Gateing stock VGT

[McRat]

The factory VNT is not "split snail", so just using an LBZ (larger) pass side riser should be sufficient sized to deal with both sides, IMO. Just make a wastegate adapter to put the gate where the EGR log goes, and put the vent pipe out the wheelwell.

What people have found though, is blocking off a gate tends to make more HP on a diesel. You put a gate in for durability, but if you're looking for power, not sure it will help.

If you open the vanes to the optimum flow, about 15% IIRC, you only make 22 psig boost. So releasing more of the hot gases might lower the peak boost you can achieve.

But this is based on stuff I dinked with 5 years ago, so my facts might not be reliable.

 

[Redbowties88]

The factory VNT is not "split snail", so just using an LBZ (larger) pass side riser should be sufficient sized to deal with both sides, IMO. Just make a wastegate adapter to put the gate where the EGR log goes, and put the vent pipe out the wheelwell.

What people have found though, is blocking off a gate tends to make more HP on a diesel. You put a gate in for durability, but if you're looking for power, not sure it will help.

If you open the vanes to the optimum flow, about 15% IIRC, you only make 22 psig boost. So releasing more of the hot gases might lower the peak boost you can achieve.

But this is based on stuff I dinked with 5 years ago, so my facts might not be reliable.

anyones facts are better then no facts:thumb:

its entirely possible that this could do nothing at all or make it worse..who knows at this point...but im thinking that having the vanes at a higher level while there is less exhaust flowing through the turbine may increase the efficiency...but of course thats only a guess/theory

 

[duratothemax]

The factory VNT is not "split snail", so just using an LBZ (larger) pass side riser should be sufficient sized to deal with both sides, IMO. .

ok pat so the factory turbo isnt really "twin scroll" or anything? So if you only gated one up-pipe it wouldnt make it like the pass side is running 10x cooler than the driver side???

 

[sweetdiesel]

ok pat so the factory turbo isnt really "twin scroll" or anything? So if you only gated one up-pipe it wouldnt make it like the pass side is running 10x cooler than the driver side???

If that was the case wouldn't it be the same as the Egr opening on a stock setup?

Doesn't seem to be a issue there right?

 

[Redbowties88]

If that was the case wouldn't it be the same as the Egr opening on a stock setup?

Doesn't seem to be a issue there right?

yea but egr normally wouldnt open under heavy boost or throttle....

 

[McRat]

ok pat so the factory turbo isnt really "twin scroll" or anything? So if you only gated one up-pipe it wouldnt make it like the pass side is running 10x cooler than the driver side???

I don't think so, but I suppose it could. The driver's side gases would have to do a gentle 180 to get to the gate and travel a foot further, but they would be vented. Nothing in our stock exhausts is smooth or high flow.

 

[LBZ]

yea but egr normally wouldnt open under heavy boost or throttle....

Yeah it can open. That's why the need for the blocker plate. Even with the egr turned off it can be forced open at higher pressures.

 

[Fingers]

The LLY vanes are a good bit thicker to fill the throat of the scroll, but their profile is the same across all the versions that I have looked at. The LLY flows the most.

The aftermarket VVT has vanes with a better profile that generates boost with less back pressure. But ultimately, the turbine change is where the big advantage is. You can only get so much out of the stock spool.

 

[duratothemax]

is anyone doing an aftermarket higher flowing turbine wheel for the VVT's?

 

[Redbowties88]

x2 on that....but at this point your almost at the might as well buy a new turbo point...

clipping the turbine wheel helps also im sure....if only a little bit

 

[hondarider552]

Also a possibility of melting/breaking the turbine wheel too..

 

[ripmf666]

At one point later down the road I plan to replace the stock LBZ vvt with the 4094avnt and maybe stepup the Gt45 in the Mpi kit. And add Ricks manifolds when I can first. Since I run twins inhave lots of room behind the stock turbo. I was going to have Ricks add Y tithe up pipe the. Mount the waistegate there and dump it down into my exhaust. And also still run the waistgate that the Mpi kit has on it going tothe Gt45. I think this would cut back on drive pressure but not sure were I'm at now since I don't run a DP yet.

 

[Redbowties88]

Also a possibility of melting/breaking the turbine wheel too..

Yea that's what I was thinking too. But according to Freddy you'll crack the housing from heat before you melt the turbine. Whether that's actually true or not I have no idea.... Did you get you ported manifolds back from him yet?

 

[duratothemax]

Yea that's what I was thinking too. But according to Freddy you'll crack the housing from heat before you melt the turbine. Whether that's actually true or not I have no idea.... Did you get you ported manifolds back from him yet?

that is most certainly not true.

 

[Redbowties88]

OUCH.... well there goes that idea right out of my head.

was that a bone stock turbine ben?

 

[duratothemax]

OUCH.... well there goes that idea right out of my head.

was that a bone stock turbine ben?

yes, factory stock LLY turbo.

 

[JoshH]

Did something go through it?

 

[Redbowties88]

on another note..DAMN those vanes are wide.....

 

[Redbowties88]

i dont think it would be that even if something went through it more like heat damage...but i could be wrong

 

[Mike_S]

Yeah, I'd say heat...Thats what my LB7 turbine looked like after a WOT run of about 3/4 mile and the EGT gauge pegged at 1600 degrees for most of that run...oops.