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Old 02-06-2010, 02:32 PM   #1
70stroker
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exshaust question for bbc

Im sure some of you know i am rebuilding my supercharged bbc. While it was out i wanted to take car of the ground clearence issue with the headers. I ordered a set of the headers "joker" from this site was making just for these trucks. they are 2 inch primarys with a 3.5 inch collector. I currently have 1-7/8 primarys with 3 inch colletors and 3 inch pipe all the way back. I am having a hard time figuring out what to do.

this is mostly going to be a street driven with a few track passes a year. I think 3.5 inch exshaust all the way back might be a little to much, and cause me to loose some lowend torque. Plus my 3 inch and mufflers only have about 1000 miles on them.

should i run new 3.5 inch and get new mufflers, or get a reducer at the collector down to 3 inch?

whats your opinions?

thanks
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Old 02-06-2010, 02:39 PM   #2
dan76
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Re: exshaust question for bbc

Are you on a budget?
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Old 02-06-2010, 04:14 PM   #3
70stroker
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Re: exshaust question for bbc

i have about 6500 in my motor now. so no and yes, i mean i dont want to spend 1500 on a exshaust, but i can give up 300 to 500 for a new exshaust system if need be
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Old 02-06-2010, 05:01 PM   #4
ProStreet68SB
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Re: exshaust question for bbc

i think you'll be more than happy staying with the dual 3in setup you have now.
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Old 02-06-2010, 05:05 PM   #5
70stroker
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Re: exshaust question for bbc

but will a 3.5 inch collector reduced down be ok
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Old 02-06-2010, 09:42 PM   #6
Super73
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Re: exshaust question for bbc

Put dual 3.5" cut outs 16-18" behind the collector, then reduce it to your 3". When your at the track, uncork it. When your on the street, leave it corked. Cheaper than running a full new system with the benifits of getting everything you can out of it.
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Old 02-07-2010, 09:49 AM   #7
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Re: exshaust question for bbc

3.5 reduce to 3" and you will be OK.
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Old 02-07-2010, 10:55 AM   #8
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Re: exshaust question for bbc

Unless your\e running a real big cubic inch motor, I'd reduce it down to 3". I like running mine through the mufflers at the track. I think going fast and being quiet is cool. Good luck
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Old 02-19-2010, 01:35 PM   #9
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Re: exshaust question for bbc

Quote:
Originally Posted by bigsnookmaster View Post
Unless your\e running a real big cubic inch motor, I'd reduce it down to 3". I like running mine through the mufflers at the track. I think going fast and being quiet is cool. Good luck
I run 1 7/8 in tubes into a 3 in collector that stops down to 2.5 in for my ZZ572. Stay with the 3 in to save $$ cause you probably will not notice the loss in low end torque.
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