alternate turbochargers

[aaron1976]

So, I have been wondering if anyone has a different turbo on their truck than what you can get in a kit from ATS, Banks, or Hypermax?

I have been looking at gm4-gm8 turbos which is an IHI. I have an old ATS now and the prevoius owner didn't see the wisdom in having a good intake setup and so it sucked a lot of dirt and has damaged the compressor wheel. Along with needing a new comopressor wheel, I want to change out the turbine wheel and housing so the turbo will spool sooner. I know every one says I will kill my engine with more sooner but I run the truck at 6,400 ft and the air up here is thin. I am dizzy most of the time it is so thin. It may be easier to get a new or better used turbo.

So I wonder if anyone else has done anything different that works better. Looking for a wg turbo if possible or I could put on external wg but the space is tight for that. A non wg would be fine also.

let us know what you are running and how it works, at what RPM it starts making useful pressure and how much boost it builds and such.

 

[sootman73]

the gm turbos are not a very good match for these trucks due to rpm and flow. What kind of boost are you looking for? For higher altitudes i would think you would want more volume not quicker spool times...? quicker spool time would choke on the top end and vice a versa.

i found a T61 compressor with a .8(or close)A/R turbine turbo to be really good for these trucks at the 15-16 psi range but looking at the compressor map it had the perfect slope for a varying boost number while still staying in the best efficiency.

 

[aaron1976]

Hey Ben,

Thanks for the post.

 

[aaron1976]

Ben,

Where did you get your turbo from? I am going to put one of those on my truck.

 

[sootman73]

T61 is the compressor and housing. just find one with a .84 ratio exhuast and i think you'll be okay. me and the guy at work went through a bunch of different maps trying to figure out what wuld be best. there are a bunch on ebay of all different A/Rs. and the higher the A/R the slower it spools and the lower the quicker it will spool. but you will gain or loose on the top end respectively.


just to let you know i have not tried this on my truck as i can't justify the price and effort for this old truck.

 

[sootman73]

of course i dont know how that compressor might change at that altitude.... i'm at only 600 ft so its a big diff

 

[aaron1976]

, I missread some of your post.

I just did a little research on it and I did see that the compressor (T61) has the inducer size of 61mm and like you said it relates the the housing as well. I think it would work fine up here. I know I would loose a little boost but they seem to compensate pretty well for altidude.

 

[sootman73]

here is the map on that turbo. because i'm so close to sealevel i dont have to adjust the scale but you would simply move the graph up and check your numbers.

your standard pressure at 6400ft is .82 atm. ours is 1atm. i looked at the map and you would be out of the best efficiency but yet still within the efficiency safely.

 

[sootman73]

heres a pic of the two altitudes on the T61 turbo map. the red line is at sealevel and the green line is at 6400ft.

the most efficient area of the turbo is the center section of the map and then the efficiency begins to drop off as the boost goes higher. you wont reach the top of the lines. each line starts off at 15psi of boost.

 

[aaron1976]

Ben,

That is awsome. Thanks for the info. I appreciate it.

I like the way it looks. I think I would run with it. Wonder what a T62 would do?

I am on the watch for a t4 t61 turbo with a .8 -.84 turbine.

 

[FordGuy100]

I would say a turbo off of a DT466 would be a nice match

 

[aaron1976]

Does anyone on O.B. run a turbo off a DT466? What make is it? I wonder where it would spool in the RPMS?

 

[FordGuy100]

Yes I believe somebody does. I think he said just revving in neutral results in like 6 psi

 

[Diesel JD]

2 guys here have them at least. 91F2504X4 and RKoch, but neither of them seem to post anymore. RKoch always had interesting stuff to say and it sounded like he had built a few of these systems. You can probably grab one from any year DT466 on ebay or at a medium duty yard for cheaper than a full IDI kit. The downside is your stuck with junk unless you are a good welder or fabricator or know one who will work for free or cheap. If they can build that kind of boost you're going to need studs on a 6.9 and I would highly recommend some sort of boost reference. The only one I know of is the Hypermax smoke puff limiter. That alone might help with some of your excessive EGT problems. What it does is limit fuel delivery until there is enough boost there to keep the smoke at an acceptable level. Correctly adjusted it works great I'm told, incorrectly adjusted it may cut down on performance or flat not work.

 

[aaron1976]

I sent a pm to 91F2504x4 so we will see if he reply's. I may try to pm RKoch as well.

I like the idea of a DT466 turbo. They are wastegated so you could run a wg controled that would open at 10-12 psi. I may go to 14-15 up here at 6400 ft. I run that much now at higher rpms.

I will check out the puff limiter. Sounds like something I could use. My pump is turned up. I just have to limit the fuel by foot now till the boost comes on but it would be nice not to have to do that manually.