VGT Feeding a Non-VGT Compound Setup.

[Tuscany]

Ok...... First things first, I do not want this to be a pissing match about which setup would be better/work etc. This is a thread that I want to ask all the guru's and what not or anyone with experience in compounds about if this would be possible.

I know that it has been tried in the past without any success, but that was also when tuning was primitive at best and the injector/turbo game was in the early stages for the 6.0L.

That said this is what I hope to accomplish with this thread. I want to try to run a compound setup using a VGT turbo to feed a Non-VGT turbo. I plan to start small for test purposes as it could get VERY costly blowing apart VGT turbo's because of excess back pressure or over speeding it. Now if it turns out that this is actually possible through tuning and or the use of one or multiple wastegates than I obviously will up the fuel system to support larger injectors and go all out with bigger turbos and injectors.

Now that is all said let's hear the ideas.

Again this is a brain storming thread for thoughts and collaborating ideas to make this work between fabrication, piping, tuning and anything else needed to make it possible. Thanks in advance guys.

[strokin6L]

This has been tried years ago by a few. Waaay to much BP using the vgt. Now that MTW has some awesome turbo's out...it might be doable with one of them, but it'd be pointless really. Cause a non vgt turbo would be way cheaper as the high pressure rather than the vgt.

[kdogg85]

I can't remember exactly why it wouldn't work for the 6.0's, but I think it was more to do with the speed at which the vgt solenoid would act and the response time and limits in the pcm. If you could somehow rig up the vgt solenoid off the 6.4(I think it is a very fast acting solenoid) and get a pcm to work with all the other stuff with the 6.0 engine controls(mainly injection) then there should be no reason it shouldn't work.

Are you wanting to put an Mtw stage 4 over an s598 or a big gtx series charger?

[Tuscany]

Originally Posted by kdogg85

I can't remember exactly why it wouldn't work for the 6.0's, but I think it was more to do with the speed at which the vgt solenoid would act and the response time and limits in the pcm. If you could somehow rig up the vgt solenoid off the 6.4(I think it is a very fast acting solenoid) and get a pcm to work with all the other stuff with the 6.0 engine controls(mainly injection) then there should be no reason it shouldn't work.

Are you wanting to put an Mtw stage 4 over an s598 or a big gtx series charger?

I think that between wastegating and tuning of the VGT solenoid it should be possible to do. Eventually if it was in deed possible to do this type of setup I was thinking of maybe a MTW stage 3 feeding a Garrett GTX4708R or the 5 series GTX turbo. Again that is wishful thinking down the road. At this point I want to see if it is possible with a smaller setup with say a stock VGT feeding a S366 or the MTW stage 1 I have feeding a S366. Something that is relatively inexpensive for R&D incase I blow some turbos apart in the future.

[strokin6L]

Like i said earlier...it's been done and works. Has nothing to do with the solenoid. The problem was the turbine side of the VGT...it's waay too small. It had soo much back pressure using the vgt and the gaskets wouldn't last long.

[Tuscany]

Originally Posted by strokin6L

Like i said earlier...it's been done and works. Has nothing to do with the solenoid. The problem was the turbine side of the VGT...it's waay too small. It had soo much back pressure using the vgt and the gaskets wouldn't last long.

Yes it has been tried in the past but it was unsuccessful because of the back pressure and no one knew how to really tune the VGT. That was back when the 6.0 performance world was relatively new and the tuning was primitive at best. Yes the VGT on a stock charger is going to be WAY to small to run say a S475 or what not but trying it out on a small scale first with a stock turbo feeding a 366 or something like that would be doable. Also I am talking about using wastegates in conjunction to VGT tuning to keep bp down in the safe levels to not blow apart any turbos.

[strokin6L]

tuners knew how to tune the VGT turbo back in the day...tuning wasn't the issue....the turbo itself was.

[Tuscany]

Tuning wasn't what it is now by any means. Again I don't want this to be a pissing match I want this thread to be ideas on how this could work or what would make it work.

[strokin6L]

really? What all has changed other than FICM tuning? Not a whole lot has changed in tuning.

[Six0~Stroker]

I agree with this guy!^^^



Sure stuff has been modified/tweaked for Adrian's turbos.... But not Changed!
There has not been any "AHA" moments with our current popular tuners that everyone knows about... I'm pretty sure that back in the day when this has been tried... say Eric or Matt probably most likely tried a bunch of different combinations of tunes but it just wouldn't work....

But, lets try it again