This is The Bomb ... with Turbo!

#1

Galen's SD eye candy!

#2

The facilities . . . the resources . . . the knowledge . . . the skill . . . the artistic eye . . . I want to be Galen!

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How are you going to bleed the IP? I couldn't bear to spill fuel on that!

#3

WOW!

And they WILL be available to the limited few who send their deposit in real quick, right?

Couple of questions though- is the compression still at 22/1, how much boost, and an intercooler is in the plans, yes?

Color me green,

Dave

#4

This is going in the middle of the living room, right? On a chrome-plated stand? To be worshipped daily, with fragrant dishes of #2 and Powerservice placed on the floor in front of it?

But now for a serious question--when turbocharging most diesel engines, the output of the turbo feeds directly into the intake. On this engine, which has a throttle plate like a gas motor, are you planning on using a blow-off valve (or BOV)? I know on gasser motors the ricers like to use one to dump boost pressure when the throttle plate is suddenly closed (I think because they like the sound of it more than anything). I don't know how necessary a BOV is, especially for single-digit boost pressures that I suspect you will be running.

Must . . . worship . . . engine . . . . . . must . . . bow . . . down . . .

#5

You guys crack me up. I'm glad you approve. But it wouldn't have looked as good if Phil hadn't come over and unwittingly got my gears turning so that I pulled the whole thing out instead of doing an in-frame (it's been sitting a while and I forgot that my trans was bad).

Before I go any further, I should say that I put the turbo on in '94, so this is just the latest incarnation. Unfortunately I didn't take any early pictures, but Phil has posted the first layout photo HERE.

I debated on whether to lower the compression. I have a Cummins that regularly runs at 30 lbs boost and I regret that I lowered the compression on the last rebuild because I lost a lot of mileage. I figured that since
1.) years of 7 lb boost was not even detectable on the pistons,
2.) I'll never be on the boost more than a matter of seconds,
3.) the pistons are coated,
4.) and I'd really like to keep mileage as high as possible,
I'd leave the compression alone. If I have to, I'll retard the timing instead.

Strangely, the turbo made 7 lbs without turning the pump up, which I attribute to removal of the altitude compensator and the EGR. It ran noticeably better. I'm going to see how high we can go this time.

I used the wrong oil rings when I rebuilt the motor once and after a year or so it started to burn oil. Planning to pull things apart anyway, I quit changing oil and just kept adding, so things started really going downhill. About six months before I parked it I put the intercooler on, which unsurprisingly had no effect, and for which I have no before or after values that I can provide. As Jim Stafford said, Ain't much pride when yer trapped inside a slowly sinkin' ship.

Originally I had the throttle body (TB) before the turbo, which I learned wasn't the best. Most turbos aren't made with seals on the shaft but rely on air and exhaust pressure to keep the oil where it belongs. Under idling conditions the high vacuum would pull oil into the intake, and by the time the intercooler was added the turbo was so worn from bad oil that the intercooler trapped lots of black ink. Oily mess.

I was trying to figure out how to manualize the IP when Ben pointed out to me that there was an easier way. Somehow it had escaped me that the TB could go after the turbo just as well, so that's what we're going to do now. I'm hoping that the air volume between the turbo and the TB in the tubing and intercooler will be sufficient to cushion the surge and a BOV (blow off valve) won't be needed, however, I have one picked out just in case.

And just so you won't think it's all sugar and no vitamins, the cam is reground with almost 20% more lift, lifters resurfaced. I ceramic coated the piston tops, the valve heads, the exhaust ports, and the head surface, and teflon coated all the bearings, the cam, the lifters, the valves stems and springs, and the piston skirts. New liners and injectors of course.

Talk about getting out of control.

#6

KC-

Nice work! Sorry, but more questions. Inquiring minds NEED to know....

What turbo did you use, and is the exaust manifold modified cast iron, or fabricated tubular?

I couldn't tell from the photo, all that chrome and bright paint...

Dave

#7

Knucklehead wrote:SNIP- Strangely, the turbo made 7 lbs without turning the pump up, which I attribute to removal of the altitude compensator and the EGR. It ran noticeably better. -SNIP

The altitude compensator could not affect boost pressure because all it does is make a very small adjustment to the fuel control lever position when changing altitude.

A correctly functioning EGR would bleed off boost pressure to the exhaust manifold anytime (a)the EGR was cycling open with (b)intake manifold pressure exceeding exhaust sytem backpressure before the turbine.

#8

throttle body after the turbo is for a low boost option to help with drivability.I would normally think that the governor would not like being boost pressurised.you should steal parts from the SD33T.electronic controled LPG on boost is becoming more common.

All the kits I have seen did not use this option,and used a suck through type turbo.i have seen an altitude compensator that attached as part of the goveror housing on the rear that limited the rack travel when not on boost.

VE pumps used on japanese engines and the SD25 is the easy option these come with boost compensation options..isuzu 4BD1 has similar fitting manual operated IP option with many tuning configorations. Toyota has a denso branded pump that can be grafted in and the mitubishi oi looked at recently operate the same but are mounted on the left side so they may not have linkage clearance.

#9

What turbo did you use, and is the exaust manifold modified cast iron, or fabricated tubular?

