So are you having flow issues with the 363/68/.83?

 

No issues out of the 636/68/.83, I was just generally speaking about VGT/VNT turbos. The variable geometry housing allows a smaller turbine wheel to have the benefits of a larger one at upper RPM. Whereas a larger turbine can spool faster at lower RPMs.

Take a 2 VGT housings, for example a 63/74mm and a 63/68mm. The VGT has a listed range of .50ar-1.1ar.

So a moderate motor say 300-350hp running a 363/74. What is the benefit of the equivalent of a 1.1ar housing in the upper RPMs? I dont really see the need to open up the turbine flow THAT much on the top end to keep EGT/pressures in check. On the lower RPM with a 63/74 VGT you are just trying to get it (for discussion sake) to spool like a 63/68. Sure seems like a trade off between using the entire spectrum of the VGT vs. just using it to spool a larger turbine faster. (at a moderate HP level)

Take the same motor but now a 363/68. It is more likely to use the full range of the VGT. It becomes more realistic to use the full 1.1ar of the housing because naturally the 68mm will produce more pressure. Now instead of trying to spool a bigger turbo faster, you are spooling a smaller turbo faster but not limiting the top end flow.

 

I don’t understand the desire to add complexity to a turbo that’s already working well. I agree it would open up the restriction on the upper end flow. But if there are no issues then why bother? I have watched the EBP ratios along with other data and don’t feel my current setup with stock injectors and the .91 housing is restricting performance in the upper rpm/load ranges. It seems to be flowing fine as is. I could always go for a little more bottom end though, which is where your .83 comes in. If I ever see enough data on EBP ratios with that housing then I may make 1 last turbo change.

Now, throw in large injectors with frequent full throttle runs and I can see where the VGT comes into play.

I do think it’s worth noting that FTN went up in turbo size to correct the broken shaft, along with adding the blow off valve. So which aspect fixed the issue? How would the smaller turbo react with the VGT? Would it be less likely to break shafts since it’s lighter? ——Questions I’ll never learn the answers to first hand.

 

There are people that do this?!

 

Complexity doesnt bother me much. What bothers me is when there are parts on the market that only a few people have tried and it becomes a mystery how they perform in different applications.

Personally I think if will be fine in a lower power application (300-350hp).

Email I got today.

 

Picking their brain now, the website has a Mechanical version and a 3-Stage Mechanical version. @FordTruckNoob Do you happen to know the difference? If purchased I am leaning pretty heavy toward the mechanical version.

 

I have no clue. That 3-stage mechanical is new to me too. I’ll ask my contacts there to see what is up with that.

 

I emailed him as well. Just a guess but maybe it varies the ratio between back pressure and vane %.

Ultimately the goal is to make it spool like a 2015+ 6.7 without throwing a bunch of fuel at it on the bottom end.

 

Reply from DPS.

 

Found a FB video on the 3-stage.
“https://m.facebook.com/dieselpowersource/videos/the-all-new-3-stage-mechanical-actuator-is-now-available-with-all-vgt-turbonator/2575580185908910/?locale=ms_MY&_rdr”
Wow that really cleared things up. 😑

 

@brokestroke , please PM your email address to me.

 

I have not towed more than 2k with it yet so I cannot speak to that. I have not heard any complaints yet either.

 

@mecdac loves his 6.7L with a 10R140 transmission, as do many, many others. I too have read a lot good things about the 10 speed and this is the one I would select if/when I win the lottery.

EDIT: Gotta love that reverse gearing in the 10R140 too when backing up a heavy load.

 

I never found myself wanting more gears with the 6.7/6r140, especially tuned https://rumble.com/v1bfdpf-2017-6.7-tuned-ford.html

Recently towed about 7k with the 2019 5.0 10 speed. It did really well and is a good fit for a NA gas engine, Unloaded the 10 speed is annoying compared to the 5.0/6 speed https://rumble.com/v1bffkd-2017-f150-5.0-6-speed.html

 

The 68mm Turbonator only comes in a T3 housing, they just updated their website today.