My 250+HP CRD build

CIMARRON13 · **Posted:** Thu Jun 26, 2014 9:54 am

The expensive part would be the labor. How many hours have you put into fabrication and modification on this? I'm glad you are figuring out a new option that looks like it's going to work.

diesel_guy86 · **Posted:** Thu Jun 26, 2014 7:05 pm

Most time fabricating was making the water pump inlet flange I didn't need. Timewise its the same as changing the factory turbo, only it takes an extra 15 minutes to put on the adapter. I got rid of the factory steel turbo oil line and put in -4 AN braided line. Cut the drain line so I could use 5/8 hi temp rubber hose instead. If I was swapping a turbo onto a stock Libby, I'd use the 2560 and get the compressor housing that has the same inlet as the factory. This means the factory inlet hose and boost hose stay the same. A new downpipe could be made that would bolt in place. If a kit was made, the new turbo could be swapped in, in the same time it would take to put the factory turbo in. Reflash the computer, take the vacuum actuator out (2 8mm screws) and plug the vacuum line and its done.

bshooter · **Posted:** Fri Jun 27, 2014 12:08 am

Been watching this post for a while and hats off to you…. Good Job…..I like when people are willing to gamble on what their capable of doing.

mass-hole · **Posted:** Fri Jun 27, 2014 1:07 pm

diesel_guy86 wrote:

A guy on here (notpicky) actually designed them and had them made. Its a nice setup and the best part is your manifold doesn't get modified, you can take it back to stock if you wanted.
Yes, it does have a wastegate. I made my own wastegate controller, its really simple and costs like $10. I thought about posting pics as I built it but I was in a time crunch and every second counted. Its just an adjustable pressure relief valve. The more you turn the screw in, the more spring pressure there is and the more boost it takes to over ride it. Google diy boost controller and there's tons of pages of how to do it. I took mine out because I didn't have a heavy enough spring.

So, I get how a wastegate controller works, what I don't get is how you control boost besides the upper limit? In my subaru legacy gt, the wastegate was boost controlled as well but it also had a control solenoid(3 way EBCS) which used vacuum from before the compressor wheel to vary the amount pressure going to the waste gate and keep the turbo controlled. If the EBCS opened, the pressure from the compressor housing would get "sucked" back to the intake and the wastegate would stay shut letting the turbo do as it pleased. If you close the EBCS it would let full compressor pressure hit the wastegate actuator and dump the exhaust. I think the wastegate spring was fairly light so when the EBCS closed it pretty much let the wastegate fully open at most boost levels. The EBCS could vary how much compressor pressure bypassed the wastegate so it was not just an on off thing.

In the case of your build, what keeps the turbo from just spinning to 26psi when you are cruising along on the highway at 2200 rpm? You would think it would just run away, as it starts to take off it adds more boost and then the resulting extra exhaust flow spins it even faster until it gets to 26psi. does it not matter because diesels dont care about AFR? or there is not enough exhaust flow to spin that size turbo that easily at normal cruising rpm?

diesel_guy86 · **Posted:** Fri Jun 27, 2014 7:05 pm

You hit the nail on the head with your second guess, there isn't enough exhaust flow to spin it to 26psi. The wastegate is really pressure relief system, the turbo builds boost until it hits the setpoint. The wastegate opens, exhaust bypasses the turbine wheel, keeping boost maintained. I got my new turbo today from KPA turbos. Talked to Bruce on the phone for an hour and man does he know his stuff. Gonna try talking him into making an exhaust housing to bolt up to our factory manifolds, he's even designing a new vnt turbo that doesn't need electronic or vacuum control. Im gonna be trying one as soon as it comes out.

geordi · **Posted:** Fri Jun 27, 2014 8:26 pm

How could a VNT be accurately controlled if it lacked both vacuum or electronic controls?

diesel_guy86 · **Posted:** Fri Jun 27, 2014 9:15 pm

If I understood him correctly, the actuator is tapped into both the intake manifold (boost reference) and the exhaust manifold (turbo drive pressure aka back pressure) and moves the vanes to keep everything balanced. I was very impressed with his knowledge and go get em attitude. His turbos use ceramic bearings that outlast and perform better than other turbo manufacturers steel bearings. Garrett offers a "ni-resist" turbine housing for heat resistance, his turbos center section and turbine housing come standard in ni-resist (high nickel content alloy), also casts his turbine wheels in inconel 625 (aerospace quality metal, think jet engine) for the most durable turbine wheel you can get.
I'm going to be staying in contact with him and possibly someday be able to produce a ball bearing vnt turbo option for the crd, WITH the same bolt pattern as factory.

thermorex · **Posted:** Fri Jun 27, 2014 11:27 pm

That would be nice. I'm also interested how much pressure his vnt turbo Can build and if there is any way to manually adjust it, or does he preset the turbo.

