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Who's using a GT35R B.B Turbo?

Old 07-05-2006, 05:19 AM
  #16  
ProtoCab
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WOW, you've gone all out to cool that sucker. Not sure if it's required though. People have had good success running them oil cooled only and running oil through the water passages.

Which part of Aust are you in?
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Old 09-06-2006, 07:34 AM
  #17  
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Mondragon, how is your GT35R performing on the Schnell headers?

My car is purely street and I'm now considering a GT30R for optimum spool and torque for street use only.

A 600HP GT35R may be a bit of an overkill for a pure street car that only sees occasional full boost, I think.

What do some of you other guys think?

Here are the specs of the GT30R:

http://www.turbobygarrett.com/turbob..._700382_12.htm

NOTE: I only plan to run 1.0-1.1bar. My engine is a Carrera base, with 930 P&C's and GT2 EVO CAMs. I want FAST spool and gobs of torque down low
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Old 09-10-2006, 09:13 AM
  #18  
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Originally Posted by DonE
One bar of boost was around 3600 rpm, .4 at 3000.
DonE, with all due respect to your car (I reckon it's AWESOME), I would have expected the GT35R to spool up and reach full boost of ~1bar earlier than this on your motor.

Have you tried, or ever thought of trying the slightly smaller GT3040R? It flows the same (approx 600HP with the GT40R compressor), but has a GT30R turbine, which should reach full boost earlier than what you're seeing.

Just a thought. I was tossing up between the GT3040R and the GT35R, but I think I'll try the smaller GT3040R since my car is purely street and I want a very quick spooling setup.
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Old 09-10-2006, 01:12 PM
  #19  
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Originally Posted by Mondragon
i have just had my engine rebuilt with a whole heap of things including a GT35R BB turbo. it will be fed by a set of schnell extractors. i hope it does what i hope it is supposed to. i have added a water cooling circuit, which comprises of a suzuki 250cc motor cycle radiator, thermo fan, custom made cowling and davis craig water pump mounted in the left hand rear wheel arch. if any on is interested i can send some pictures.
Alex...
Alex, I would love to see your set up with pictures, please do post.
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Old 09-10-2006, 03:31 PM
  #20  
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GT30R is smaller than the 60-1 and K27 HyFlows..
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Old 09-10-2006, 05:32 PM
  #21  
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Kevin, I have your K27HF2 in my soon to be completed 3.4 930 with GT2 Evo cams 72lb/hr Siemens injectors, B&B headers, fabspeed exhaust, Motec M600 EMS, and all the usual trick stuff, all things being equal which turbo would spool faster and provide more sustainable torque numbers.
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Old 09-10-2006, 06:10 PM
  #22  
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What are the comparisons. You can't say quick spool and want a larger air output in the same phrase. Your HF2 is 65mm VS a GT35R's 61mm.. The smaller the rotation assy the faster the spools.. Yes, one needs to factor the A/R of the turbine housing..
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Old 09-10-2006, 09:48 PM
  #23  
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Originally Posted by Kevin
GT30R is smaller than the 60-1 and K27 HyFlows..
Yup, I'm aware it's smaller, but the GT3040R has the same compressor as the GT35R. Should be a good street only turbo, for quick "get-up-and-go" with good top end too.

Kevin, can you confirm if the KKK's have a T3 style inlet flange?
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Old 09-10-2006, 10:10 PM
  #24  
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You mean the GT3082R.. Yes it has the Euro flange which is similar to the T3..
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Old 09-10-2006, 11:06 PM
  #25  
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Originally Posted by Kevin
You mean the GT3082R.. Yes it has the Euro flange which is similar to the T3..
Sorry, yes, the GT3082R (AKA GT3040R).

I already have a K27HF on my car (the older/original one with the 2-3/4" comp inlet), but I'm looking at going to the GT3082R.
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Old 09-11-2006, 07:23 AM
  #26  
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IMO the Gt30r is a little bit too small for your motor. What are your power goals? Why not just run a Gt35r with a .63 exhaust side. It will spool up fairly quickly, though it will limit power on the top end quite a bit. With a .63 you might run into surging issues though. If you were to do a Gt3076r, I'd suggest at least a .82ar exhaust or larger due to the displacement of your motor. Just FYI, people are getting 1bar of boost at ~3k rpm on 2.5l 951's using the Gt3076r w/ a .63 exhaust.

