Exhaust Question 2001 7.3

[montanafos]

Guys,

Hoping for a little help. I just picked up a 4" turbo back SS Dynomax exhaust and am looking at the exhaust on my truck and trying to determine if it's already been upgraded at some point. What I'm measuring is a 3 1/2" diameter pipe. The down pipe is 3" and about a foot after the down pipe turns 90 to the rear of the truck it transitions to 3 1/2" from there back and does have a muffler in line. Would this have been standard? If not, will I really see much benefit by going to the 4" turbo back I have? Finally, should I just move to a 3 1/2" down pipe and tie in to the existing system? Thanks!

[jbeasts10]

sounds like you have stock exhaust.You should see lower egt's with the new exhaust and might even feel a little stronger.

[scagle1]

Yes that is the stock set-up. I took mine in to have it straight piped and told them i needed three feet or so of 3" put in place of muffler and was corrected , he told me it was 3-5/8 and ended up welding in a piece of 4" as that was all he had available. Seemed to be a little more responsive after the straight pipe though. Let us know if you put it in and notice a diff. in EGT temps.

[montanafos]

I'll be doing the exhaust sometime in the next couple weeks and will post results. Thanks for the help.