Based on the response I felt from the 6.7L I drove, I'm thinking this might be a fantastic way to go for a DD truck.

I'd like to know more about how the VGT is controlled. Being able to use it as an E-brake would be sweet, too...

Anyone?

 

Hohn, I noticed they are dang cheap on Ebay as well. I was just worried about trying to rig up some sort of a boost activated controller for the VGT part.

I think I could dang near bolt one of them up on my rig. Don't know how to control it though. In another month I finally end my college career and start my professional career. Maybe in a couple more months I'll have the cash to play with one of these turbos. You know, buy one off ebay and throw 12 volts at it to figure out what does what.

 

I've been pondering this as well. I think the coolest thing would be using the exhaust brake. They're almost cheap enough to buy one and play around with the controls and see how it operates... If I had a couple hundred extra dollars laying around...

 

Crimedog, if you rigged up a 3rd gen turbo like me, you can use a cast elbow with the exhaust brake. JLent uses an aftermarket 3rd gen turbo on his second gen and used the cast elbow off a newer third gen with the exhaust brake.

So far, my setup has been reliable and it cost me about 500 including the turbo. I have experienced and increase in HP and a little better egt control.

The VGT would be wicked for sure, I just wonder how reliable the VGT system is. My truck makes a lot of soot if you know what I mean! Not so good for moving parts in the exhaust system.

 

The guy who develops a kit to adapt the VGT to older trucks will make some money..

 

Holset's VGT scheme is the most reliable of the different types in use, but the 6.7L model has had some issues with extended idling & light load operation.

However, I think the real challenge is controlling the nozzle actuator properly - and I don't see how that's possible with the limited amount of code the 24V ECM is designed to handle.

 

I don't think the 24V ECM could be made to control the VGT-- a standalone solution would have to work.

 

Exactly - and that's a huge amount of data that has to be processed in real time, sampling at over a 100X/sec.

You'd need something like a TurboSmarty... still, it's awfully tempting to engineer a low-buck solution with cruder resolution. Like using a modified sine wave inverter instead of a fancy electronic true RMS-type.

I bet $50 at Radio Shack would get the small parts to make up the control & load circuits to operate the VGT, and using the ECM's injector duty cycle signal circuit would be a good place to start.

Hmm - the more I think about this, the more I want to do it!

 

Do it XLR8r!!!!!!!!!!!!

 

Oh, QUAAAAAAAA AAAAAHHD!! Where AAAARREE YOOOOUUUUU?

 

What exactly is the VGT?

And how is this supposed to work on our 24v's?

SOrry for the dumb question, but I doubt I'm the only one who doesn't know what it is.


Thanks for the clarification!

 

 

The Cummins Variable Geometry Turbo operates differently than the sliding vane configuration pictured above.

See flash animation here:

http://www.holset.co.uk/files/2_5_1_5-VGT.php

They both work pretty well-- Cummins went with their approach because of the simplicity of it improving reliability. (all those moving vanes are potential failure modes).

jh

 

I know it wouldent be optimal but why couldent you have a system where you had multiple nodes or settings for different driving situations. instead of having the turbo continuously varying??

 

You could do that-- set it up so it has just simply three points-- fully closed, fully open, and halfway between.

jh