Everybody on here has been telling me that the hx35, even when upgraded, is not as efficient at high boost as an upgraded h1c. Not a bad turbo by any means. Doesnt matter to me, cause I have the hx already, but thats just what Ive come to understand.

 

I've never actually seen a compressor map for any of the Holset compressor wheel/housing combos. However, the HX35 is a good upgrade over the stock, 54mm, non MWE H1C.

It seems to me that the bigger compressor wheels would not be that much more efficient at high boost. They come from bigger engines (6CTA's, etc) as well as a few marine applications I think; it seems their main advantage would be in flow rate, not pressure. For example, our Case 8940 w/6CTA still only runs ~28psi boost, but the flow rate is quite a bit higher than a 6BTA at 28psi. It has a 58mm, 8 blade wheel.

It's an interesting subject; I'd like to see some compressor maps for Holset stuff.

 

HTT told me they had no idea when a StageIII kit might become available, and they were considering eliminating the H1C upgrade stuff altogether due to a lack of parts. So I bought a used HX35/12cmWG.

 

I think that is what I am going to end up doing also. I just have to keep my eyes open. I was thinking ebay but am unsure about buying a turbo from there I don't want to spend alot of money for something that they say is good and get it then find out that it has gobs of shaft play.

 

Watch craigslist and check junk yards. Those places you can check them before buying. I got mine from craigslist.

 

I got to looking around for alternatives to the htt stuff. I came across Gillett Diesel Service, they list a stage II with 60mm wheel, mwe slots, (sounds like htt's stage III). I ordered one for a non-ic truck. $150+shipping and they have them in stock. It might not be the stage IV but at least it's another option and the price is right.

 

That sounds like a great deal.

 

I called Gillett Diesel today about turbo upgrades for my truck and talked to a guy named Rich. He asked me what egt's I'm running at right now and I told him my gauge is post turbo and I don't have an accurate temp. This guy told me that our trucks make the most torque when at our max egt. temp. I didn't argue with him about that because I'm not sure. But then he started to tell me that our trucks could run at 1400 deg's all day long I relized I was talking to the wrong guy. I'm not saying that there products are bad, all I'm saying is if you need to help to make a decision on what upgrade you need talk to a guy named Mark who I think knows whats going on.