Garrett GT1752 for a B3?

[Christ]

double post

[Advancedynamix]

I believe this is what you need.

http://www.turbomaster.info/eng/catalogs/model.php?base=garrett&pagina=GT17

[Christ]

Thanks! That should do the deed.

[DON SVO]

Detonation will end the party for sure, but can be avoided with proper tuning. My guess would be that the factory head will not allow more than 200hp without major modifications. The intake ports and valve size will be a restriction long before the gt17 runs out of juice. When the engine can't consume the air your trying to force into and out of it you'll see a drastic rise in iat, resulting in higher combustion temp, then detonation then chunks of piston being puked out. My guess is somewhere between 190 to 220hp at around 6 grand with about 20-25 psi, if tuning is spot on and the turbo system is properly designed. Someone try it so we can see for sure! Lets test the BMEP of a stock b6. Lol

Pretty much! That head (in stock form) can only move XXX of air. Cranking up Lil' Weezy to try and hit 200hp would put you around 2.5 bar, or around 22-24PSI. Get that turbo thrashing around @ 190K and it'll detonate, probably at peak torque to boot.

[iceracerdude]

Though I no longer have the compressor map for the 1752 and 1752s, I can tell you that it is sized correctly for 1.3 liter 8 valve 4 cylinder. They are known to be a huge restriction on the Saab engine ( which should have come with a gt2560). SAAB used the tiny 1752 to make their engines feel more like a large displacement N/A 4 cylinder. It's comparable to a kkk ko3. It has also been used on diesel engines up to 2.0 liters. (don't quote me on this, but I think VW used this turbo as well).

+1 on all of this ^ and yes, The K03 was used on the Audi/VW 1.8 dohc 20 valve!
My K03 is making boost on my 8 valve B6 @ just 2,500k...hadn't expected that.

[Advancedynamix]

+1 on all of this ^ and yes, The K03 was used on the Audi/VW 1.8 dohc 20 valve!
My K03 is making boost on my 8 valve B6 @ just 2,500k...hadn't expected that.

Yeah, the K03 was a staple of the VW turbo effort through much of the last two decades, but I meant that I think VW also used the gt1752. They were testing it on the new TDI when I was still working with Garrett, haven't paid much attention since then. The K03 is a great turbo for the b3 and B6 as well (as iceracerdude has already stated) but they are just a little harder to find in wrecking yards (at least around here). A friend of mine has had very good luck with the k03 copies from eBay. He has installed them on a dozen or so poor college kids 1.8t VWs without any problems.

It is also possible to find gt17 turbochargers with a ball bearing center cartridge. Not sure exactly what cars came with them, but I know some Saab 9-3 and 9-5 cars were fitted with them as replacements when the original turbocharger failed under warranty.

[Christ]

What are people using for a turbo manifold? Just welding a flange to the OEM manifold? I have a spare, so I could probably feasibly do that, but it seems like there'd be something that flows much better easily available? Then again, it's just a B3... not like it's a huge air mover or anything...

[Christ]

Also, how will the stock auto trans hold up to maybe 4-5 PSI? I don't want much, cuz I'm not looking to upgrade the B3 much to do this... just a HMT quickie.

[TominMO]

I posted the below info/question in another thread, hoping to learn more about turboes, but there was no reply. Any (informed) opinions?

From the Garrett website (TurboByGarrett.com):

Model.......Motor displacement......HP
GT1241.....0.4 - 1.2 Liters...........50 - 130
GT1544.....1.0 - 1.6 Liters...........100 - 150

I was looking at this a few months ago, and decided one of these would be best. A turboed B3 should make about 95 HP, so the 1241 looks appropriate. But the 1544 is right in the middle of the displacement range, so that one looks right too. Wouldn't anything larger like the 1752 just be overkill? Also, isn't it true that the smaller the turbo, the less the lag?

Also (new question), how would the driving characteristics be different for these three turboes?

[Christ]

The 1241 is good for (IMO) 1.0-1.5 liter engines with low output already. It'll spool almost instantly on a 1.5L, and spool pretty fast on a 1.0. The smaller the turbo (generally) the quicker it'll spool (RPM wise) because it requires less energy to compress the smaller air volume.

The .4L displacement figure is probably for "dedicated" work engines that are generally always running at high RPM, with variable load. Ideally, according to Honeywell's figures (Garrett), I should be using the 1544, but I've yet to actually see one in the wild, and that's going to give the "instant spool, gradual increase" feeling of a factory setup, which is not far from what I want, but slightly low-end.

I'm pretty much looking to be on/off boost at cruise speed, so that when I'm hitting hills and such, there isn't as much "will I make it?" going on.

Those figures are nominal, based on the "reasonable" air output of each turbo setup. The 1752 "Can" make about 230-240 HP reliably, and I never expect to make even close to that without 100hrs of head work and a complete work over. Based on what I've read in other people's experience, the 1752 cartridge will spool at 2500 or slightly less on a 1.3 that normally makes 45ish HP.

Really, it's not going to cost me much of jack to do this, cuz the welding will be done by my ex's father, and everything else is basically bolt-together stuff and some piping/oil lines, so I'm pretty much gonna do it and let everyone know how well it works out. If I blow the trans up, tough. I've got a 5 speed that this car is crying for anyway.