Garrett GT2052V Variable geometry turbo

[fuel]

Hey guys, I have the option of getting a Garrett GT2052V variable geometry turbo for a rediculously cheap price - it was pulled from a VAG 2.5 V6 turbo diesel engine and has done less than 1000kms. Pic here:

Now I don't know a great deal about VG turbos but have a general idea on how they work, but for all you turbo buffs I would like some advice before committing to buying it.

For starters is the GT2052V an ideal size for a 4G63 SOHC engine? It will be the DASH engine bored out to 2.1L (using 86.5mm pistons), I am wishing to run it on moderate boost levels of about 15psi, and I would be hoping to achieve 175-200kW ATW (will be multipoint inj with megasquirt, modified VR-4 cooler with 2.5" piping, 3" exhaust etc)

Secondly is the GT2052V even suitable for petrol engines? Given that it's on a diesel they typically run with lower EGT's, so am unsure how the GT2052V will cope with the higher EGTs of a petrol engine. There are a few factory petrol cars out there which run VGT's but not the GT2052V specifically (well, as far as I know).

Lastly, how would I go about controlling the vanes? The GT2052V doesn't appear to have a built in waste gate but it does have an actuator which controls the vanes, which from a general glance looks like your typical vacuum/boost activated wastegate actuator - is it simply a case of hooking the vane actuator up to a boost/vacuum source and away it goes, or is there typically a more complex controller involved? With the diesel I'm guessing the turbine is adequately designed so it full boosts a certain amount when governed by the vanes, but with the petrol am I likely to go beyond this boundary?

I was otherwise going to use the Evo3 16G but I like the idea of a VGT being able to spool much earlier and provide boost all the way through the rev range. I'm not after all out power but more so very drivable power with a good dollop of mid range torque and some power right until the 7000rpm redline.

I hope this all makes sense! Any comments appreciated!

Thanks

 

[Whoodoo]

It looks like you would need an external wastegate, and I would do some experiments to see at what pressure that actuator actuates.

The cool thing about variable geometry turbos like this as opposed to the holset style variable geometry is that you can adjust the angle at which the exhaust enters the turbine. The holset style gives you two geometries whereas the garrett kind gives any angle you want between the two extremes.

It would be cool to use a solenoid to alter the amount of boost seen by the actuator. That way, you could have the vanes change angle as the boost rises or falls.

 

[BrandonEchols]

I remember reading that there were a lot of people who preferred the Holset VGT design because of less moving parts, and therefore less chance of something going wrong. Specifically I read about the vanes getting essentially stuck from being dirty and gummed up.
Also, maybe I'm mis-understanding this...but I think the Holset and Garret achieve the same thing. The Holset design let's it spool like a much smaller AR, while maybe not varying the angle at which exhaust enters the turbine, it varies the available area of the exhaust turbine itself.
Am I off track here, or are there multiple ways to skin a cat?

 

[mpt72]

It would be interesting to see. In trucking, it seems like the vg turbos don't have the life that the regular ones do. My has the stock turbo (hx55) and its got 1.17 million on it. No problems. The vg's seem that they go after 750,000 miles. I'm not sure how that translates to the smaller ones, but food for thought, that's all. Still, seems like a cool idea.

 

[curtis]

sent you a PM.

 

[vrfour_nz]

This turbo will only flow 225 horsepower. Turbine is similar to a TD04 size & compressor is 36mm inducer and 52mm exducer. It is common for the vanes to carbon up and seize on these,the shafts also have a tendancy to bend in multiple places when boost is turned up on the steps close to the compressor wheel and seal plate and between the main bearings.