VNT into a 603...contemplating it - PeachParts Mercedes-Benz Forum

awsrock · #1 05-13-2009, 02:31 PM

Hey guys

So I've been toying with the idea of swapping a VNT onto my 603. I know the Finns have done all sorts of wizardry, but I have yet to hear about anyone doing it on this forum.

I still have a lot of research to do, but any thoughts from those of you who have done this with your 617s (Forced, Bgkast?)

From what I've read, it seems like I'd want a GT2256V minimum. I've been playing around with some equations (which I may have done wrong) and it seems like I would be best off with something in the GT22-25 series.

I'm mostly interested in efficiency and quicker spooling, although at most I might turn up the IP to full load. I don't need anything crazy on there

Not looking to go more than 15psi max. A flatter torque curve would be nice.

Are there any major drawbacks to the 603 set-up that are keeping people from trying this out? Emissions junk in the way? All the Garretts I've been seeing on their website are t25 flange, but there are adapters for a t3 to t25. Some of the pics of Finnish superturbos you all have posted looked like they didn't have to move too much around, other than the air filter situation. Would custom headers be required?

Anyway, if this would even work, I probably wouldn't do it for another 6 months, so I have plenty of time to think it out. Ideally, I'd like to keep the cost under $1000, which I think is very attainable.

winmutt · #2 05-13-2009, 03:39 PM

Unfortunately between the 22 frame and the 37 frame there are not many options. I think the opel gt35 is probably tits but hard to find. Holset might be your best bet but again, the turbos that would flow the best for our cars seem to be hard to find.

#3 05-13-2009, 10:18 PM

A 2256 would be bare min. for a turned up 603. You would be best to look for a GT2559V or GT2560V from a BMW. There is a GT3063KLV used on Hino trucks that would work very nicely. The Holset HE341Ve, which I'll be using on my 300D, is about a GT35 but its a rare find.

awsrock · #4 05-14-2009, 08:32 AM

Thanks for the info, guys. I'll keep an eye open for some of those models.

Forced, do you know off hand what BMW models had those two turbos?

My girlfriend's dad is the parts department manager for a Dodge dealerships, so I might ask him to keep an eye out for any used Sprinter turbos too.

awsrock · #5 05-14-2009, 08:41 AM

http://cgi.ebay.com/ebaymotors/Garrett-T25-VNT-Diesel-Turbo-GT-GT25-T3-IHI-KKK_W0QQitemZ160335109096QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item2554b79be8&_trksid=p4506.c0.m245&_trkparms=72%3A1171%7C65%3A12%7C39%3A1%7C240%3A1318

How about this guy? First good looking deal that I've come across. Looks like it might be electronically controlled? Can you change that over to mechanical, or should I keep looking? It sounds like it might be kind of small if it's only a 45 turbine wheel. I can't seem to find what GT model it is based on "M24N" edit: Upon looking through turbos on your STD website, it looks like this is a 2559v! So now the question is, can I swap the electronic wastegate to a vac operated one? If so, I've found my turbo!

I also found a Sprinter website that has used turbos for like $275. Not the best deal, but not bad if I can't find anything else.

AND, I found an HE341 on ebay...good price. I feel like that might be too big, though?

winmutt · #6 05-14-2009, 09:59 AM

40/45 that sounds way small.

Quote:

Originally Posted by awsrock

http://cgi.ebay.com/ebaymotors/Garrett-T25-VNT-Diesel-Turbo-GT-GT25-T3-IHI-KKK_W0QQitemZ160335109096QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item2554b79be8&_trksid=p4506.c0.m245&_trkparms=72%3A1171%7C65%3A12%7C39%3A1%7C240%3A1318

How about this guy? First good looking deal that I've come across. Looks like it might be electronically controlled? Can you change that over to mechanical, or should I keep looking? It sounds like it might be kind of small if it's only a 45 turbine wheel. I can't seem to find what GT model it is based on "M24N" edit: Upon looking through turbos on your STD website, it looks like this is a 2559v! So now the question is, can I swap the electronic wastegate to a vac operated one? If so, I've found my turbo!

