The **DEFINITIVE** other turbocharger choices thread (Garrett, Turbonetics, etc)
08-04-2007, 02:41 PM
#17
Addict
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I run an 824 HP 993 GT2 Evo 3.8 Twin Turbo endurance road race car. I do run Garret BB turbos on an aircooled engine.
For the last 3 years I have to replace both turbos every 4 race hours. Yes I have about 30 sets with 4 hours on them.
I now cool the jacket with oil and it helped a bit but did not solve the problem.
I spoke with one of the garrett race turbo design engineers while overseas and he told me it was definitely the fact that I was feeding the bearings with a -3 line non-restricted that was destroying the seals on the cold side.
I recently actually installed a .060 restrictor and so far so good.
I will know after a couple of races.
The BB turbos oily need a small oil film and max pressure 40 psi not the 75-80 I was feeding it..
LOL why the heck I waited to do it this long is another question.
I wish they made seal rebuild kits I would sell all these turbos on ebay...
Norm
For the last 3 years I have to replace both turbos every 4 race hours. Yes I have about 30 sets with 4 hours on them.
I now cool the jacket with oil and it helped a bit but did not solve the problem.
I spoke with one of the garrett race turbo design engineers while overseas and he told me it was definitely the fact that I was feeding the bearings with a -3 line non-restricted that was destroying the seals on the cold side.
I recently actually installed a .060 restrictor and so far so good.
I will know after a couple of races.
The BB turbos oily need a small oil film and max pressure 40 psi not the 75-80 I was feeding it..
LOL why the heck I waited to do it this long is another question.
I wish they made seal rebuild kits I would sell all these turbos on ebay...
Norm
08-04-2007, 06:41 PM
#18
Burning Brakes
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Originally Posted by DonE
I run a GT35r turbo on my EFI car. I do not use any center section cooling, but they way I get around this it to 1. run -8 AN line to feed the bearings......snip
08-06-2007, 10:19 AM
#20
Drifting
Thread Starter
Originally Posted by Porschefile
Sand_man, if you're shooting for a specific power level, let me know and I can recommend a few turbos. I've seen a few here and Pelican I believe speculate about some slightly smaller turbos like the Gt30r, though IMO those are a bit small for the displacement of most of these motors and the typical 400+whp levels most are looking for. Gt35r's for example usually tend to see perfectly streetable response even on motors as small as 2.5L (I've experienced a few on high rpm 2.0L motors that are still somewhat drivable). I'd suspect a Gt35r with a .82a/r T3 housing or possibly a .68a/r T4 housing should see 1bar by at least 3200 if not just below 3000rpm. I'm still getting used to the whole F6 thing but, on the typical ~2.5L motors I've used these on, usually 1bar comes in at ~3.6-3.7k and the car pulls HARD from there. So what type of headers are you using? To make things easier, there are a few inexpensive aftermarket headers like the GSF ones that already have T4 flanges. I must confess I usually take the lazy way out to avoid fabrication where possible. 
As for mods to my car:
-3.4L Ps&Cs
-OBX headers (no heat)
-Imagine Auto fuel head
-Brian Leask adjustable WUR and RPM solenoid trigger
-SC cams
-Electromotive XDi twin plug ignition
-K27-7200 turbo
-Borla XR-1 muffler
-Tial wastegate with .80 BAR spring
-B&B intercooler
-ARP headstuds and rod bolts
-Totally de-smogged
-965 style compressor by-pass valve (not yet installed)
08-06-2007, 10:25 AM
#21
Drifting
Thread Starter
I have tons of life left in my K27. So this Garrett thing is sort of a long term project for me. I also have an old set of B&B headers that have a hole in them. I plan to cut the heater boxes off, have the holes welded up, and if need be, can have the proper Garrett flange welded in.
I'd be running a Garrett, now, but as I said before, I couldn't get my hands around exactly what was needed to oil one. There was something about running oil through a "water jacket" that didn't sit right wih me.
