turbo advice for my build!

[alex17young]

Hi folks, parts are slowly trickling in for my 1.6td build that I will be swapping into my '81 rabbit. The donor came from a '91 jetta, ebay buy lol, took the head off and found 8 visible cracks. So I decided on a full rebuild, new head, .20" over pistons, but it hasn't been to the machine shop quite yet. I've spun wrenches for a couple years and have done plenty of work to my 1.6na but this is my first full rebuild. My goals is to have a fun, efficient, sleeper to commute to work in. I plan to intercool it, use the stock pump (for now), studs, aaz head gasket, and turbo lag doesn't bother me as long as it does light eventually. Anyways... I have 3 turbo's sitting in my garage, all of which need rebuilt. I have the stocker Garrett T3 (what's the nickname for this one???), another Garrett with the real T3 flange from a Saab 900 i think (tbo123), and I have a gt1749v (vnt15) that I bought the other day becasue I read some threads on here and had good reviews. The first two non vgt's are very close in size, I think the saab may have a slightly larger compressor wheel. The vnt15 seems so small, is it capable of 20+psi? It doesn't spin freely and the vanes are somewhat stuck i think. Is there an easy way to make the vnt a hybrid? What turbo is the best for my project? -thanks

[theman53]

There is a thread in the FAQ section for a rebuilder that I highly recommend.

I know nothing of the saab turbo, but if Trevor gets on here he would probably be able to say if that maybe a good one.

I loved my KKK K24 which is similar to the T3, so that gets my vote. . . Only because a vane control system isn't an off the shelf item for the VNT. If it were from what I have read the VNT 15 is a great turbo on these cars. I hate mine in my TDI as it boosts like crazy then runs out of stuff and you have no more. My K24 starts to pull and continues to pull more until you redline.

[RabbitJockey]

I know nothing of the saab turbo, but if Trevor gets on here he would probably be able to say if that maybe a good one.

build a hybrid of the saab t3 compressor(40 or 45 trim) with the vw t3 hot side.  assuming your saab turbo is the t3 not the t25 alot of them had.

will be basically the same as ur turbo lucas i think the compressor housing is a little different

make sure u upgrade the intake manifold too


i did a google search if its off an 8v its a 40 trim t3 if its from a 16v its a 45 trim. 40 is a slight upgrade 45 is a good upgrade, 50 trim is the best one that u can actually get a compresso rmap for, its found on some mercedes diesels and volvo 760's  the best as far as t3's go

[alex17young]

I like the hybrid idea. I'm 90% sure the saab is a t3. I measured in when I bought it but I'll check again. If I recall corrrectly Garrett has a generic rebuild kit for many t3's? I'd like to rebuild it myself, Is that a bad idea for a hybrid? does it need rebalanced?... What intake should I keep an eye open for?

[RabbitJockey]

http://www.vwdiesel.net/forum/index.php?topic=31392.0

225 for a rebuild is pretty hard to beat the more complete rebuild kit for a t3 is 100 bucks so for another 100 u get it properly balanced and professionally rebuilt.  Gas intake is a good choice but it requires flipping the exhaust manifold

[TylerDurden]

I'd check the P/N on those Garretts... The one I pulled off a 900 was a t25 -IIRC, they used three different versions.  (Mine is 452068-1S, AKA TB2569.)

[alex17young]

^^good point... I'll check things out tomorrow and report back. Thanks for the feedback fella's

[RabbitJockey]

If it is only a 40 trim I'd lean more towards using the vnt15

[theman53]

http://www.vwdiesel.net/forum/index.php?topic=31392.0

225 for a rebuild is pretty hard to beat the more complete rebuild kit for a t3 is 100 bucks so for another 100 u get it properly balanced and professionally rebuilt.  Gas intake is a good choice but it requires flipping the exhaust manifold

not only that they give you a 12 month warranty, unlimited miles in that time period. It will also come back ultrasonically cleaned and look like new. I will not piss with opening one again for that kind of quality and piece of mind.

[alex17young]

^Sounds like a quality shop, at least its on the east-ish side of OH!...Welp bad news for the hrbrid idea, I found out where the trim is stamped and they're both .42's! The saab charger is a true T3 btw, I'm thinking of using it for some odd reason. It does need a swivel valve and a wastegate though. Correct me if I'm wrong, the trapazoid amanifold/flange of my Garrett stocker is a T3 also even though its smaller than the traditonal t3 flange??? And if I were to flip the stock manifold upside down to clear the gasser intake, wouldnt my turbo be upside down?