I also found a Sprinter website that has used turbos for like $275. Not the best deal, but not bad if I can't find anything else.

AND, I found an HE341 on ebay...good price. I feel like that might be too big, though?

#7 05-14-2009, 06:33 PM

Quote:

Originally Posted by awsrock

http://cgi.ebay.com/ebaymotors/Garrett-T25-VNT-Diesel-Turbo-GT-GT25-T3-IHI-KKK_W0QQitemZ160335109096QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item2554b79be8&_trksid=p4506.c0.m245&_trkparms=72%3A1171%7C65%3A12%7C39%3A1%7C240%3A1318

Beware of that one. It looks like somebody tried to clip the turbine wheel.
If thats the case then the turbo is scrap metal. They claim it "improves flow" but it really turns it from a turbine into a paddlewheel.

Clipped-not clipped.

bgkast · #8 05-15-2009, 02:55 AM

Quote:

Originally Posted by ForcedInduction

Beware of that one. It looks like somebody tried to clip the turbine wheel.
If thats the case then the turbo is scrap metal. They claim it "improves flow" but it really turns it from a turbine into a paddlewheel.

It's hard to tell, the pictures are way too small. Never buy an ebay turbo unless you can get good pictuers of the compressor and turbine wheels.

#9 05-15-2009, 04:33 AM

The seller replied to my question:

Quote:

Dear diesel-benz,

Yes, it is clipped, not sure what degree, but not heavily.

- gmedlicott

The turbo is scrap metal, its definitely not worth the $100 first bid unless you're sure the compressor wheel can be fitted to a Sprinter turbo.

awsrock · #10 05-15-2009, 09:11 AM

Darn. I'll keep looking.

Why do people clip the wheels?

Would an HE341 be too big / would it fit? It sounds like it is a big setup.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=320371284448

Thanks for the heads up, Forced. I'm learning as we go.

DeliveryValve · #11 05-17-2009, 01:49 AM

Quote:

Originally Posted by ForcedInduction

The seller replied to my question:

Quote:

Dear diesel-benz,

Yes, it is clipped, not sure what degree, but not heavily.

- gmedlicott

The turbo is scrap metal, its definitely not worth the $100 first bid unless you're sure the compressor wheel can be fitted to a Sprinter turbo.

I got some better pics from the seller. Is it clipped or not...

If indeed clipped, too bad it is still too much for me to try the compressor wheel and housing on my damaged GT2256v.

My damaged GT2256V.

.

#12 05-17-2009, 02:05 AM

Yep, clipped for sure.

panZZer · #13 05-20-2009, 04:28 PM

Beware

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=160335109096&_trksid=p2759.l1259

michakaveli · #14 06-02-2009, 05:53 PM

Can someone elaborate on the this "clipping" technique that has been portrayed. Looks like this clipping reduces the actual surface area of the blade that bring air into the turbo.... yes?

DeliveryValve · #15 06-03-2009, 01:39 PM

Quote:

Originally Posted by michakaveli

Can someone elaborate on the this "clipping" technique that has been portrayed. Looks like this clipping reduces the actual surface area of the blade that bring air into the turbo.... yes?

Per the Garrett website.

Quote:

Clipped Turbine Wheel
When an angle is machined on the turbine wheel exducer (outlet side), the wheel is said to be "clipped". Clipping causes a minor increase in the wheel's flow capability; however, it dramatically lowers the turbo efficiency. This reduction in efficiency causes the turbo to come up on boost at a later engine speed (ex. increased turbo lag). High performance applications should never use a clipped turbine wheel. All Garrett GT turbos use modern unclipped turbine wheels.

In other words, the exhaust is flows with less restriction. Mainly for top end power with loss of low end power because of a later spool.

.