I'd be running a Garrett, now, but as I said before, I couldn't get my hands around exactly what was needed to oil one. There was something about running oil through a "water jacket" that didn't sit right wih me.
08-06-2007, 10:57 AM
#23
Rennlist Member
Thanks Porschefile, great info.
I just recently completed An EFI conversion on my 3.6T.
I have a conservitave tume for sustained track work.
I didn't care about big HP just wanted quick spool.
My set up is a ITS turbo with a custom T04 E compressor housing,.84 hot side 60-1 wheel- T-4 flange on modified GHL headers. I am using a .60 restrictor at the moment and Blown six IC.
So far dydnoed at 486rwhp @ .8n bar (still need some tuning)
Turbos are hard to drive on the track.
The thing I noticed about this set up as compared to the k27 HF is what Porschefile said about Transient response .car is really lively at partial throttle, and pulls hard and smooth and linear.
This set up was done at ICS performance.com Stamford CT.
fabricating the the plumbing is a piece of cake for them.... (good guys)
I just recently completed An EFI conversion on my 3.6T.
I have a conservitave tume for sustained track work.
I didn't care about big HP just wanted quick spool.
My set up is a ITS turbo with a custom T04 E compressor housing,.84 hot side 60-1 wheel- T-4 flange on modified GHL headers. I am using a .60 restrictor at the moment and Blown six IC.
So far dydnoed at 486rwhp @ .8n bar (still need some tuning)
Turbos are hard to drive on the track.
The thing I noticed about this set up as compared to the k27 HF is what Porschefile said about Transient response .car is really lively at partial throttle, and pulls hard and smooth and linear.
This set up was done at ICS performance.com Stamford CT.
fabricating the the plumbing is a piece of cake for them.... (good guys)
08-06-2007, 07:19 PM
#26
Three Wheelin'
Thanks for those comparison pics Sand_man! I didn't realize that the K27 hotside was so similar in size to a Garrett T3 hotside. Hmm, that's interesting. Does the K27 hotside have a round inlet within the rectangular flange, or is it square like the T3 hotside? After seeing those pics, I'm wondering if it might not be too difficult to fit a K27 variant to a 951. The K26 hotsides are pretty ridiculously small and restrictive. People of course do the K26/K27 hybrids for those cars with the compressor side, but it would be interesting to have the increased efficiency and flow of the K27's hotside/turbine as well. Man, it's thoughts like this that quickly suck my wallet dry! One project at a time is what I try to keep telling myself.
08-06-2007, 08:28 PM
#27
Drifting
Thread Starter
Don't cast your stones. Once and for all, what is difference between T3 and T4? Are these flange dimension differences?
I intended for this thread to be 100% informational, so let's not assume anything.
I intended for this thread to be 100% informational, so let's not assume anything.
08-07-2007, 12:02 AM
#28
Three Wheelin'
The difference is in overall size. I don't have exact dimensions but, T4's are generally quite a bit larger than T3's. Judging by the pics I've seen of K27's, they appear to be closer to a T3 frame turbo. K26's are somewhere in between a T25 and T3 frame turbo.
08-07-2007, 12:19 PM
#29
Burning Brakes
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A T04 has inside dimensions of 2.94" by 1.94". The T03 has ID of 2.31" by 1.94".
The T04 allows 27.2% more volume than a T03. This is a bit deceiving on our 3.3L cars, as the T03 allows more velocity and quicker spool on a CIS car. The T04 is more suited to an EFI application because of the tuning that can be done to take advantage of the larger volume.
The T04 allows 27.2% more volume than a T03. This is a bit deceiving on our 3.3L cars, as the T03 allows more velocity and quicker spool on a CIS car. The T04 is more suited to an EFI application because of the tuning that can be done to take advantage of the larger volume.
08-07-2007, 01:08 PM
#30
Drifting
Thread Starter
And what about water cooling? Boy, never thought I'd mention H2O in 930 thread. Does anyone have pictures or schematics of a plan to water cool a turbo for an air-cooled engine? What type of pump, container, hoses, etc.? Any risk of the coolant finding it's way into the oil system?