Cummins 12 Valve turbo on Ford IDI

[aaron1976]

Wondering if anybody out there has tried a different turbo setup (other than AtS or Banks) on their IDI 6.9 or 7.3? I was looking on eBay today as I saw a turbo off a Cummins 12 valve. Not sure if it is big enough for the 6.9. I hate the late spool of my non wastegated ATS. It doesn't make boost until around 2000 rpms. I would like boost at 1200 rpms. My turbo probably needs a rebuild.

I would also like to put an intercooler on a setup like this. Would have to keep the boost to 10 PSI or so.

Anyone have any thoughts? Any experiences?

Thanks,

Aaron

 

[Clydesdale]

Complete Hi Jack, but how do you like the 37 HMMV tires.... I have 3, waiting for 4 and 5 to run them.

 

[kas83]

You're going to tear that motor up with any real amount of boost at that low of RPM. The cylinder pressures will wreak major havoc on headgaskets, wrist pins and so forth.

There are some that have tried the HX35/H1C style turbo's, and some have good luck, others not so much. They are going to be gated in stock form around 16 psi, and I don't know how you'd lower that setting. And trust me, it's plenty big enough and capable of the airflow for a 6.9.

What do you mean by no boost til 2000 rpms? O psi until you're at 2000, or 2-3 then climbs faster after 2000? Mine is somewhat lazy, but I can get a couple psi at 1700 or so, and then it will steadily climb from there. Non-gated turbos for these trucks were never meant to be super quick spooling.

 

[aaron1976]

I love the Humvee tires. I had the 36" bias tires before and they were terrible. The 37s are radial and track straight. I found a wheel without a lot of off set so the steering and axle don't have to stress too much. The tires do well in the snow and ice as well. I think you will like them.

They do measure 37" unlike a lot of tires that aren't as tall as they are stated to be.

 

[aaron1976]

I do get 2-3 psi at around 1650 rpm or so. And it does climb steadily as the rpms increase and at the moment with the fuel pump setup as it is I get a peak of about 7 psi.

10 PSI at 1200 rpm would kill this engine? I suppose you are right with the high compression ratio of the IDI engines but I didn't think that the RPM would make a difference.

I think an external waste gate would be the way to go. If I were to put in an intercooler I could install an external wg inline some where.

 

[kas83]

An external wastegate goes in the exhaust plumbing, not the charge air plumbing. The rpm being low will make the internals more susceptible to the cylinder pressures, as it takes longer to get thru the cycle.

As it sits right now, your ATS seems to be doing what it's supposed to, and was designed for.

 

[redneckaggie]

http://www.oilburners.net/forums/showthread.php?t=36316&page=2

that is the ideas that i have so far but the prob is that i dont have the money to make it work lol.

 

[fx4wannabe]

Being that these engines were never really designed to have a turbo, i think its cool that they take what they do. I remember when I started looking into turbos for these and I was hearing these 10psi numbers and thinking why bother. I still kinda think they are more trouble than they are worth. My 93 N/A felt like it pulled harder than this 94 turbo and it had twice the miles.

 

[fx4wannabe]

I love the Humvee tires. I had the 36" bias tires before and they were terrible. The 37s are radial and track straight. I found a wheel without a lot of off set so the steering and axle don't have to stress too much. The tires do well in the snow and ice as well. I think you will like them.

They do measure 37" unlike a lot of tires that aren't as tall as they are stated to be.

How much lift do you have to fit them on there?

 

[Clydesdale]

Probably not much, 35's go right on an OBS, 92-96 requires bumper shim or trim, an 87-91 250 will take 35's with nuthin done.. there is a Centurion on my board (well not mine.. but you get waht I meant) that is running 38's on his 87-91 truck, no lift.

If I had mine mounted, I would show you a pic, but have not swapped them yet, seems silly to swap three.

All I have for lift is a SuperDuty leveling spring pack.

 

[hesutton]

I love the Humvee tires. I had the 36" bias tires before and they were terrible. The 37s are radial and track straight. I found a wheel without a lot of off set so the steering and axle don't have to stress too much. The tires do well in the snow and ice as well. I think you will like them.

They do measure 37" unlike a lot of tires that aren't as tall as they are stated to be.

I run them as well. At least for the time being. The guy I would get them from was a big military supplus junker. He had semi trailers full of them. He passed away last year and now once I use them up, I won't be able to get them any more.

Where are you getting yours? How much per tire?

Heath

 

[typ4]

Being that these engines were never really designed to have a turbo, i think its cool that they take what they do. I remember when I started looking into turbos for these and I was hearing these 10psi numbers and thinking why bother. I still kinda think they are more trouble than they are worth. My 93 N/A felt like it pulled harder than this 94 turbo and it had twice the miles.

If it has the original turbo pump on it it may be a pig. They need some tweaking to get optimum performance.

 

[dyoung14]

If it has the original turbo pump on it it may be a pig. They need some tweaking to get optimum performance.

i would gladly trade me non turbo pump for a good turbo pump but it would have to be a good one low miles not junk cause mine is a low mile rebuild

 

[aaron1976]

I have a 4 inch lift on it. I have aluminum running boards the full length of the cab and back to the rear tires. The tires rub just a bit at times when I am turning. Other than that all is well.

I get these tires from a guy in Wisconsin. I found him on eBay. and I got a set of 4 for $400 plus $170 shipping, which I thought was pretty cheap for shipping.

I think I will go with a moose pump from our pump guy here on Oil Burners. I would like to see that that does for the truck.

At what rpm do the waste gated ATS or Banks turbos start to spool up? I have heard that they start to make boost sooner.

 

[cetanefreek]

the gated turbos will spool sooner simply because the turbine housings are smaller, there are two ways to keep a turbo from overdriving or overboosting, the first way was to put a turbine housing on it that was so big that your engine couldn't move enough air to overdrive/overboost, the second way is to put a wastegate on a smaller housing, that way you have the tighter housing that will spool sooner and be in the map sooner and once you reach a certain amount of boost the wastegate will open and allow exhaust to bypass the turbocharger preventing it from spooling into parts-breaking territory.

does all of that make sense? I've been drinking.