First off, that part number is the Cummins number for the elbow to downpipe clamp.
Secondly, I have not done this yet because I'm still rounding up parts for my exhaust.
And thirdly, when I had my 03 truck I went to a full 4" exhaust including a Banks 4" DP which did away with the restrictive stock elbow. My EGTs immediately dropped by 100 degrees. Based on that, I would say this mod is well worth it because we will also be getting a more efficient turbo pushing a bit more air so temps may even drop a bit more. The drawback I see is the possibility of a bit more lag but I think it will be minimal....

 

lag? no way , that is the one thing I miss from the stocker, may act a tiny bit different, but just waitin at a light and smashin the skinny, you are off like a shot.

 

Well, I'm speaking from the perspective of a only slightly modded truck, without a lot of extra fueling, going to a larger turbo. It was the stock size on your truck but it is larger than my stocker.....

 

I've run my HE351 with stock fueling & there is NO noticeable lag over the stock 341 turbo. The goals with my truck have been to run around 100 hp over stock with lower EGT's than stock. I'm currently running SMARTY revo on SW5 & around 38 psi boost. EGT's reach 1200' ONLY on a heavy footed uphill tow. MUCH lower than stock & increased fuel mileage also.

 

I have some pictures I will post up later but i removed my HE351 to do some work/measuring for my upcoming turbo projects and I pulled out my new set of calipers and went to town.

Believe it or not, the exhaust turbine wheel on the HE351cw 04.5-07 5.9 liter has a 65mm x 58mm exhaust turbine wheel. This means that essentially, the minor 58mm exducer is the same size as HE341, HX35's, etc. The major 65mm inducer is larger than any of the previous turbos. This means that the HE351 should have a more efficient turbine wheel.

I remeasured the compressor and it's definitely 60mm minor inducer x 85mm-88mm major exducer depending on whether you measure blade tips or flat back plate of the compressor wheel.

 

That's good to know Under-Pressure.
Big Blue24,you are getting too deep for my tired brain. I'll just absorb where you said and that's good enough for me.

 

So its either all or none?

Meaning we can swap the 351 directly onto the stock exhaust, otherwise we will need both the downpipe and the elbow?

 

"elbow is the cast piece that attaches to the turbo. Downpipe is the pipe attached to the elbow"

SO, since I have a 5" MBRP straight pipe exhaust........was the stock downpipe replaced in the exhaust kit?

I will have to look at it tomorrow and see....

 

That is correct. You can retain the stock 3 1/2" elbow & downpipe with the HE351 or use the 04.5+ 4" elbow & downpipe. Exhaust brakes & aftermarket large downpipes for the 341 turbo will bolt right up to the HE351 also. I did get a noticeable EGT reduction when i put the 4" elbow & downpipe on my truck & would certainly recommend it.

 

Your downpipe was probally changed also. I'd certainly use it with the HE351.

 

So.....with all that info, will my MBRP exhaust and MBRP downpipe, which is obviously for an 03-04 truck (with an 03-04 elbow) still bolt direclty onto the 04.5-07 elbow

From MBRP's website:
"5.9L Turbo Back, 5" Single Side Dodge 2500/3500 Cummins Fits 2003-2004 Configurations"

"The turbo back type exhaust system mounts directly to the turbo......."

 

I don't think it will work with the 04.5+ elbow as your 5" downpipe probally necks down to 3.5" to fit the 03 - 04 elbow. I would use what you have as it will bolt up to the HE351 & probally be just fine. How are your EGT's now?

 

You will either need a new MBRP downpipe or you will need a new flange to weld onto your DP after you cut the 3.5" section off of it.....

 

Thanks for the info....

I rarely see 1000 at WOT

Typically around 600-800 cruising around and on the highway.....

 

1000 ? where is your pyro probe, pre or post turbo ? and what levels you running on the smarty and pod % ??