Changing Stacks on a 60s detroit

It doesn't help with spooling. All it does is has a valve that is set to open at a certain pressure. When this valve opens, the turbo stops building additional boost. Disabling the wastegate will cause overboosting. Too much pressure is bad juju. Spooling lag is determined by the size of the impeller blades and the exhaust pressure of the engine. Pull is simply an aspect of torque, which is determined by how much PSI is being produced. Turbos survived because they were built in a manner that limited the maximum amount of pressure the compressor could produce. Now a days, turbos are variable. Boost controllers simply allow you to adjust the open point of the wastegate.

I know this from building turbocharged tuner cars in my Marine Corps days.

 

Really? I will pay you a few bucks if you can find the waste gate on a Borg Warner 171702 turbo. Matter of fact, I would be willing to bet that Borg Warner themselves would be willing to pay up if you could show them where the waste gate is on their turbo. No... all turbos do not have a waste gate. Some have a waste gate, some are veritable geometry turbos, and some are traditional turbos. True, all the DDEC IV engines come with a waste gate turbo, but that is the point I was making.... you can replace it with a non waste gate turbo. Here is the BW turbo I was mentioning.....

http://areadieselstore.com/171702.aspx

http://www.turbodriven.com/files/pdf/S400SX4-1.pdf

 

Hmm haven't seen a modern turbo that has no wastegate externally or an internal equivalant. Learn something new every day, I guess. I fail to see the point. It's basically totally nonadjustable like it is, right? That's why they got away from the traditional styles.

 

Ah, ok. I did some reading. The BorgWarner there is designed for applications were the vehicle will not have the power to spool the compressor faster than the maximum boost level. Which is like the old school turbos.

If you put it in an application where it can overboost your engine, you'd better install a wastegate.

 

Well, continue to do your research and reading. Pitts Power has NON-WASTEGATE turbos for direct replacement on Series 60 engines as a recommended performance modification. Most of the major diesel power shops like Area Diesel in Des Moines, or Rochester Fuel Injection out of Rochester, MN also recommend the Borg Warner 171702/S400 non-wastegated turbo to really bring out the performance of the Series 60 used over the road. Read about the 171702 here also.....

https://www.rochesterfuel.com/produ....html?osCsid=10f0d597ebbc79e85dd27f2e196440bb

I personally know a couple of guys that have replaced the wastegated Garrett turbo on their Series 60's with BW 171702 turbos and would have it no other way. Several people have eliminated the problematic manifold center section cracking by freeing up the exhaust with one of these non waste gated turbos. They have a much larger T6 housing that greatly reduces restriction. Many claim to have gained mpg going to these, but there are so many snake oil claims out there from many other products that I won't say one way or the other. But it has been documented that going to one of these, EGT's drop 100-150 degrees due to better exhaust flow.

If anyone has doubts about my comments, feel free to check in with any of the major shops that specialize in Detroit Series 60 performance and get their opinion. You will probably get similar recommendations. Maybe the brand name will be different, but every shop will generally say "dump the waste gate". And all the earlier Series 60's (DDEC I, II, III) and even the very early DDEC IV's came from the factory with non wastegated turbos.

 

Well yea, all old turbos were not gated. There was no way to adjust boost pressure, nor was there a variable geometry on the compressors. That was early in turbo design.

These BWs are interesting. I could see the reduced temps. On a big engine like in trucks, it would work well due to the high boost pressures the crank could handle. It definitely wouldn't be safe on lesser applications. It might work out on a pickup truck diesel engine, just cause the engine couldn't push the sheer size of the impellers hard enough to overboost. You probably couldn't even keep a gasoline engine running period due to exhaust pressure not being able to turn them.

Edit:

I just got through reading where a guy put a BW on his dodge cummings. He said the lag was horrendous and he had no power lol. Definitely need high exhaust pressure for them, it seems.

What are the solid numbers on max boost pressure that a stock Detroit could handle on it? I'm sure it could probably take at leadyv60 psi, yea? At least I'm short bursts.

 

They sound horrible and obnoxiously loud. I did my '03 Western Star with pre-EGR DDEC4 12.7L with a 14" resonator and I hated it.

Same truck and exhaust with a 6NZ sounded great.

 

I know of several that are using the 171702 and developing upwards of 45# of boost consistently. Where the BW really comes into its own is when the stock exhaust manifold is replaced with a ported and coated manifold. The flow is substantially improved. As the for the 171702, the modern version of it is from the Airwerks division of BW. It is the S400SX4-75. Now that is the top line non wastegated turbo for the 12.7 and 14 detroit 60's. I will grant that turbo spool up is not as fast as with a wastegated version, but then, only those really involved in local P&D would notice. For OTR and working loads over terrain, the BW turbos maintain higher boost and the EGT's are greatly reduced on pulls. High exhaust flow equates to lower EGT's, more power, and better mpg. Also, the center section exhaust manifold cracking on the 12.7 that is common with the wastegated turbos is virtually eliminated. Why put a nozzle on the end of the garden hose (i.e. wastegate) when you can get maximum exhaust flow by using a non wastegate? If one is only worried about breaking out at the traffic light in town, then a wastegated turbo would be better, but if one is wanting to maximize engine performance and mpg out on the road, then the wastegate is a hinderance. As with anything, it is what you are intending to do as to what works best. And since most here are doing some form of OTR, a non wastegated turbo would be an improvement over the stock wastegated one.

Equating a Cummins in a Dodge to a 12.7 Series 60 is hardly an apple to apples comparison. I could put one on my 2.8L diesel in my Jeep Liberty, but I would probably not like the performance either. Try doing some searches over various forums that talk about the 171702 on the Series 60. You might see a different view than the one about putting it on a Dodge Cummins. As for developing boost on the Detroit, why would anyone want to develop 60 psi? 1 lb of boost equates to approximately 15-20 hp on the engine. If one is truly driving the truck and not just a steering wheel holder, they wouldn't apply more than 30# of boost on a pull anyway. Otherwise you are just burning up fuel for no good reason. With increased power and performance, comes increased responsibility to drive it right.

 

Also, just to correct a little misinformation, variable geometry has nothing to do with the compressor side of the turbo, it's all done in the exhaust.

The real gain from having a wastegate is that you can run a smaller exhaust housing to help with low end response, the A/R of an exhaust housing plays a major part in how a turbo spools. A properly speced turbo does not need a wastegate, while it may be slightly slower to build, it will flow at full power.

 

detroit w/straight pipes = invest in earplugs