Nathan S

Just as an update, I received everything in a timely manner from CPP. After reading this thread I sent them a couple emails asking about my order, got replies within a couple hours. An employee named Jessica also called me to make sure that I didn’t have any further questions. I hope they have seen threads like this and are making improvements. Like I said before, I don’t use just one vendor, and have had good experiences with all of them I have used aside from Calibrated Power in Illinois.

It’s interesting how people can have such different experiences with them. I’m not loyal to any diesel shop in particular, and have spent several thousand dollars with CPP in the past. Just the other day I ordered a few parts from them. Got an order confirmation within minutes, shipping confirmation for both things came yesterday as I placed the order on Sunday. XPD has always been great to deal with, as has Diesel Power Products out of Washington. DAP is another shop I’ve purchased from and had good luck. It’s too bad you had such a bad experience.

Do you think the out of balance condition would still cause the rub even with the shaft vertical on the bench and basically no centrifugal force on the shaft? It feels more like it’s out of round to me, just because the rub isn’t consistent all the way around the housing.

Thank you. I will keep that in mind for when the turbo is either repaired or if I go the compound route. I need to talk to calibrated power before I make a decision on what the next setup will be. I feel like the mechanical problems with the turbo are what was causing the majority of the issues. The rubbing issue will only get worse as the turbo gets hotter, then making it contact those places in the housing 100,000 times a minute while it’s as spooled as it could get probably causes a lot of drag on the rotating elements.

Well I got the boost elbow put in this morning. I bottomed the screw out so the wastegate is essentially blocked. I ran the truck up a hill we use for bench marking in the area, about a 6% grade that’s about two miles long. The egt in 5th gear was 1300+ with the truck empty. Just accelerating in 4th gear to get back up to speed between 1500 and 2200 rpm the egt got to 1100. I’m gonna put the other turbo on and see what it does. When I had the intake tube off to put the boost elbow in, I noticed the compressor spins much easier one direction than the other. The blades should slap the air similar to a pump, correct? Spinning in this direction it would stop before a full rotation. It would spin about 2.5 rotations the other direction. Edit: Got the turbos swapped out this afternoon. There is a definite rub in the stealth 64 with it on the bench. There are a couple of spots you can actually hear the metal to metal contact and feel either the compressor or turbine rubbing. I am gonna talk to calibrated power again before I pull it apart to see what it is. Egt up the same hill with the same tune, just stock turbo with a wicked wheel and a banks quick spool housing was 1050 egt up the same hill as earlier today.

I haven’t driven the truck on the highway but it is much more responsive in town those changes. Thanks for the tips and the clarification on how the scaling works.

I paid 11,000 for mine in 2008 with 68,000 miles on it.

I browse eBay for second gens a couple times a month, seems like people want more for some of the trucks than what they cost new. Don’t get me wrong, I’ve really enjoyed having mine and will for years to come but I can’t see how people can ask 25-30k for a second gen.

That’s the way I understand it to work, but with the scaling set to 50% I’m only going to see 2.5 degrees of that total 5 degrees correct? I did make the changes suggested by Silverwolf2691 and the truck seems much happier. Still waiting for the boost elbow to arrive, and I haven’t pulled a trailer with it yet but I will this weekend.

Thank you, I will make those changes and go give it a try tomorrow and let you know how it works.

Max pump stretch: 1600 TPS max: 100% TPS min: 20% Min Pump Tap %: 0% Pump Low Boost Scale: 10% Boost Scaling: 35 psi Max Load Timing Offset: 2.0* Low Boost Timing Reduct: 2.0* Timing Reduction Scaling: 100% Light Throttle Advance: 1.5* Light Throttle Load Limit: 30% 1500 RPM: 14.0 2000 RPM: 18.0 2500 RPM: 22.0 3000 RPM: 26.0 Max: 27.5 0 Psi: 85 1 Psi: 87 2 Psi: 89 3 Psi: 91 4 Psi: 93 5 Psi: 95 6 Psi: 97 7 Psi: 100 8 Psi: 103 9 Psi: 106 10 Psi: 109 11 Psi: 112 12 Psi: 115 13 Psi: 118 14 Psi: 121 15 Psi: 124 16 Psi: 127 18 Psi: 130 20 Psi: 133 22 Psi: 136 24 Psi: 139 26 Psi: 142 28 Psi: 145 30+ Psi: 148 That’s my current “daily tune”. I did download a tow tune from here and it seems to perform the same. Could running too little fuel cause the egt issues because the engine isn’t able to drive the turbo sufficiently?

After seeing that I sure wish I would have asked around on here before making the decision on the Stealth 64. Hopefully I can get this turbo to work how I expected it to from the beginning.

I use the truck to haul a water tank, tow my camper, and daily drive. Towing performance without having to stare at the pyrometer is my main goal. The Jacobs brake replaces the 5 bolt flange adapter that is outlet of the hx35, it’s not a v band or similar connection like an inline brake.

I’m certain this one is the 9cm housing, it looks tiny compared to the other turbo. I did find that turbo lab of America makes a 67mm turbine upgrade for the hx35 with a new housing I am going to speak with them about it to see if it would work for my application. With the waste gate line pinched off completely I could only make about 28 pounds of boost today on my way home from work. The egt seemed about the same, but it’s hard to keep track of so many things at once plus drive the truck.

I did block line from the compressor cover to the waste gate actuator and on a small pull in 4th gear I saw about 30 psi, and the truck felt like it had a lot more power. The egt seemed slightly lower on my way to work about 30 miles from home. I wasn’t able to push it very hard because of the roads being wet as it has been raining all day. I will put the camper on it this weekend and see how it acts.

