Engine/Transmission (1994 - 1998) Ball Bearing Turbos

[MMcCallie]

Twins won't fit so I need to upgrade to a better turbo. I've never been impressed with my HTT HTB2 62/12. Very slow spoolup as I drive around town rarely seeing any boost. Turbo doesn't light until about 10 psi and then doesn't climb super fast like I'd expected. Surging is horrible from roughly 10-27 psi. Surging is worse when towing and often a downshift does not completely eliminate. EGTs are high at all times, climbs to 1,400 in a second and has exceeded 2,200 degrees.



I'm looking for a turbo that will spool and light instantly, won't surge or maybe just very little, will be able to manage EGTs to a safe level, and have durability that I won't have to worry about.



I've read that ball bearing turbos have had major reliability issues in the past several year and that even recently many pickup owners have disliked them. I've read that turbos with dual ball bearing cartridges are the most durable. Also that they often show boost at idle, spool as if driving a gas engine with a supercharger, don't surge, can be shut down hot because they keep spinning after shut down, have a water cooled center section, but that they also tend to run higher EGTs.



I've looked into Turbonetics and Garrett. Does anyone have experience with these turbos? Any recommendations for who I should contact for further guidance? Ball Bearing turbos are extremely expensive but since I'll be swapping into my third turbo, I'd like whatever turbo is next to be my last. Industrial Injection is recommending their SPS 62/12 or Silver 64/14 and not any ball bearing turbo.

 

[TBurow]

will the old turbo be for sale?

 

[MMcCallie]

Definitely.

 

[MShaheen]

i know someone selling thier garret ball bearing turbo. He's gone to a 66. it measures 64/71/13 and is water cooled and comes with all the plumbing.

 

[MMcCallie]

MShaheen, do you know why he's switching to a 66? 64/71/13 sounds like good numbers for air flow and spoolup.

 

[12V Ford]

If you don't like the 65/12, you won't like the ones II suggested for sure. I would give forced inductions a call and see what kind of ball bearing turbos they suggest.

 

[DCreed]

II prolly suggested the 71 & 74 exhaust wheels to stop the surging but they will come with a lag penalty, which you claim is also an issue. IF the 62/12 is a pig you may have a turbine issue or lack of gate sealing/pressure. I would suggest removing the turbo and taking it apart for inspection especially if it has seen 2200*! the gates and or wheel may well be damaged and the housing may have cracks all of which will ruin its efficiency. On the flip side, I will be putting on a Turbonettics 66/12 bb next week and can give feedback then.

 

[DRAG DIESEL]

MMcCallie,



If your anywhere near 6700ft+ what works for folks at lower elevations wont yield the same results for you. You offset surge by being up in elevation, but only by lag. Most guys at altitude are way overfueled and some creative trimming can actualy increase drivablility and make HP go up. 62/12 is a fairly fast turbo, yes a ball bearing will be faster, but their life span is not a great a bushing style charger. You might NEED a bigger charger for you power level, but drivability will suffer at you elevation. Your setup looks good. The 913 can throw down a lot of fuel early. AFC adjustments might go a LONG way.

 

[24V-DSL]

Love my HTB2 62/12 at my 200' elevation. Hate it at 4000+ elevation.

 

[Hammer]

here is my thread on the Garrett GT37R Stage 3 which was on my truck. I sold it when I went larger to a owner who placed it on a 79 Ford conversion truck which is out in the Springfield. OH area. I loved the turbo and the low end spool up was very quick but I could not get it over 500hp which was the reason for the change. It was a great daily driver and performed flawlessly after I fixed the restriction in it.



https://www.turbodieselregister.com...ng-into-garrett-powermax-turbo-kit-2-gen.html



Hope this helps some... Andy

 

[MMcCallie]

Oh, sweet, it will be great to hear from some more first hand experience. And I'd already read that post, definitely helpful. I called Forced Inductions. He said the Garrett turbos are the best turbos money can buy. Price is the same as II's Silver series turbos. He said he's had the same problems I'm having and his last turbo was exactly what I have but that he now runs a Garrett Stage III GT3788R and it has solved those issues. He says it spools 200-300 RPMs sooner, lights at about 10 psi but gets there and climbs from there far quicker than any S300. He claims they have tried just about every High Tech and Industrial Injection turbo since they are dealers.



