Exhaust Options

[bigdraft]

Ok, another question for ya.........on a 89 7.3 IDI, what exhaust options do you have? I know there is no 'down pipe' so w can start there. Can you go off the manifolds and run like 3 or 4 inch straight out the back with no muffler? In case you guys dont know yet......I know NOTHING about the IDI motors.....yet. Please help.........


Kevin

 

[towcat]

If local PD turns a deaf ear to the racket a straight pipe makes, you're OK. No turbo on a IDI will make for a very loud exhaust note. with a turbo, you're civil below 2k RPM.

 

[bigdraft]

Straight pipe is kinda loud on an IDI huh? What size pipe would you go with? I'm assuming it's like any other vehicle and the bigger the pipe the better? Would say 3 inch be a good size? Maybe 3 inch WITH a muffler of some sort, and a 4 or 5 inch tip??????


kevin

 

[Dsl_Dog_Treat]

Kevin,
I have 3" system starting from the y-pipe back with a Dynomax proflow muffler in the mix. When I am getting on it, she sounds like a worked up big block gassers going to town. With the style mullfer I have on there, I still get some noise and even a little cackle around 2800 rpm.

I tried just a glass pack for awhile but got kinda annoying after awhile. Sounds good but too loud.
The guy at the exhaust shop told me for the N/A motors anything over 3" was a waste of money as there isn't enough flow to need 4" or bigger without a turbo.
I have to agree with him as all of the locals use him for their system builds as he had been in the business for over 30 years.

 

[160k87F250]

I run a 3" y-pipe straighted piped into dual 2.5" tailpipes. The tailpipes have 3.5" stainless tips that act like megaphones. It's loud when getting on it, and in some RPM ranges it has a cackle to it. I've been thinking about adding a 3" straight through muffler to it to tone it down a bit. So far, local law enforcement has not bothered me, yet. :Sly
John

 

[PackRat]

A buddy of mine had an IDI, with headers and dual 2 1/2's, with glasspacks. Sounded awesome(for a Ferd), but was a little noisy, when you got on it.