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five inch down pipe?

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Not sure why you or anyone else would need a 5" downpipe? But if would not be very hard to take a 4" downpipe cut it after the bend and get a 5" to 4" adapter to mate it to a 5" pipe. I'm sure a diesel shop that does large diesel engine work could hook you up with one. Or just contact any manufacturer of a 5" exhaust system and ask to buy there downpipe.
 
I made a 5" downpipe since the Pius turbo had a 5" outlet. Clearance is tight betwen the frame and bellhousing near the hole for the barring tool. I think the commercial systems use a 4" downpipe. I suggest buying a 60 deg. bend 41628 and a 45 deg bend with 15" long arms 42249 from Walker and mig welding up your own downpipe. The 60 deg bend has an ID end that will slip over 5" that you will cut off. You can use it at the bottom in case the downpipe does not end up pointed quite straight back, and you need a bit of a bend in addition to a "sleeve" on the pipe running back to the muffler, so it will slip over the head pipe. Spacing of the turbo from the engine will affect its shape and there isn't much room to swing it around and adapt to a different turbo configuration. If you have a 4" outlet from the turbo, you will need a 4-5" adapter and the correct flange. There isn't much room, turbo to firewall, so you will have to cut the flange and adapter tight, as well as the 60 deg. bend.
 
It is a very tight fit but a 5 inch down pipe is possible I went straight down between the frame and engine block, once wraped with header wrap there is NO room. It takes a lot of work (Thanks Jim& Matt) but it can be done. Why do it, to have true 5 inch and be different. I was looking to find a different sound w/ bigger pipe all the way. It is much quieter than before not sure if it is the turbo, ats man or the exhaust but the combination made a big difference.



Craig
 
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thank you for your responces to this. i was thinking it was going to be something i was going to have to make. i was guessing the angles though. Pius sent me a 60* with my turbo, and i was thinking it was 45 at the bottom.



so being that i have a 4" outlet it would go:

exh flange, 4-5" expander, 60* bend, 5" tubing, and a 45*.

sounds like a down pipe to me. :D



correct me if i am wrong. please.



also i have no real reason as to why i want to do this. you come and work in iceland and see what odd things you come up with ;)

lots of extra time to fill, but i am limited to simple things.
 
Those Walker #s have long enough ends that you don't need any straight pipe added in the middle. I suggest grinding the aluminum block plate and bellhousing slightly where it is tight. You can end up with 1/8" + on each side for clearance. The tight spot will be near a mounting ear for a bellhousing bolt and the engine barring tool hole.
 
thank you for that. i wasnt sure as to what all i was going to need, and it takes to long to get anything shipped over here to experiment. you guys saved me a lot fo head ache thanks again.
 
Jim, Craig and I made the 5" downpipe out of the following items:



4" 1/2 marmon flange

4"-5" adapter - cut short as possible

2-90° 5" bends

1-order of cheesecurds

a few feet of 5" pipe

a few feet of 5" flex pipe

some 5" band clamps



Here's what it looks like - don't make fun of my quick Microsoft Paint drawing. :) The thick lines are where you have to glue it together...



The EEP turbo uses a 4" 1/2-marmon flange... the usual flange is a standard 3"/4" v-band clamp.



Matt
 
Just use the 4in down pipe

Cause it will be a really tight fit near the bellhousing,you might break the down pipe as the engine torques the pipe will hit the frame which might also damage the turbo. Use a 4in down pipe and splice it to 5in near the trans crossmember with a 4in to 5in adapter. Merv
 
HUH? Don't tell Sickly. He has been running a 5" downpipe very happily for a couple of years. Didn't dent it, it hasn't broken, flows a lot of gas where it is hottest and needs the volume in the pipe. But then, if your ride doesn't make over 570 hp, it doesn't matter.
 
I think its easy to run a 5in with twins

Cause the big turbo is down low where the 5in pipe clears the frame. I may be wrong,but with a single turbocharger its a bit more difficult. Then again with a single you may not need a 5in down pipe. I'm assuming the truck we are discussing is a single charger.
 
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