He agreed the ball bearing turbos had problems but claims they have been worked out as of years ago. The GT3788R has a 64 mm compressor wheel and 72. 5 mm turbine wheel with an exhaust housing comparable to a 14 cm. The models for newer trucks use a V-band clamp and have a built in 90 degree compressor elbow so the boost hose can strap directly to it. Sounds like the exhaust elbow modifications might not have been necessary. Forced Inductions told me the same thing, that they have the 2 bolt design for stock trucks but that the later model Cummins came stock with 4" V-band clamps so if I order the right turbo, that problem should be solved. I need to call Garrett to confirm that information.



Forced Inductions also said the GR3788R is the nicest driving turbo they know of. The guy pulls two race cars on his trailer with a trailer weight of about 15,000 lbs and the hottest he's ever seen his EGTs is 1,500 degrees pulling up a long grade. That's hotter than what i'd like to see. His truck is a stick but he said the boost comes back up far faster than any other turbo. He said he's never been able to get one to surge and has never heard of anyone doing so.



I described my setup and he thinks I could still get 600 HP but that the turbo will be at the end of its compressor map and EGTs will get high. Garrett rates the Stage 3 at 550 HP and 1,100 TQ but on their website states that different fueling can reach different results. I asked the guy how much horsepower the turbo is capable of supporting and he said it flows 72 psi per minute which equates to 720 HP. He's seen as much as 55 psi on his, didn't ask if he adjusted his wastegate. He said I should be fine wastegating at 50 psi.



The ball bearing turbos sound incredible. Supposed to be indestructible with dual ball bearings and no thrust bearing to fail. He said you can blow on it and it will spin, and you can spin the whole turbo over in your hands and the wheels won't move with the turbo. That's how freely they spin.



Only thing that doesn't sound good is that it sounds like it won't flow much more on the top end and might not do much for my EGTs. Then again, the exhaust housing and turbine wheel are slightly larger, though the compressor wheel is smaller. Sounds like under most driving situations the boost will be higher and EGTs lower, but what about the top end? Will maximum EGTs decrease as well? I'm not sure I've got room for a larger intercooler and water injection only does so much.



I imagine Garrett must sell larger wheels and housings to upgrade into but I couldn't stand spoolup being any later. Oh, Forced Inductions also claimed there is only about a 150 RPM difference from the Stage 1 to Stage 3 in spoolup time. That's impressive.

 

[12V Ford]

You could also give Harry at Peak diesel a call and see what he says. Last time I talked to him, he suggested the garret stage 2 (I think), over a gt4202r. He said that would spool fast. Of course I was looking for a fast towing twin setup. That alltitude, it's a killer:-laf. I noticed more lag on mine when I put the 14cm housing on. I think I'm going to put the 12 back on until I build the next set.

 

[Hammer]

I tried and tried to get my GT37R Stage 3 over the 500hp mark and spent hours on the phone with the Eastern Garrett rep about it. With all the dyno runs we made with it the charger was just flat out of gas when it needed to make power to slip over 500 on my 12v. The low end soopl up would plant you in the seat and the sound was sweet,it was just flat out of energy at 2800 and would make no more power above that. At 498hp I felt I had gotten what I could out of it and so did both the shop who built my motor and the local Garrett rep. One thing to keep in mind is that Garrett rates their chargers at the crank and not at the ground for power. My torque at 498 was flatlined at 1200 on the local jet as they do not have the big tq program. It was impressive and fun to drive but wanting more made me sell it and I wished I would have kept it around as a spare to play with,LOL... ..... Andy

 

[MMcCallie]

They rate them at the crank? That sucks. That means that if it is rated to 550 HP it should only dyno around 450 to the ground after parasitic drivetrain loss? That means if I now dyno 600 HP I could only get about what you got and that my EGTs would probably be even higher, right?

