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Exhaust for Clean Power

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Old Feb 13, 2007 | 04:21 PM
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Default Exhaust for Clean Power

I am considering the toptions for a new exhaust on my 86.5. As important to me as additional power is cleanliness, not of design, but in terms of emissions. I also want to keep it tolerable for sound. I can handle louder than stock, but not X-pipe, no-cats, RMB loud.

I am considering:
X-pipe, the high-flow 300 cats and maybe a pumpkin or a flowmaster at the end. Obviously, the 300 cats are ciritical to keeping it clean.

Would like to hear other layouts that might give me a little boost, a lot of clean and keep the sound tolerable.

Thanks,
Matt
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Old Feb 13, 2007 | 04:26 PM
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Matt,

Did you see my post a few days ago about my new Motorsport crossovers? I can't get over the difference, and, I passed NJ emissions with flying colors with the high flow cats. I highly recommend them.

I didn't change anything else on the exhaust system, and it sounds just a bit throatier and it's definitely got more kick. Ed Hughes just did the same thing.
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Old Feb 13, 2007 | 04:28 PM
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Originally Posted by NJSharkFan
Matt,

Did you see my post a few days ago about my new Motorsport crossovers? I can't get over the difference, and, I passed NJ emissions with flying colors with the high flow cats. I highly recommend them.
So, you kept the original rear muffler? Are these Carl Fausset's setup? Are his high-flows 300 or 100?

Thanks,
Matt
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Old Feb 13, 2007 | 04:34 PM
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Matt,

Yep, original manifold and exhaust system from the cat back, just plugged in the new crossovers, high flows (I think they're 300 but I'm not sure) and a new O2 sensor. Here are the inspection results:



Sorry for the shameless plug, I was driving with a red sticker for 5 months. Now I'm good until 9/08!

I got the 'Dave Lomas' Crossovers from Motorsport in stainless steel.
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Old Feb 13, 2007 | 04:36 PM
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Hey Matt,

Carl resells our X-over. The high flow cats for the X are 100cpi. We no longer sell the 300cpi for the X as the 100's are as clean as the factory cats with almost no restriction. I do have 300cpi cats available for the Y pipe since the older 16 valve engine control systems are not as efficient.
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Old Feb 13, 2007 | 04:37 PM
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Dave, you guys ROCK!

So mine are 100 cpi then?
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Old Feb 13, 2007 | 04:41 PM
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Originally Posted by Ketchmi
Carl resells our X-over. The high flow cats for the X are 100cpi. We no longer sell the 300cpi for the X as the 100's are as clean as the factory cats with almost no restriction. I do have 300cpi cats available for the Y pipe since the older 16 valve engine control systems are not as efficient.
Cool and thanks. So, can the 300 cpi be fitted to the X by special order?

If I could be even cleaner than stock original, I would be thrilled. It sounds like that's how I want to go. I can go 100 if the 300 isn't available, but would rather be as clean as possible and willing to give up a few HP to do it.

I remember you had said before that the new 300 cpi have pretty good flow.

Matt
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Old Feb 13, 2007 | 04:43 PM
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Dude,

Check out the readings. I don't know how you're going to get cleaner than that. Especially at the cost of some flow!
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Old Feb 13, 2007 | 06:50 PM
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The cats for the crossover are 2.5" and the cats for the Y-pipe are 3". We do not stock 300cpi in 2.5" any more. Sorry...
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Old Feb 13, 2007 | 07:02 PM
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Congratulations on making a clean choice. Maybe Dave could PM you with a source for the 300 cats? or just take a look at offerings from Magnaflow and others. Magnaflow is also my choice so far for a tailpipe muffler.
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Old Feb 13, 2007 | 07:24 PM
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I'm much more horsepower biased than clean, if I can have both I will but...

The Magnaflow cats are the 400cpi ceramic brick type and are good for about a 14 horsepower loss. I also have no guarantee that they are any cleaner than the 100cpi metal matrix cats I had made. I am sure you reach a point of diminishing returns, exhaust can only be made so clean without going alternative power.

Yes Mike, you have the 100cpi cats, pretty clean for an 85' with 205k on it!
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Old Feb 13, 2007 | 10:17 PM
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Yes Mike, you have the 100cpi cats, pretty clean for an 85' with 205k on it!
I'm pretty happy with it. It's really dialed in right now. I guess this also answers the question in another recent post of mine about whether or not the performance chips affect emissions.


Sometimes, if you're lucky and good, you can have it all .
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Old Feb 13, 2007 | 11:08 PM
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Originally Posted by Ketchmi
The Magnaflow cats are the 400cpi ceramic brick type and are good for about a 14 horsepower loss. I also have no guarantee that they are any cleaner than the 100cpi metal matrix cats I had made. I am sure you reach a point of diminishing returns, exhaust can only be made so clean without going alternative power.
I figure there is a sweet spot that suits my desire to be clean while not losing too much power. 14 hp is too much because it negates a lot of the X-pipe gain. I haven't looked at Magnaflow cats; I am possibly interested in a Magnaflow muffler, though.

The original question, though, is what in addition to the X-pipe, going from front to back to gain horsepower and burn cleaner, is out there.

Matt
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Old Feb 14, 2007 | 08:37 AM
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Dave,
how much are the 100 cpi's?
I could not find them on your website.
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Old Feb 14, 2007 | 08:41 AM
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I recently installed an x-pipe to test and the car stinks like an od school bus. When I get on the gas at high RPM's, I leave a brown trail like a diesel Powermax...
So it's either CATS or take the x-pipe out and place the original cats back on the car.

I also compared the car to Cameron's car, which is identical running 7PSI boost. It seems like the x did not make any noticeable change in power. The cars run exactly the same.
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