Turbo Recommendation 98 12V

[Cummins12V98]

Looking for a single turbo for my 98 12V my Son owns now. He had the engine rebuilt by Wizzard Works in Kemp, TX. The owner got about 60 miles on it and noticed low coolant. He had used ARP studs on the head. He is running 18 degrees with custom Piers fuel plate and 4k springs. Trans is a DTT single disk 91%.

Jerry Jardine 4" exhaust with a Pacbrake EB so it's a 3" outlet. PB can go by-by and go 4" inline EB later. 3pc ATS manifold and Banks twin intake. The turbo is a PDR 35. Injectors are DDP Stage 2. It also has a Colt Cam Big Stick. It will be used to tow a heavy gooseneck dump trailer and general driving around DFW, TX. Looking for good all around performance and dependability.

 

[AH64ID]

Ummm...there are other issues if the drive pressure from the stock turbo caused a HG issue, and I’m not aware of any single turbo that can be street driven that needs an o-ringed head. Sounds like an excuse to me.

I wouldn’t o-ring it, that’s not a mod that is daily driver friendly.

 

[Cummins12V98]

Please explain not daily driver friendly on the “O” ringing.

 

[AH64ID]

O-ringed heads don’t like like the duty cycle of daily driven motors, meaning more frequently going they heat-cool-heat, etc. They are not as reliable. Their intent is to create a better seal on a more short term basis.. but the need isn’t there in this case.

There is no good reason to have an o-ringed head on a single turbo truck, or even most twin turbo trucks.

Nothing you have said about the motor, mods, or use points towards an o-ringed head. If the builder is blaming the use of coolant on the stock turbo he is just looking for a way to get your son to pay for his issue, IMO.

 

[BigPapa]

What John said. I thought the same thing reading your original post. With the mods you have listed, he doesn’t even need studs, much less o-rings. Your builder screwed up.

 

[AH64ID]

As for the original question about a turbo, what colt cam is in it?

Based on towing heavy I’d say a smaller than a larger turbo, maybe a hybrid 35/40. He could even have his current turbine housing machined for the 40 wheel and keep the exhaust brake.

 

[Cummins12V98]

As for the original question about a turbo, what colt cam is in it?

Based on towing heavy I’d say a smaller than a larger turbo, maybe a hybrid 35/40. He could even have his current turbine housing machined for the 40 wheel and keep the exhaust brake.

I edited it in, it's a Big Stick.

My logic is the 3" outlet is the BIG killer. The PacBrake with 4" outlet would be nice, would that receive a lot of back pressure?

When I had the truck it did not have the cam. It would hit 40# boost almost instantly. I always had to tow with the pyro and my right foot.

My Son said he spoke to "someone" and they said the O-ringing was not an issue but Fire ring may be? Personally I would have thought studs would have been plenty.

Head and block were completely machined. This guy is very meticulous and does a ton of complete rebuilds on the Cummins engines.

My Son was looking at the PDD Agressor 62, they are on backorder.

 

[AH64ID]

Studs are more than plenty for that build. O-rings are better than fire rings, but neither are needed.

He may build lots of Cummins but it seems something went wrong on this one.

Something like this would be where I’d start looking. https://mopar1973man.com/topic/17344-my-idea-of-the-ultimate-towing-turbo/

I also wouldn’t be scared to keep the 3” exhaust housing.

 

[Cummins12V98]

Edit, builder did NOT blame turbo. That was my Son's assumption.

He is pulling it apart and making it right. Orings I don't know.

Definitely want a 4" outlet and replace EB in 4" also. May be better off with a PacBrake EB that is 4" and leave turbo alone, thoughts???

 

[BigPapa]

I also wouldn’t be scared to keep the 3” exhaust housing.

I agree with John, the 3” exhaust isn’t your problem, either.

Again, with the mods you listed, if the builder did what you said, something either wasn’t done properly, they made a mistake and messed something up causing the new gasket to fail or, the new gasket just failed. Things happen. I’m sure it wasn’t something they purposefully did. I’ve seen even the best techs make a mistake. They’re called come-backs, basically “warranty”.

You said the builder’s making it right and redoing it. Sounds like a reputable builder.