I’ve got an adjustable boost elbow on the way, I’ll try that before taking it off the truck. Tomorrow I can try crimping the line off to see if that makes any difference. When I was checking for boost leaks I made sure to watch the actuator for the waste gate and couldn’t see it move with 25 psi on the piping.

Max boost pressure I can see is 25psi. It stops dead at 25psi and will not climb higher. I’ve thought of adjusting the waste gate to see if it was opening early and contributing to the problem by not allowing the turbo to spool properly. The 11 blade compressor is very different sounding from the wicked wheel 2 and factory hx35 compressor, it’s difficult to describe but it just sounds like a giant vacuum cleaner under the hood. The day with the rzr on the truck was when I knew it was time to make a change. We are getting in to the best camping season here and worrying about how the truck is going to do is the last thing I want to have on my mind.

I talked with Lenny at Diesel Auto Power about it and he suggested trying an external waste gate between the turbo and the manifold. Does anyone have any experience with running an external waste gate? I saw that DPS makes an exhaust manifold with a waste gate flange built in and I’m sure stainless diesel does as well. Thanks again guys.

I will do some research on turbo builders and see what I can find. I really don’t want to give up the exhaust brake that mounts to the turbo. Thank you for your help.

Is there a possibility of having a 12 cm housing machined to fit the larger turbine wheel?

The 1350 was in 4th gear, just as I was going to shift to 5th around 2300 rpm. Pulling the grade with the rzr on the back was 4th gear, overdrive off 2200 rpm. My transmission is a 5 speed, that’s why I went with the gear vendors. It helps to bridge the gap between 3rd and 4th. With the overdrive engaged in 4th gear, the ratio is so close to 5th direct that it’s unnoticeable, but the transmission runs 50 degrees cooler while towing the camper. I am constantly watching the pyrometer while driving, loaded or not. I did order a couple of gaskets to put the stock turbo back on and see what the truck acts like with the larger injectors and quadzilla.

Last fall I “upgraded” the stock hx35 on my truck to a Calibrated Power Stealth 64 Hx35. This turbo is the same basic frame as a stock hx35 so I can still use my Jacobs exhaust brake. Calibrated power makes their own 11 blade billet compressor, compressor cover. They also make their own turbine wheel which is larger to match the larger compressor wheel, and use a 9cm turbine housing. I think this tight turbine housing is what is causing my issues. I have been battling egt problems with the truck since I put the turbo on. I’ve upgraded injectors after finding posts discussing the effects of too small of an injector with out enough fuel causing high egts. I have updated the old Edge JWA to a Quadzilla to be able to custom tune and have spent the last 6 months trying to get the egt back to where it was with the stock turbo and 75 horsepower injectors. Accelerating on the highway, at less than half throttle I can see 1350 on the egt pretty easily, with the truck empty. I sometimes carry my rzr side by side on the back of the truck on the flatbed, and with it on the truck, pulling a relatively large grade in northwest Colorado I struggled to keep the temps below 1300. With the old setup I would barely break 1200 with my 10,000 pound fifth wheel on the same grade. You could say I’m less that impressed with the turbo. I have been all over the truck searching for boost leaks, change every seal, gasket and o ring that could be causing a boost leak. I really feel that the increased compressor flow with the tighter exhaust housing is what is causing my problems. Does anyone know if I could buy a stock housing and have a company bore the housing out to accept the larger turbine? I’ve talked with Calibrated power about this and they told me they do not offer any other housing for this application.

I will build a new tune and start at 13* and move up in 5* increments, and compare to the current tune that starts at 15*. Am I correct in my understanding of what the low boost timing reduct and timing reduction scaling are doing? The low boost reduct is the number of degrees of timing the quad will pull from the tune at high engine load and low boost pressure. The timing reduct scaling is the % value of the low boost reduction based on load, 50% of 2* at 50% would be 1*, right? The truck really felt as if it was pulling too much timing in the lower gears and then bringing it back all of a sudden when the engine load decreased. Do you think that the somewhat aggressive timing curve is what lead to the head gasket failure? I really don’t mean to hijack the thread, just want to make sure I’m understanding correctly so I don’t give bad advise.

The first tune I built, I started at 14* and increased by 3* through the range. I had more issues with the truck being doggy and having a very prominent stumble as throttle position would change with rpm. I would see timing as low as 11 degrees as indicated by the quad. This was in 2nd and 3rd gear where load would be high, rpm low, and boost low. In trying to eliminate the stumble, I set the timing reduction scaling to 40%, and the low psi timing reduction to just .5*. Once the load would come down as I reached the shift point, there was an obvious audible difference in the engine tone. You have referred to the truck basically sounding as if it turns off when there isn’t enough timing. This is what my truck was doing. It would just fall on its face and buck. The current tune is the best I have had it yet. Timing reduct is set to 2.0* and the reduction scaling is at 100%, so at high load, low rpm and low boost situations the timing is reduced to near the 13* you are recommending. It’s much smoother without a trailer or load on the back, and lights the turbo quickly. In 4th gear, it will make 10 pounds of boost by 1600 rpm at only 50% throttle. By starting at 13* then increasing by 5.5* every step, the 3000 rpm and max timing sliders will just be maxed out, correct?

What are the current settings for each slider in your tune? Im not sure if modifications to your truck, but mine starts out at 15.5* and steps up by 4* on each slider with the max timing being set at 26.5*. The truck seems pretty happy with these settings. There are more parameters that will effect how the trucks runs concerning timing that don’t involve the rpm max timing parameters. It’s been a couple months of reading, studying, and trying different things to see how the truck reacts. It does take time but it’s absolutely worth it in the end. I can’t believe how well mannered my truck is with a somewhat large turbo and pretty good sized injectors.