headers, or get them fabricated for you, then see if you can get the headers in a stepped design also. The pipes should get larger in diameter as the get to the collector (i.e. - 2 1/4 inch diameter should step to 2 1/5 at the collector).
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i'm not sure that i would go straight pipes all the way, but its your ride. if you don't have enough back pressure it can actually cause a greater lose of power than sometimes having too much.
i was considering running dual straight pipes before, but i'm not gonna risk the lose of power. your custom exhaust guy can probably tell you what to expect from it, but most often straight pipes are done on larger vehicles such as v8's (what you said he most frequently works on).
I found a few sites with really good deals on catalytic converters and o2 sensors.
oh thats another thing, you may get error with your o2 from straight pipping. if you don't use them you will get errors for sure, and if you do then the exhaust may be too rich when it meets the o2 sensors and you'll get errors that way.
if you want those sites that i bought my stuff from i'd be glad to help, just im me.
haha, you're right! didn't even notice that, haha. looks like "mode310" is spamming with advertisments for his company or something, haha. i think these post should be removed from this thread as they are not contributing to the original question or author. post 11 and down should be deleted.
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