DP question...

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Feb 6, 2009 | 07:01 AM

Brown Falcon

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From: Thomasville, GA

DP question...

Is the outlet of the 3" downpipes 3" ID or OD? I'm just wondering which adapter I'm gonna need to go from the DP to my 4" under the truck when I do it.

Also, how far back does the DP go? Does it end in front of where the stock bolts/flange is? or behind?

Feb 6, 2009 | 09:42 AM

Neal 97 250

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From: Johnson City, TN.

IIRC inside dimension. I could be wrong though
The DP comes down and ends where the cat begins.

Feb 6, 2009 | 10:05 AM

Butch(OH)

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From: ohio

Usualy (note use of disclaimer word right off, LOL) an exhaust system will be designed so that the discharge end of pipes fits inside the inlet of the next unit. In other words your down pipe will fit inside of the next pipe towards the rear. Your next piece will need to be swaged out to slip over the 3" pipe of your down pipe. Mine DP is a 3" no kitty type and ended right where it would have fed it. Make sure you have the kitty elimenator type if you are not planning on using one.

Feb 6, 2009 | 11:20 AM

Neal 97 250

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From: Johnson City, TN.

I had a DP that was made for a cat. It ended with the round swivel type of fitting. I cut the end off the cat to adapt it.

They also make a DP like I have now that is just a straight pipe.

Feb 6, 2009 | 11:37 AM

Brown Falcon

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From: Thomasville, GA

I already have a cat delete. I was looking at the MBRP 2 piece downpipe. I might just have to wait till i get the DP here and in the truck and then figure out if I'll need more pipe or not.
Right now I have the 3.5" stock pipe cut back behind where the cat was then into 4" pipe into a 90* to my 5" stack piping.