First off, check this thread if you're wondering what I'm talking about to catch you up to speed: https://www.ford-trucks.com/forums/s....php?p=3679917

The o-rings came in over the weekend, so I went to work pulling the turbo off the truck so I can compare the two. I found some interesting results.

First thing I did was to pull the 1.15 A/R exhaust housing off my truck turbo to see if it would fit the van turbo. This would tell me if it really was designed for the truck turbo, or if it was just a van turbo. Much to my suprise, it didn't fit the van turbo. So, it really was designed to fit the different trim of the truck turbo's exhaust wheel afterall. Just to be sure, I then dropped the van turbo housing onto the truck turbo. There was a noticeable gap between the vanes and the housing. I can see how this would cause a loss in boost. However, the housing designed for the truck didn't have that gap at all.

But, since I had the turbo's all out and apart on the bench, I decided I'd put the van turbo back on just to see if there is a difference in performance, since it does actually have a slightly larger turbine wheel. To make sure the only difference I was testing was the exhaust side, I used both the compressor wheel and the ATS housing that were on my truck turbo.

Reinstalled everything and took it out for a drive. There is virtually no difference in performance. Peak boost numbers didn't change, EGT's didn't change, and lag is virtually the same. Turbo lag may be just a little more, and I mean just barely, with the real van turbo, but it's only noticeable because I was specifically looking for it. The only place I noticed it was in the 80 HP setting on the chip, trans in OD, the truck turbo with the 1.15 housing would not really light until about 55-56 MPH. The van turbo lights hard at about 59-60 MPH. That's the only place I noticed any difference in the way the turbo performs.

So my conclusions are this: the 1.15 housing that Shop Diesel sells is really designed for our truck turbo, and I wasn't losing any boost. It and the van turbo perform nearly identical. Since the van turbo's what's on the truck now, I'm leaving it in place. I'm out a bit of money, but to me it's worth it to know for sure what I've got, and also to be able to pass the information on to you all. Which would I do if I had to do it all over again? Depends on which I can get cheaper. When I bought the housing for the truck turbo, it was cheaper than what used turbo's were going for on eBay. But, if the van turbo is cheaper, I'd get it.

 

You need to check drive pressures to see if there is any real difference. Connect a boost gauge in the exhaust tube that you plugged to read the drive pressure. If they seem to be the same in performance the lower pressure is the one you want.

 

So......... what are you doing with that extra exhaust housing.

 

That thought definately crossed my mind, but unfortunately it was after I had already pulled the truck turbo setup off. I'm relatively content with the performance of the van turbo setup as it sits now, and even though the compressor wheel is different from your old setup, I'd imagine that the driver pressures are similar. Given my rate of change with this truck, it's likely that I'll have a different turbo on it in a matter of 6-8 months too.

Question about the drive pressure gauge. How did you keep the soot out of that little tube, and how did you keep it from melting? I guess I could always just use and electric gauge. Convenient that it's a 1/8" NPT port on that little tube.

 

No plans for it I guess. PM me if you've got something in mind.

 

Use copper in the engine compartment then switch to plastic in the cab. If you use copper all the way the gauge acts like a megaphone and you will hear all the engine noise.

 

jt, did the housing from shopdiesel require the flange adapter like the van turbos do?

 

Thanks Kevin. I'll try the copper route for sure. Drive pressures are something that I'm definately going to want to start paying attention to as the buildup of this engine progresses.

Wilhntr, yes it did require an adapter of some sort. Same type as the van turbo's use. I used the same piece on both the SD housing and the van turbo.

 

Hey thanks JT for the info! I was curious about the results. Sure is nice for you to be the test rabbit! What turbo are you planning for in the future??

 

muahahahahaha my 1.15 truck turbo lives on!

 

Yellow, I don't know about what I'm planning for the future. Developmends and advancements in turbo knowledge for our PSD is happeneing at a rapid rate right now. I'll end up looking at what's out there when it comes time to do the turbo. Plans for the engine are quite big, and include some big oil, bigger injectors, more fuel flow, and other supporting mods. I was originally looking at the QSSB from Wide Open Performance, but they have now come out with a KASB that is supposed to be a little better than the QSSB. Of course Black Widow Diesel, DI Performance, Bean's Diesel, and Wide Open Performance all have some new stuff in the works. It will be 6 months to a year before the upgrade happens, and a lot can change in what's out there by then. The point of me switching to the van turbo was to get me by with what I have now, and also to get me through and then survive as other mods happen, before I have to drop some big bucks for a new turbo.

Kris, I figured you'd be happy with the results. I know you figured we were ok, but I just had to know for sure what was going on. I'm glad I now know, even if it did cost a little bit of $$$.

 

Kris is happy! And since you are getting that new BTS tranny, you will have more $$$ to spend on the turbo right!!

 

Ahhh, yes...that BTS trans definately did free up some funds. However, the turbo will be my last step. Things like big oil and injectors will come first. Got to have the ability to drive a big turbo before it's put on.

 

Well I tried, but it seems you got my last reputation points some time back Jeremy. So I'm going to have to find somebody else to give some to and get back to you. Definately deserved.

 

Thanks Mike. Duly noted.