Good progress and research so far!

diesel_guy86 · **Posted:** Sat Jun 28, 2014 12:06 am

I'm not sure, he said he would have to pretty much size it to what I needed, so it would probably be preset.
In other news I got the new turbo installed and well, its a lil better down low in the revs, but up high egts are killing me. The last run I pegged the 1600° gauge. I'm wondering if the bearings might have to loosen up a bit, but regardless I think I'm gonna downsize to the 2860's lil sister, the 2560. At this point I think I can do a turbo swap in about 1.5 hours, blindfolded, with my hands behind my back, upside down. But hey, how often does one get it right the first time?

thermorex · **Posted:** Sat Jun 28, 2014 12:49 am

Woo-hoo, Should've had somebody to tape the red glow of your manifold. How much boost you had? I wonder if the fuel quantity is right for this turbo, you may need to become a computer geek also, so you start adjusting it. A Dino would help a lot if you or a friend have one.

diesel_guy86 · **Posted:** Sat Jun 28, 2014 9:14 am

The first time I ran it I had 21/22 psi, shut it down and drove it again 30 mins later and hit 27psi. Kinda seems like the bearings might be loosening up some. its gonna take some experimenting to find the right combo of fuel/air. Might try to back the fuel off a bit first, see how it does on that and then change turbos.
The 1600 was very brief, and happened after I let off at 1400, the lack of boost when I let off must of thrown the egts up another couple hundred. Love these peak recall gauges. I really want to install a drive pressure gauge next so I can measure how much pressure it takes to make the boost. Obviously you want 1:1 boost to drive pressure. Too much drive pressure means your getting exhaust gas in with the cylinder. More boost than drive keeps the exhaust flushed out of the cylinders and keeps egts down. Its very often overlooked but really helps in making an efficient turbo system.

CIMARRON13 · **Posted:** Sat Jun 28, 2014 11:01 am

Keep up the good work. Hopefully you find the combo that works. It would be great for the community to have a replacement that is easy to do and easy on the wallet. I haven't had any problems yet with my turbo but it's always in the back of my mind.

diesel_guy86 · **Posted:** Sat Jun 28, 2014 9:30 pm

Think I had a brain fart, I unplugged the wastegate to keep it from opening so I could get higher boost. Both turbos have hit 26/27 psi and then bled off. I'm thinking the exhaust is forcing the wastegate open at the actual gate. Gonna put some vice grips on the wastegate rod to keep it from opening at all and see if it makes a difference. This would explain why boost holds steady once it hits 26psi.

geordi · **Posted:** Sat Jun 28, 2014 10:56 pm

Bypassing the wastegate entirely and trying to force higher boost than 26psi...

Either your intake will lift off, or the pistons will Exit Stage Left taking the bottom route out. Should be entertaining either way! Truly, you are either filthy rich or batcrap loco. I'm not sure which, and I'm also staggered that your engine has survived so far.

I can't wait to see what you do next. Keep pushing the envelope, eh? :POPCORN:

diesel_guy86 · **Posted:** Sat Jun 28, 2014 11:25 pm

Lol, more like bats*** crazy. I'm just trying to get enough boost to maintain 1200°egt. Right now it hits 26psi and then leaks down to 21/22 psi and that's when the egts skyrocket. I think the reason the bottom end is still there is because the ball bearing turbo takes such less oil. Now the bottom end has all the oil it needs, my theory at least. Not really going for all out performance either, just trying to keep it all in check first.

geordi · **Posted:** Sun Jun 29, 2014 1:20 am

Is your EGT being measured pre- or post-turbo?

I had my EGT probe in the mouth of the turbo, and I seem to remember it only hit around 1200 when I was sticking my foot in it or was towing. Are your numbers during steady-state or when you are feeling the floor through the go-pedal?

diesel_guy86 · **Posted:** Sun Jun 29, 2014 8:20 am

Pre turbo in the same spot as you, right at the inlet. Those high egts are at full throttle giving it all she's got. When cruising temps seem to be around 800° or so.

GreenDieselEngineering · **Joined:** Sun Jun 07, 2009 5:10 pm **Posts:** 1111

I do not think you are pushing enough air for the level of fuel injection. We need to dial it back a bit. 1380 F is the max exhaust temp you want based on the thermocouple position in your CRD. Running above this can be detrimental to the engine and turbo.

diesel_guy86 · **Posted:** Sun Jun 29, 2014 11:03 am

Kieth, I agree with you 100%. In my late-night thoughts I was guessing pulling the fuel back, 10%? My honed injectors are spraying the same quantity of fuel as stock, just a whole lot quicker. I'm gonna try to lock the wastegate down good first to eliminate any leak spots. If boost climbs past 26psi I'm good, if it shoots past 30 I need to get a higher rated wastegate actuator.
Also do you advance the timing at all on these tunes? I know I hear a lot of truck guys talking about timing. Didn't know if advancing the timing any more would maybe help the egts?

GreenDieselEngineering · **Joined:** Sun Jun 07, 2009 5:10 pm **Posts:** 1111

Yes the main injection timing is advanced with the base tunes, yours is set the same and I would not recommend further advance.

With the honed injectors we know more fuel is flowing with a shorter duration, so more advance is not the way to go. What we do not know is the atomization of the fuel spray as it enters the chamber due to higher flowing nozzles. The fuel could be hitting the bowl more and not mixing in the same manner as a stock nozzle.

My 250+HP CRD build

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