danglerb

More power has no upper end if you really crave it, but once the wheels are spinning I don't see the point in a lot of cycles of more power, bigger tires, more power, bigger tires. 350 to 450 rwhp in a 928 should be "plenty" for anything sane on the street.

dprantl

I just keep trying to get a little better, said a little better than befowa

Dan
'91 928GT S/C 475hp/460lb.ft

killav

One thing that some might not realize, is that I was not holding the throttle to the floor in both of those runs (4th and then 3rd gear). I gave it a lot of throttle, but I didn't want it to down shift and ruin what I was trying to show so I didn't slam it to the floor.

The boost response is obviously even better, when pinning the kickdown switch lol.

EDIT: I think I mention that in the video, it's been a while since I have watched it.

killav

Thought I would give an update and data point. The kit has ran flawlessly for well over 2 years. I finished installation in October of 2010. The oil return (scavenge) pump failed on me about a week ago. It first blew the fuse, and the warning buzzer inside the car let me know right away. I was at the car wash, so I figured I just got the pump contacts wet. I replaced the fuse, and everything was fine for about 3 days. Then the alarm sounded again as I was pulling into the driveway. I shut the car off and checked the fuse. Only this time the fuse was fine, but the pump was dead. I pulled the pump apart, and there was no debris that I could find locking up the gears. It appeared that the motor just bit the dust.

I bought a turbowerx "EXA" pump and will install that tonight. This is one of the best pumps on the market for oil scavenging, as best as I could tell. The lifespan of the motor brushes alone are rated for 10,000 hours. This is many many miles. Even if I only averaged 25 miles an hour (easy to do I would think) that is 250,000 miles of use. And the brushes in this motor are replaceable. Should be the last pump I will every have to buy.

The STS pump only lasted about 200 hours by my calculation. The new pump cost $431.00 dollars shipped. Ouch. But, with this being such a critical component to make the car run, I didn't want to skimp.

Tom. M

Interesting data point Mike... I ran the rear turbo on mine for at least 2 years and it was a transplant from another 928 running it for at least a year. Not sure on the mileage over that time, but I never had issues with the STS oil scavange pump (other than being noisy LOL)...

That same pump is currently running on Chuck A's 88.... ...might be worth a look on some other STS install sites (perhaps a Camaro or Vette list)..to see if they are having similar failures..

killav

That's exactly what I did LOL, and the consensus was that the STS pump is OK but not "great", and failures do occur. Some only made it 7k miles, while other guys were claiming 20k miles with no problem....mine made it about 8k.

killav

And I can't be more pleased with the kit. With the proper tuning, the car has been rock solid. The turbo is very "healthy" with no signs of wear (oil seals/bearing play) and still spools very nicely. This pump will make things bullet proof in my opinion.

SeanR

The pump we put on Pele's car lasted all but a week, can't remember what pump it was but I do know it was upgraded at that time and has had no issues since.

killav

Funny, I spoke with Pele before ordering. He has the exact same pump I bought, but his is a Mocal. I think they just re-badge it for Turbowerx. And he has not had a problem since like you said.

The pump that came with Pele's kit originally was also a Mocal, but it was a diaphragm pump. These will not work. I think Pele told me that the pump that Mark used to source became NLA, and so Mark dropped the diaphragm one in the kit not realizing the type of pump it was......

IcemanG17

Hmmm....being that my racer has a battery box removal and LOTS of room in that area.....the rear turbo sure sounds cool...... BUT all that complexity for a gain of maybe 80whp seems kinda pointless....but it sure would be cool

Courtshark

Complexity? Not really all that complex, and I think you can go for way more than 80hp with this set up, especially on a non-street car.

killav

Here are the two pumps side by side. And I took the top side of the STS pump apart to look at the motor and brush's, but I forgot to snap a picture of it. The brush's were worn, but not worn out. I hooked up the pump to my battery, and it runs.

Ali told me to check the relay, but I didn't. It is possible that the pump might be ok. Relay relay relay!!!!!!

I'm still using the bad *** pump though. And will replace the relay.......

hacker-pschorr

Do these pumps run "all the time" or is there some kind of sensor that powers them on?

Just curious since I'm working on adding two pumps to my track car for oil and transmision and I've been researching which ones to use. Different application but essentially doing the same thing.

killav

This is true, and for a race car, I would not go with the smallish 60mm "street" turbo that I have. Go bigger. Anywhere between 67 and 76 millimeter would be my weapon of choice with a slightly higher A/R on the turbine side for great flow at the expense of spool time.....which wouldn't matter as much on a race car kept in the higher RPM sweet spots.


I have been running 10 PSI with this kit for over a year now. And it is probably double that 80hp number.....

In order to do this, I added the following to the base kit:

1. Blow off valve
2. Water/Meth injection
3. Manual boost controller
4. Re-tuned the fuel and ignition maps

killav

It runs all the time. The scavenge pump gets its trigger signal from the positve terminal from the fuel pump. As soon as I start cranking the engine, the scavenge pump starts to run.