Variable Geometry Turbo for the IDI.

[88 Ford]

Im sitting here in my work truck 2011 f550 6.7 psd thinking ... wonder if they would notice a missing turbo .... then I thought what about twin vgts... now that's a nasty thought

I actually got corrected earlier. The 6.7 actually has a duel compressor bot compounds like the 6.4. Its a neat setup though. Look it up.

 

[jwalterus]

I know Garrett sells boost actuated VGTs......

yup, it was developed and stock on the 04-05 D-max engines, which also happened to be 17.5:1 compression, boost was in the 18-23 PSI range from the turbo, and it was set up to use it as an exhaust brake as well (I remember watching it on either Stacy David's Gears or Hot Rod TV when they were coming out)

it seems like you could feasibly pull the controller and turbo off a rolled 04-05 silverado and get it to work on one of our trucks, too bad if you need a replacement a reman turbo is around 1800 and 450 core charge

 

[429idi]

What are the dimensions on both of your turbos?

the t70 compressor would be 70mm inducer by 90mm exducer. And the tbird turbo would be a t3 not sure what size. It would be way too small for one of our engines though. Even as a high pressure turbo. I think they will flow 350cfm.

 

[88 Ford]

the t70 compressor would be 70mm inducer by 90mm exducer. And the tbird turbo would be a t3 not sure what size. It would be way too small for one of our engines though. Even as a high pressure turbo. I think they will flow 350cfm.

That's kind of what I was thinkin. It definitely depends on the cfm level. I was kind of thinkin a properly size small turbo and a variable turbo would be a cool setup on our trucks. The smaller turbo would spool quickly and variable turbo would spool almost as quickly too. It would kind of be like a setup on a 6.4 PSD.

 

[88 Ford]

So I have been doing some research and a lot of the setups that only use either boost or drive pressure to open the turbo have problems with the turbo barking. This is even a problem when using spring pressure to slowly open the vanes on the turbo also. So one way to prevent this would be either to add a blowoff valve or to use a duel actuator type setup. I think if you use both drive pressure and boost, it will prevent the vanes from slamming closed quickly like they would otherwise if there was only one way to actuate the turbo. I think this might be a good type of actuator to use, but correct me if I'm wrong.

http://www.ebay.com/itm/AIR-CYLINDE...ic_Hydraulic_Valves_Parts&hash=item231131e9b0

But anyway, using both dp and boost to actuate the vanes would keep balance in the system and would work out well I would think. If I were to a setup like this, I would use the dp to open the vanes and boost to close the vanes. But one problem with this would be that the boost might not allow the vanes to open all the way, so I would use a manual boost type controller to bleed off some of the boost thus allowing the dp to open up the vanes all the way. This setup would surely take some tuning like any setup like this but does have potential for some good power. Anyway, what do you all think? Its not an original idea cus the guy from the CompD thread used it but overall I believe it is the best way to set it up and it has even allowed him to go with a compound setup with the Vgt.

 

[FordGuy100]

Both boost and backpressure would open the veins up I believe? Backpressure would open it so that the turbo doesn't speed, and boost to open them so that it's harder to overboost.

 

[88 Ford]

Both boost and backpressure would open the veins up I believe? Backpressure would open it so that the turbo doesn't speed, and boost to open them so that it's harder to overboost.

I was thinking that they would counter each other unless the is not the right type of actuator. I was trying to find the type where they would counter against each other and balance the turbo.

 

[94IDIT]

I was thinking that they would counter each other unless the is not the right type of actuator. I was trying to find the type where they would counter against each other and balance the turbo.

I'm no expert but I'm not sure if a perfect balance could ever really be achieved without computer controll A dual actuated setup with a BOV sounds like it'd be the way to go... Or even just a single acutated setup with a BOV.. IMHO a BOV would just be a good safeguard to have, kinda like an external gate... Just my thoughts though.

 

[Hyde]

I was thinking that they would counter each other unless the is not the right type of actuator. I was trying to find the type where they would counter against each other and balance the turbo.

If equal pressure were going to both ports it would still extend. The area of the piston on the extend side is larger than the retract side due the the rod taking up the extra space on the piston.

 

[88 Ford]

If equal pressure were going to both ports it would still extend. The area of the piston on the extend side is larger than the retract side due the the rod taking up the extra space on the piston.

From the setups like this that I have seen, there is only one point where the drive pressure and boost are equal and then after that boost is higher cus the vanes are all the way open and dp is reduced. Also, with a Vgt you still do want it to extend, so that is a good thing. And even if it doesn't extend enough, you can tune it by bleeding off some of the boost pressure so the vanes do open up all the way. Idk I was just thinking of a way to prevent turbo bark by keeping the vanes from closing so quickly...

 

[Hyde]

Blow off valve.

 

[88 Ford]

I'm no expert but I'm not sure if a perfect balance could ever really be achieved without computer controll A dual actuated setup with a BOV sounds like it'd be the way to go... Or even just a single acutated setup with a BOV.. IMHO a BOV would just be a good safeguard to have, kinda like an external gate... Just my thoughts though.

There is an equalization of pressure in the systems that I have seen but it is only for a short amount of time. And a BOV is always a good safeguard. I have one for my supercharger setup for when I have that done.

 

[88 Ford]

Blow off valve.

I know. I was getting to that. Haha.

 

[88 Ford]

Oh also another thing I thought about is that the turbo will bark until the BOV releases pressure. So anything you do with the setup as extra precaution is a good thing.

 

[Black dawg]

are you guys talking bov, like to let go boost pressure?

wont that make an oily mess eventually?