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Old 04-14-2004, 06:37 PM
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Default Big pipes or little pipes?

So I called my new friend Dennis at bbexhaust.com and asked about B&B's headers for an 88 Carerra (3.2L). The "complete kit" with heat costs $2755, and comes with 1 5/8" pipes in the headers. Dennis said this is appropriate for a stock 3.2, as mine is. The complete kit with 1 3/4" pipes is $300 more.

So which should I get? Do big pipes on a stock engine hurt? Is there a performance difference between a 1 out and a 2 out muffler? Is it worth it to buy 4 1/2" outlets as opposed to 3 1/2" outlets?

Too many decisions.

Bob
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Old 04-14-2004, 08:55 PM
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Stock engine = small(er) pipes. Yes big(ger) can hurt. There can be big difference between 1 out & 2 out & 4.5” can be better than 3.5” outlets. Did I ever tell you I worked for Uncle

Pipe size can help or hinder scavenging of the exhaust gasses. To big pipes on stock engines can really hurt bottom end & not really help on top cause the engine doesn’t “pump” enough air to take advantage. Larger outlets won’t help if muffler design isn’t optimized to maintain proper backpressure. To get real data I suggest you “google” for hot rod sites. There was a TV show on last weekend on one of the car channel’s about sizing exhaust tubes, collectors, etc. I still think that SSIs (around $850) & a good sport type muffler ($200 - $400) or even a stock Porsche 2 in 1 out will give you more bang for the buck.
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Old 04-14-2004, 11:37 PM
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Great Scott! Bob is morphing into another MacPipes!
We need an intervention, and quickly - before mild mannered Bob starts spewing smack as well.
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Old 04-15-2004, 08:42 AM
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Quote:
Great Scott! Bob is morphing into another MacPipes!
We need an intervention, and quickly - before mild mannered Bob starts spewing smack as well.
ROFL
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Old 04-15-2004, 09:21 AM
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Little pipes Bob. I just had a similar conversation with my Daughter about her big/small block chevy truck (400sb). She wanted to put 'duals' in. Hard to convince her that a stock V8 actually makes more power with a correctly sized crossover or H configuration than duals. Granted, it sounds awsome with the duals ...

Also, Google around. I think there have been some uncomplimentary things said about BB exhaust.
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Old 04-15-2004, 10:25 AM
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Bob:

FWIW . . . you need a certain amount of back pressure for any engine to perform in the low end.

I put the SSIs that were designed for the 2.7/3.0 motor on the 3.2 and there is a world of difference between the SSIs and the stock set up. I have the 2 in 4 out monza set up and seem to have plenty of power as compared to other 3.2s. SSIs have heat too.

On the issue of headers, SSIs are true equal length headers covered by sheet metal. When I put the 3.2 in my car I spoke with John (the founder) at SSI and he said that the 2.7 units would work fine and he was right.

I believe they have 3.2 units now, but not sure.

You are welcome to test drive the car.
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Old 04-15-2004, 04:04 PM
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Bobby boy, the pipes, the pipes are calling.

The size of one's pipes has a direct relation to the amount of smack one talks. For instance; I've been driving my wife's VW Passat, which has very small pipes, for the past few months while doing my rebuild. I have noticed people no longer leave the room when I walk in.......weird.

"Loud pipes save lives"
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Old 04-15-2004, 04:46 PM
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Wait a minute! Are we still taking about exhaust pipes? Because size doesn’t count in electronics either.

So Bob are you thinking about a rebuild? One full point in compression is worth about +10% HP! If’n you gotta buy pistons anyways, why not? 964 cams? Euro computer? Bored out intake runners? 3 angle valve job? Maybe you should be “liv’n large” like "M Pipes".
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Old 04-15-2004, 09:28 PM
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I think I can sneak an exhaust on the car, at least in terms of $$$, without Angela noticing. An upgrade rebuild is out of the question.

It's gonna have to come in under $4k, which the BB makes but only just. I'm worried about the noise, which I don't want to be objectionable.

Pelican sells SSI's, and they seem cheaper than the BB setup. But my wrench wants to put BB on it.

I really have two concerns - MD emissions inspection, and noise level. I'm due for an inspection this May, so I'll be good for 2 years. If I slip the exhaust in after MO, it'll be there for SP. Whoo eee.
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Old 04-16-2004, 03:00 AM
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I have SSI's on my SC and passed MD emissions just fine. Actually, I failed the first time, turned my mixture screw to the left about a 1/4 turn and passed the second time.
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