The Gt3082r (aka gt3040r) is a bit of a compressor/turbine mismatch. I've seen and known several people that have used these turbos on various other turbocharged cars (mainly Japanese small displacement 4cyl's). Apparently because of the mismatch of both wheels, you only really get about 200rpm quicker spool than a gt35r with the same exhaust housing. If you don't want over 500rwhp, it should be fine though it will struggle to make power above 500, and will probably max out around ~550-575rwhp judging by the numbers I've seen on various other cars.

If the turbo spools early, the party is over early. Big turbos are where it's at! Here's my new mod for the month:



It's the one on the left (Precision T71, .81 exhaust). For comparison, the one on the right is a Vitesse stage 4 (it has a Gt35r 61mm compressor wheel).
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Old 09-11-2006, 10:44 PM
  #27  
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Thanks for your response.

My goal is to have a quick spooling street car. I have a cabrio and I don't track it or take it to the drag strip (clutches are expensive).

As for my HP goal, anything between 500-550 at the flywheel is enough for a street car. The GT3076R seems to match this application nicely. I was looking at the 0.78 A/R divided turbine housing, to suit the Schnell headers.

Personally, I prefer the turbo to come on earlier with a fatter powerband, since it's a street car that sees occassional full boost runs. Not after bragging rights or a HP shoot-out vehicle. Just a very streetable car with quick get up and go. It's my daily driver!

ATPTurbo recommended the GT30R, as opposed to the GT3040R. They say the GT30R will spool up 400rpm's quicker than the GT3040R. You are correct, the GT3040R has a compressor:turbine mismatch. I think I'll go down the GT3076R route. $1300 delivered to my door WITH all appropriate oil feed line, restrictor & fittings
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Old 09-11-2006, 11:37 PM
  #28  
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Originally Posted by ProtoCab
Thanks for your response.

My goal is to have a quick spooling street car. I have a cabrio and I don't track it or take it to the drag strip (clutches are expensive).

As for my HP goal, anything between 500-550 at the flywheel is enough for a street car. The GT3076R seems to match this application nicely. I was looking at the 0.78 A/R divided turbine housing, to suit the Schnell headers.

Personally, I prefer the turbo to come on earlier with a fatter powerband, since it's a street car that sees occassional full boost runs. Not after bragging rights or a HP shoot-out vehicle. Just a very streetable car with quick get up and go. It's my daily driver!

ATPTurbo recommended the GT30R, as opposed to the GT3040R. They say the GT30R will spool up 400rpm's quicker than the GT3040R. You are correct, the GT3040R has a compressor:turbine mismatch. I think I'll go down the GT3076R route. $1300 delivered to my door WITH all appropriate oil feed line, restrictor & fittings
Oh, I was just kidding about the big turbo thing! That's the route I'm taking as big turbos and dyno queen numbers are what suits me, though responsiveness is great too!

Honestly, I'd just do the .82 non-divided housing. Your engine has a large enough displacement that a divided exhaust housing on a turbo of that size really isn't necessary. It will spool up fast enough as is, and you'll probably see full boost at 3k or lower even with a .82. I just tried to find some pics of the Schnell headers online. Are you sure they have a divided T3 flange? I would think it more likely that they have a divided T4. Just FYI but the .78 divided housing ATP offers is a T3 housing.
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Old 09-13-2006, 03:20 AM
  #29  
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All the aftermarket headers for the 930 (GHL, B&B, Schnell, GSF) use a normal KKK/T3 style flange. The only people who make them with T4 flanges I believe are BIG HP fabricators, like Essa-Tech, Marco Menzie etc...

Yup, the Schnells have the divided T3 flange, so I'm matching that to a GT35R with a 0.78 A/R divided turbine housing, for better spool, at the expense of a bit of top end HP. The compressor will still flow up to 600HP, but the divided T3 inlet should make it a little more responsive.

DonE's car, which I believe is a well tuned 3.4 with 8.0:1 C/R spools his GT35R (with T4 turbine housing) to full boost at about 3500 I think, from a previous post of his. I want mine to spool a bit earlier since mine is purely street. I have GT2-EVO CAMs too, so that should help the turbo spool nicely!

I'll let you all know what the end result is
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Old 09-13-2006, 03:24 AM
  #30  
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Here's a pic of the Schnell/GSF headers:
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