Here's a step-by-step instructions for posting pics...

https://www.dieseltruckresource.com/...d.php?t=187910

Or you could email them to me dan@srt.com

 

Part number is 3927811. Cost is around $47. You can order it from www.reliablegoods.com.

 

I hope i didnt screw up how the page loads. Sorry i am newbie at pic posting

 

I was under the impression that no 2nd gen downpipe would work on our trucks?

 

QUESTION!!!

If you are not running a high tweaked 12V what good is the 4" downpipe???
I was told that running simple mods that anything over a 3" or 3 1/2" downpipe actually HURTS performance! My last truck was a 1993 with simple pump mods, 3" downpipe, 4" straight back, and a 4" tailpipe from a 2005 Dodge 3500 and a 5" tip.... Great sound and performance!.
I found either a 3" or 3 1/2" for the 1989 to 1993 12V trucks on ebay for around 150.00 and the downpipe for the IC engine comes with the heat shield aready installed. go to ebay parts and type in cummins downpipe!

Let me know if the 4" helps or hurts with simple pump mods. I am waiting on my 92 Dually to get out of the spring shop so I can turn it up and fix the ol'man original exhaust system.

 

That might be ture but biggers is always better77machomopar how far is it from the flang to the down side of the downpipe?

 

Proram put one on his truck and if I'm not mistaken I remember reading that he also did a 5" system as well. I did see some pics on here but can't remember exactly where. I'm sure he'll chime in and tell you exactly what parts you will need or say where to look (I hope )

 

I don't want to jinx myself, but with any luck I will have the 2nd gen elbow/ Dp and 4 to 5 exhaust on tonight. I will take pics.

 

'lil bigger Looks cool, I'm gonna go do mine

 

I will measure it tonight. I just used 4" 90 degree angles with 6" legs. the leg that is welded to the flange was cut shorter so it wouldnt hit the trans, firewall, etc. The pipe is the same overall length of the stock pipe.

 

Since my motor is a Non- I/C the bigger downpipe has helped with my egt's. I havent noticed any decrease in power.

 

I believe all this is true on a normally asperated engine whether it be an oil burner or a gasser. Size and length of the exhaust manifold, ie. headers, determine torque and horsepower characteristics due to the scavanging effects of the exhaust pulses. But this isn't the case (or not nearly so much) with a turbo charged engine. Especially one running high amounts of boost. The intake side PUSHES the air through the engine rather the exhaust side SUCKING the air through the engine (or, if your a scientist, rather than the atmospheric pressure pushing the air through). I think what we really want to do in our cummins engines, and other turbo charged engines, is make it as easy as possible for the hot gasses to escape to help facilitate the fastest and most effiecient turning of the turbine which helps us create more boost. We also tend to worry about too much heat around our turbo area. Smaller pipes plainly restrict gas flow thus creating more heat, ie. EGT, in the turbo area. From a heat engine point of view, the more heat we can hold in the engine and turn into usable energy the better. But we are limited by our materials. If we hold too much heat things tend to melt, especially aluminum pistons, and things tend to scorch and burn, especially turbo parts and the oil the lubricates it cools it. So lets let those gasses go! As fast as possible please!

 

Well I got it on. Cast elbow, 2nd gen dp, 4" to behind t-c, and 5" from there back. Was fairly easy and souns mean! Thanks Scott!

 

What did you use to go around the T-Case, was it a home made piece or did you get it from a parts vendor. I am tossing around using the Rip Rook 4" dp or going with the second gen part but right now I have a 3.5" pipe going past the tcase and hate to go from 4" to 3.5" back to 4" then to the 5" stacks. I think that it would be defeating the whole purpose of the 4" dp.

 

I used four 4" 45* elbows. Get the shortest ones you can. I have pics of the pipe I made, will post tomorrow.