[fasttoys450]

i have 1994 7.3 iam wanting to put a 4in down pipe on i did one on my 03 6.0 is it about the same or harder.I also cant find one in 4in for my truck does anyone have any pics of putting one in there truck.

Thanks

 

[cumminsdude2001]

i have 1994 7.3 iam wanting to put a 4in down pipe on i did one on my 03 6.0 is it about the same or harder.I also cant find one in 4in for my truck does anyone have any pics of putting one in there truck.

Thanks

The aftermarket companies like banks bullydog and MBRP only make them in 3" because of the firewall clearence, even then you stil have to bang in the firewall some for additional clearence, but not by much. the 3'' downpipe to a 4" exhaust is more than enough for the engine to breathe. I did one when I had my 97 and doing that alone made a big diffence in the top end. Getting rid of the factory crushed pipe is the best thing for the engine. I didn't even upgrade my exhaust, just the downpipe and I noticed the difference.

 

[Zaairman]

No way in hell you're gonna fit a 4" down pipe without MAJOR modifications.

 

[balz out]

cut out your firewall they are over rated anyways... weight reduction and good ventilation :hump

 

[Stacked6600]

I put a 3" 2 piece down pipe on my 95 and it was a pain and yes a large hammer and pry bar for the fire wall is a must. Dont even think about a 4" :bash 3" down pipe to a 4" exaust is fine. Cumminsdude is right is makes a difference even with the stock exaust with muffler delete.

 

[crzycowboy]

Yep, even our downpipes are 3" for that year Powerstroke. A lot of people think bigger is better, and in some cases it is...but as for a down pipe...not so much..sometimes bigger means less throttle response...and what fun is that?

 

[woodsman]

Am I understanding this correctly, different year OBS trucks had more or less room for a downpipe? I was under the assumption that they were all the same.

 

[crzycowboy]

Am I understanding this correctly, different year OBS trucks had more or less room for a downpipe? I was under the assumption that they were all the same.

No, the 1994 - 1997 had the same little room for a 4" downpipe..LOL..sorry I guess I should've been more clear.

 

[cumminsdude2001]

I put a 3" 2 piece down pipe on my 95 and it was a pain and yes a large hammer and pry bar for the fire wall is a must. Dont even think about a 4" :bash 3" down pipe to a 4" exaust is fine. Cumminsdude is right is makes a difference even with the stock exaust with muffler delete.

From what I found out the old body style trucks actually have a good straight in and out flow muffler a lot like the aftermarket mufflers, with the acception of it being quiet, that is if you want it quiet, if not by all means a muffler delete pipe.