[libbydiesel]

You'd need to clock the center section, but that's done easily enough on a T3.

If you have decent fabbing skills and enjoy the challenge of making cool stuff, use the VNT and build a mechanical control.  The performance of a well-controlled appropriately sized VNT is light-years ahead of any single wastegated turbo.  With the VNT15 you can have better high-end flow than the T3 but spool faster than a T2.

[RabbitJockey]

^Sounds like a quality shop, at least its on the east-ish side of OH!...Welp bad news for the hrbrid idea, I found out where the trim is stamped and they're both .42's! The saab charger is a true T3 btw, I'm thinking of using it for some odd reason. It does need a swivel valve and a wastegate though. Correct me if I'm wrong, the trapazoid amanifold/flange of my Garrett stocker is a T3 also even though its smaller than the traditonal t3 flange??? And if I were to flip the stock manifold upside down to clear the gasser intake, wouldnt my turbo be upside down?

.42 is the a/r of the compressor housing, the a/r of the compressor housing doesn't really matter, what matters is the size of the wheel inside a .42 a/r could have any t3 wheel in it which all flow different amounts form 150-300 hp.  the vw flange is a vw only pattern, but the turbo is still a t3, there are many many different variations of the t3 turbo.  if your saab turbo is a 40 trim i'd just use the vnt, it flows more and spools faster than the vw t3 ever could.

saab t3 is either a 40 trim compressor wheel with .48 a/r exhaust housing or a 45 trim compressor wheel with a .48 a/r exhaust housing

vw t3 is a 35 trim compressor wheel with a .36 a/r exhaust housing.  a hybrid of a saab 45 trim compressor wheel and housing with the vw .36 a/r exhaust housing will give u the spool of a vw t3 with the flow of the saab turbo.  i wouldn't bother if its only the 40 trim wheel tho.

[alex17young]

You'd need to clock the center section, but that's done easily enough on a T3.

If you have decent fabbing skills and enjoy the challenge of making cool stuff, use the VNT and build a mechanical control.  The performance of a well-controlled appropriately sized VNT is light-years ahead of any single wastegated turbo.  With the VNT15 you can have better high-end flow than the T3 but spool faster than a T2.

Well I guess I'm up for the challenge, you had a thread on a mercedes forum I think I read a little while ago???

[alex17young]

.42 is the a/r of the compressor housing, the a/r of the compressor housing doesn't really matter, what matters is the size of the wheel inside a .42 a/r could have any t3 wheel in it which all flow different amounts form 150-300 hp.  the vw flange is a vw only pattern, but the turbo is still a t3, there are many many different variations of the t3 turbo.  if your saab turbo is a 40 trim i'd just use the vnt, it flows more and spools faster than the vw t3 ever could.

saab t3 is either a 40 trim compressor wheel with .48 a/r exhaust housing or a 45 trim compressor wheel with a .48 a/r exhaust housing

vw t3 is a 35 trim compressor wheel with a .36 a/r exhaust housing.  a hybrid of a saab 45 trim compressor wheel and housing with the vw .36 a/r exhaust housing will give u the spool of a vw t3 with the flow of the saab turbo.  i wouldn't bother if its only the 40 trim wheel tho.

I dont have a caliper, but eye balling with the tape measure its deff a 40 trim. VNT it is!... Can we multi quote on here? haven't figured that out yet 

[libbydiesel]

You'd need to clock the center section, but that's done easily enough on a T3.

If you have decent fabbing skills and enjoy the challenge of making cool stuff, use the VNT and build a mechanical control.  The performance of a well-controlled appropriately sized VNT is light-years ahead of any single wastegated turbo.  With the VNT15 you can have better high-end flow than the T3 but spool faster than a T2.

Well I guess I'm up for the challenge, you had a thread on a mercedes forum I think I read a little while ago???

I've done quite a few different designs including on a Mercedes 300TD.  Here's a good link to a lot of info:

http://www.vwdieselparts.com/forum/viewtopic.php?f=21&t=11042