I read on competitiondiesel that someone got their truck to dyno 691 HP, 1408 TQ on the Stage 3 Garrett making 42 psi with the wastegate blocked, just hitting 1600 degrees F. at the end of the dyno run. Looking at their compressor map I would think it should support well over 600 HP. May need to go with a larger turbine wheel and exhaust housing.

 

[Hammer]

Yep...

But the truck that did that was a commonrail and the charger was a modified GT37R from Turbo Resource.

 

[MMcCallie]

DCreed, any feedback on your Turbonetics turbo? I've got a Garrett Hybrid Stage 2/3 in and am trying to problem solve. Boost is close to 50 psi but power is severely lacking on the low end. Acts like there's a boost leak but haven't found any leaks.

 

[DCreed]

I got it twinned with a 480 and it seems to work well. surged like heck as a single. it has a T4 foot and external 38mm gate.

 

[MMcCallie]

Yeah, mine is surging far worse than any other turbo I've tried. Can't believe it. How was your boost as a single? Mine is about the same though it shows boost right off idle. But the bottom end has lost tons of power from there, doesn't plant you in the seat at all. Major power loss with the same peak boost. Tons of smoke. I need to check the drive pressure. One good thing is the major drop in EGTs, can barely get over 1,300 degrees. Do you know how close yours was as a single? How is it working now in your combination?

 

[DCreed]

wasnt good as a single, same scenario as you. but as a top twin seems to work well. the penalty for the faster spool is the faster drop in boost when the TC locks or the throttle is lifted.

 

[MMcCallie]

I've talked with High Tech Turbo, Turbo Auto-Resource, and Gillette Diesel and everyone is quite stumped on why this hybrid turbo is performing so strangely. The best conclusion we come close to unanimous on is that the compressor wheel being larger than the exhaust wheel is the most likely cause of the increased surging problem. Perhaps because the difference between the two is so great, the compressor wheel is unable to draw in air as quickly as it should at low RPMs, thereby creating large amounts of excessive black smoke from unburned fuel.

It still baffles all of us that boost starts showing immediately off idle, yet doesn't climb with heavier throttle input from the bottom end. Mismatching of size has led me to overnight yet another turbo. We are hoping a Stage 2 Garrett will be able to spool stronger from off idle.

We know both turbos will be showing boost very early, but our hope is that this smaller turbo will not have the lag of the larger compressor wheel, will spin faster and produce less smoke, and hopefully recoup the hard launches the 62/12 and stock turbos always produced.

It makes sense to me that the turbo could be too large. It has very little power on the bottom end, yet cools so well 1,300 is difficult to achieve on the pyrometer. Amazing to have dropped 600 degrees off my EGTs in just a months time. Amazing to have dropped almost 1,000 degrees in a couple months time. Guess it shows that even these simple mechanical engines can easily be mismatched and setup incorrectly.

Industrial Injection emphasized to me the importance of having a larger turbine wheel to prevent surging. They also said larger turbos will surge worse than smaller ones. With the ball bearing turbos being outside of my experiential knowledge, I was willing to take the advice of the experts. I think I'm learning that perhaps some mechanical generalities of turbo charging are constant, regardless of their technologies and that I should stick with such foundational common sense instead of succumbing to sales talk.

If this new Stage 2 turbo doesn't cure my lousy bottom end response, I think I'll just have to stick with it for a year. High Tech told me they quit dealing with the Garrett turbos because results were too varied and many customers were dissatisfied. Perhaps they are best for electronically tuned engines.

The technology of the Garretts seems so logically superior on paper to my limited understanding of turbo technology. If my EGT improvement is maintained at least below 1,500 unloaded with the Stage 2 and response is at least not decreased, I think I'll stick with it for now. Otherwise, an SPS or Silver 62/12 will probably be my next try, though I've read of many other 12 valves having the same issues of slow spoolup, surging, and high EGTs with those turbos as well. Guess its time to cross my fingers that this Stage 2 solves all of my problems tomorrow.