 

[Cummins12V98]

My Son did a lot of research and in person interviews. One thing that impressed me was he didn't finish the install and say come and get it! Owner/builder had been driving it for about 60 miles and noticed coolant low.

 

[AH64ID]

Since the PDR 35 already has a larger compressor wheel I would consider just modifying the turbine side with a HX 40 wheel, and maybe a slightly larger wastegate opening. I probably wouldn’t go with a larger housing since he plans to tow. This will likely improve spool and reduce drive pressure.

Glad to hear the builder is making it right.

 

[Cummins12V98]

He said leak was at #4. Everything looked fine. He already has the head at the Machine Shop.

Yes nice he is making it right.

 

[Cummins12V98]

Shop owner doing the work told my Son he also checked the top of the block and it's also perfect. Must have been a bad head gasket.

 

[GAmes]

I'm constantly amazed by the number of people who think you need to build a race engine for a towing vehicle. A member of another forum I am on installed a Colt Big Stick in his rebuild, a truck used everyday to pull heavy trailers. He says in hindsight he would have installed a stock cam and saved the $400. I would also like to point out that it isn't boost that blows head gaskets. Considering the amount of cylinder pressure created when the fuel ignites, how is another 10 or 15 psi going to affect it?

I use my truck for towing. I have logged nearly 600,000 miles of commercial towing and in addition use the truck for my personal 5th wheel and gooseneck trailers. I installed an exhaust brake when it had less than 3000 miles on it and wouldn't dream of removing it. I'm sure it creates a bit of back pressure compared to having a free flow 4 inch downpipe, but the gain wouldn't be worth the loss.

 

[Cummins12V98]

I'm constantly amazed by the number of people who think you need to build a race engine for a towing vehicle. A member of another forum I am on installed a Colt Big Stick in his rebuild, a truck used everyday to pull heavy trailers. He says in hindsight he would have installed a stock cam and saved the $400. I would also like to point out that it isn't boost that blows head gaskets. Considering the amount of cylinder pressure created when the fuel ignites, how is another 10 or 15 psi going to affect it?

I use my truck for towing. I have logged nearly 600,000 miles of commercial towing and in addition use the truck for my personal 5th wheel and gooseneck trailers. I installed an exhaust brake when it had less than 3000 miles on it and wouldn't dream of removing it. I'm sure it creates a bit of back pressure compared to having a free flow 4 inch downpipe, but the gain wouldn't be worth the loss.

Hey he installed it a few years ago when it was more of an occasional tow and mostly just running around.

When I had it Piers and Bill Fretcher both played with it. PDR35, Piers matched set of 215's, custom plate. 300 RWHP. It ran GOOD.

I said to leave the DAMZ thing alone, oh well.

 

[GAmes]

When I had it Piers and Bill Fretcher both played with it. PDR35, Piers matched set of 215's, custom plate. 300 RWHP. It ran GOOD

That is my set up. PDR HX-35, stock 215 injectors, custom fuel plate. 313 HP at the wheels. I wouldn't be afraid to tow a trailer to AK and leave today with it.

 

[Cummins12V98]

That is my set up. PDR HX-35, stock 215 injectors, custom fuel plate. 313 HP at the wheels. I wouldn't be afraid to tow a trailer to AK and leave today with it.

Always seemed like a good setup. ONLY problem was towing i had plenty of pedal left but had to tow by the pyro.

Maybe I am wrong but have thought going to the 4" PacBrake would allow more air flow???

 

[GAmes]

I'm sure it could, but would it be cost effective?

When towing I go by the boost gauge. After multiple NV4500 failures I found they lasted longer if I didn't over stress them as much. Keeping that habit the G56 has been trouble free for well over 400k miles. At 20 psi of boost climbing up to the Eisenhower the EGT is bumping 1000. At normal elevations it is at about 900. The coolant temp is the real limiting factor, but I think I've solved that with a 4 row Icebox radiator.

 

[Cummins12V98]

It's the vac controlled EB on the truck and unfortunately they are NOT very dependable and like to stick even with proper lubrication.

The truck needs an EB towing the dump trailer. So based on that what would make more sense?