Lets talk vnt's for a bit.

[Zaro]

I have had the idea of running a vnt 17/22 on my aaz lately

I currently have a complete rebuilt engine, with a new head with 3 angle valve job, some sort of custom really aggressive cam. Front mount intercooler behind the grill with 2.5 inch piping. A custom intake manifold with a 3 inch inlet. A giles pump built to fuel 200 whp and 35 psi... And a fuel cooler. I had a t3 50 trim that i was planning on running but I had to sell. At the moment Im just running a NEW VW garrett t3 I got from the local dealer a while back as a temp turbo.

What kind of power is 17/22 capable of? I dont really care about fast spool to much but id like to stay under 5000 rpm. Ive had an aaz in the past that reved to 7000 or more and made 50 psi out of a t3/t4.

Im really just in the thinking stages. The engine is in my mk2 gti and I put about 8000km on it since the rebuild in feburary.

Controlling it is NOT an issue. My father is running a 17/22 in a syncro vanagon on his aaz with a Dawes device.

Looking for reliability, and the most power. Fuel economy isnt something that im to concerned about at the moment.

[RabbitJockey]

from what tdi people say they are capable of a bit over 200whp on a tdi.  so it is possible that its capable of that much on an aaz.  maybe a little less tho since tdi is more efficient.  won't know till you try running it tho.  are the guy who had the mk1 scirocco with aaz and t3/t4?

[sprstu]

the issue youre going to run into is controlling the VNT actuator. The VNT's are great turbos if you can control them properly, its not as easy as a bleeder wastegate. The VNT is a "smart" mechanism that is wildly powerful and efficient when controlled properly. Many people have built systems to run them off the throttle postion lever on the pump but youre really not giving yourself the full advantage of the VNT. There is more to it than just "vanes open" "vanes closed"

if you were making good power with the T3/T4 why did you switch away from it?

[wolf_walker]

I gave up talking about VNT's till there is a plug in laptop tunable ala megasquirt control solution that I can buy for a couple hundred bucks.

[Gizmoman]

OK,
I ran across these links doing a search here. . .
http://dmn.kuulalaakeri.org/vnt-lda/ You'd have to have some programming skilss though.

An apparently successful manual controller "was" here. . .
http://www.vwdieselparts.com/forum/viewtopic.php?f=21&t=11042#p76175

At that time he was libbybapa, he now goes by libbydiesel and is a current member here

[wolf_walker]

Yep, seen em. Awesome and much respect, but not what I'm wanting.
I wouldn't be so picky if I'd never used megasquirt.

Sent from my SCH-I535 using Tapatalk 2

[fatmobile]

I gave up talking about VNT's till there is a plug in laptop tunable ala megasquirt control solution that I can buy for a couple hundred bucks.

 The thread title is let's talk about VNTs.
 Not let's think of reasons not to talk about VNTs.

[Zaro]

the issue youre going to run into is controlling the VNT actuator. The VNT's are great turbos if you can control them properly, its not as easy as a bleeder wastegate. The VNT is a "smart" mechanism that is wildly powerful and efficient when controlled properly. Many people have built systems to run them off the throttle postion lever on the pump but youre really not giving yourself the full advantage of the VNT. There is more to it than just "vanes open" "vanes closed"

if you were making good power with the T3/T4 why did you switch away from it?

The t3/t4 was on a different engine which had h-beam rods, machined pistons for lower compression, crank girdle, extremely ported head and custom manely valves.

This new engine is just a stock rebuild with only head studs and 3 notch head gasket. I dont want to rev a stock bottom end to 6500 and run close to 50 pounds of boost. But then again maybe thats what I should be running so boost would come on slower and more in the top end...

I assume a VNT 17/22 would hit hard very low rpm which would make a few extra "windows". lol

Im more or less looking for turbo ideas to reach, give or take a few numbers, 180 hp out my aaz. I do have sitting right beside me an aba turbo exhaust manifold and a near new t3/t4 with a .50 ar. Yes I agree a .48 ar would be better yet but I already have this.

Thoughts???

[RabbitJockey]

the issue youre going to run into is controlling the VNT actuator. The VNT's are great turbos if you can control them properly, its not as easy as a bleeder wastegate. The VNT is a "smart" mechanism that is wildly powerful and efficient when controlled properly. Many people have built systems to run them off the throttle postion lever on the pump but youre really not giving yourself the full advantage of the VNT. There is more to it than just "vanes open" "vanes closed"

if you were making good power with the T3/T4 why did you switch away from it?

The t3/t4 was on a different engine which had h-beam rods, machined pistons for lower compression, crank girdle, extremely ported head and custom manely valves.

This new engine is just a stock rebuild with only head studs and 3 notch head gasket. I dont want to rev a stock bottom end to 6500 and run close to 50 pounds of boost. But then again maybe thats what I should be running so boost would come on slower and more in the top end...

I assume a VNT 17/22 would hit hard very low rpm which would make a few extra "windows". lol

Im more or less looking for turbo ideas to reach, give or take a few numbers, 180 hp out my aaz. I do have sitting right beside me an aba turbo exhaust manifold and a near new t3/t4 with a .50 ar. Yes I agree a .48 ar would be better yet but I already have this.

Thoughts???

what?  t3 t4 is too big for that power, im not saying it won't work but it won't work as well as a proper sized turbo.  what are you talking about with the size?  50 ar what???  there is no 50 a/r in t3 t4 stuff except for a somewhat uncommon t3 compressor housing.  do u mean its a 50 trim t4 compressor?  and .48 would be the turbine housing (hot side) a/r size

[Alcaid]

Holset HE211W and Garrett GT2056 are both good 180+ IDI bhp turbos

[8v-of-fury]

I gave up talking about VNT's till there is a plug in laptop tunable ala megasquirt control solution that I can buy for a couple hundred bucks.

 The thread title is let's talk about VNTs.
 Not let's think of reasons not to talk about VNTs.

How is your post or this post I am writing now any different haha.

I too would like to see some good solid info on VNT's, something I may think of in the future.

[Gizmoman]

Me as well.