Despite the spacious appearance underhood, there is not much room to put the turbo in any position but one, and that is about two inches out from the existing manifold, exhaust outlet at dead center. I modified the stock manifold as a prototype but it worked so well I have kept it. I feel there is very little to be gained by trying to fabricate a header. I've done some tests in this area with a couple of high horsepower Cummins and find various restrictions did not have any detectable effect. Cast iron is extremely easy to weld with nickel rod and very strong, so modifying the stock one is the best bet. Please click HERE to see a photo of the cut exhaust manifold before polishing.

Mitsubishi TC04 from a 1600cc Dodge Colt, 1979 I believe. The TC04, 05, 06 are all hard to come by now, but still easy and cheap to rebuild. There are newer turbos that are made with seals for draw through gas applications. One of these would work well in a system like I setup originally but were uncommon when I did it, and are not cheap now. If you do find one in a pile it will be expensive to rebuild, so you have to pick your tradeoff.

The altitude compensator could not affect boost pressure because all it does is make a very small adjustment to the fuel control lever position when changing altitude.

Since Phoenix is at 1000+ ft the altitude compensator was holding the pump back at least some infinitesimile amout. With it off, the IP thinks it's at sea level now, giving more fuel, yielding more exhaust, hence boost. I don't know how much before, after, here or there, but the point is that the potential is there in the engine even without touching the smoke screw.

I would normally think that the governor would not like being boost pressurised.

The governor does not work from vacuum, it works from the pressure differential across the TB. Just imagine driving your SD22 for a cool refreshing drive down to somehwere way below sea level where the atmospheric pressure was twice as much, say..., Hell. At idle, the diaphragm sees the same pressure differential between the control side and the vent side as it does at 12,000 up in the Andes. At WOT the vent side will be equal to the control side, allowing the spring to push the rack all the way open. Turbocharged it is the same with the vent plumbed after the turbo. As the French chef said, No diference! Of course, this is theory. We will see how well it works in practice. If it is not satisfactory, and I am unable to get a manual control from an industrial Diesel Kiki pump, it will be easier to modify the one I have than to get an entirely different pump and make it fit.

#10

Knucklehead wrote:SNIP-
The altitude compensator could not affect boost pressure because all it does is make a very small adjustment to the fuel control lever position when changing altitude.
Since Phoenix is at 1000+ ft the altitude compensator was holding the pump back at least some infinitesimile amout. With it off, the IP thinks it's at sea level now, giving more fuel, yielding more exhaust, hence boost. I don't know how much before, after, here or there, but the point is that the potential is there in the engine even without touching the smoke screw.-SNIP

Not necessarily, Galen.

The altitude compensator is adjustable in two ways ... initial contact with fuel control lever and total travel.

With the altitude compensator not contacting the fuel control lever (or removed from the IP), that only means fuel control lever is now against the "smoke setscrew" ... which could easily be optimized for any altitude.

Altitude Compensator
Smoke Setscrew

#11

That is completely correct. But I know that mine was more than just making contact because when I first got the truck the tip was worn significantly and I built it back up and adjusted it correctly (my understanding of what it did way back then was nil).

I had actually thought that I might readjust the altitude compensator and put it back on, but... I hate clutter, and on the rare occasion that I drive up north I can just as easily back off the pedal when the pyrometer tells me that I'm running out of air. But you can only do that if you have a pyrometer.

#12

Knucklehead,

If you don't mine what did the ceramic and teflon coatings set you back?

Carey

#13

Great pictures and they are the best as of yet to this awesome project. Every time I see a pic of this custom SD22-T I myself feel like doing the same project and of course with an SD2x engine. Galen, that should be a really nice sounding truck going down the road. Will you get a considerable turbo whistle like most big trucks do? And did you run a front mount intercooler? Keep up the great work man.

Salvy

#14

Here is the website for the company I used, HPC:

http://www.hpcoatings.com/services/pricelist.aspx

There are other companies. The last time I had pistons done was about 10 years ago by a company called Lorn Technical Coatings, which is now defunct. Use a reputable company, but don't be taken by claims such as, "We are the original developers!" As if you should have a paint job done only by the original developer of paint.

The one thing I hadn't intended to coat was the valve springs, but the guy there swore that (as well as tests I read) the springs would stay cooler and last much longer. Since the old springs were all weaker and shorter, and since the new springs were US$62, I figured for $18 more, what the heck? I'm using the old springs for break in though. He talked me out of coating other parts, so I don't think it was just a sales pitch.

Turbo whine is caused by air at the corners of the impeller. There are two ways used to stop whine to satisfy the conservative, neither of which affect performance: Round the corners, or place a venturi like shape in the turbo intake to deflect air away from the corners. I love the whine, and once, when someone got in my truck for the first time and we started out, they told me to pull over quick because they heard a siren. I don't think it is that bad, but it IS unmistakable.

I ran the intercooler on the fender as is seen in the photo. I didn't get to do any tests or take any readings. In the future I will be doing extensive testing. 'Cause it's fun to know!

DanielB · #15

First off, good job on that engine. Did you get it into a vehicle yet? I looked around the forum a bit, and this seems to be the only thread where someone has put a turbo on a SD22. Do you by any chance know about the possibility of using a turbo from an older VW? My dad has an 87 VW Golf with a blown turbo powered deisel engine, and I was wondering if I could steal the turbo off it for my SD25. Did you notice a big increase in power with the turbo on your engine?

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This is The Bomb ... with Turbo!

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