blake

(Per Holger's request on another thread...)

This is an excerpt from the Tech Q&A section of the PCA's July 2007 edition of Panorama. Joel Reiser, 911 Technical Committee Chair, responded to this question:

Q: I am planning to use my 2004 GT3 for more track events in the next year. Do I need to decrease the time or mileage interval for maintenance items? Currently, I change the oil and flush the brake fluid every year or 10,000 miles. I also follow the factory recommended maintenance schedule. Is every six months or 5000 miles overkill if I drive about 7000 miles a year and do 12 to 15 track days? I am having the GT3RS motor mounts from Carnewal and ERP rear bump steer kit installed soon. What exact alignment settings do you suggest I start with for mostly track use?

Reiser: Yes, if your budget allows, it is always best to speed up the maintenance interval on a car that sees track use. The top guys with the GT3 Cup cars change the oil and flush/bleed the brakes before or after every event. Six months/5000 miles is not overkill in my opinion for a GT3 street car, and maybe a little more often than that might be good. If you run Catrol SRF brake fluid you won't need to flush the brakes that often, but with any normal brake fluid you might.

Keep a close eye on the brake wear, both rotor and pad. Do not assume the pad wear is even. Those big six piston calipers can give a lot of tapered wear sometimes when you don't expect it. It is best to actually pull out all of the pads before or after every event and measure the pad thickness remaining. You want to do this as much to get a sense of how fast they wear as to check for when to replace them. Check the rotors for cracks. Small cracks are normal, but throw the rotors away if the cracks connect the holes or reach the edge of the disc. The pad will jam in a crack at the edge, and spin the car.

I like to "flip the burgers" to even out the pad wear, while some other people insist you keep them all in the same location until you throw them away (which will be sooner obviously if they are showing tapered wear). The reason to flip them is that, especially with the better race pads like Pagid RS14 or RS15 grey, green or black, or Performance Friction, you will start to see grooving on the rotors, aka "rings of Saturn". The pads will be conforming to he grooves. That is called "bedding in". If your rotors have evidence of grooves, don't flip the burgers. If you do, or if you lose track of which pad went where, take it real easy for as many laps as it takes for the pads to bed in again.

If your rotors are showing "rings of Saturn," but with only normal light to moderate cracking, you can run new pads, but again you will need to take it easy to bed in the new pads to the old rotors. Most people don't bother, since the stock GT3 steel rotors are relatively cheap, and they will crack before they run out of thickness.

For alignment, start with stock toe, and as much camber as your tire type wants. For street tires, start with no more than two degrees all four corners. For DOT-legal track tires, I would probably start with 2.5 or three degrees all four corners. The tune with tire temp readings and shoot for even tire wear all the way across the tire.

-B

enthusiast

Thanks for postiing this.

How about the fuel filter? The book that comes with the GT3 only mentions replacing the fuel filter at 60,000 miles. It does not list a time limit like they do for engine oil and some other items.

mooty

i do about 15k miles total a year.
i put in new fuel filter every year. it's not much money, so i just do it.

996FLT6

Hey Mooty please tell me that's not one of your houses : (. Mike

enthusiast

Any do it yourself tips for this task on the 996 GT3? I have changed many different fuel filters but not this car's. Looks like a simple (unsafe looking) rubber hose on one end of the canister and a more proper fitting on the other.

mooty

it's my neighbor. my is only a 1500 sq. ft. dog house.

mooty

sorry, all i know is how to change oil, filter, pads and rotors.
my mechanic does the plugs and fuel filter.

Holger B

Blake, thanks for posting. It's good to know that I'm doing the right thing.

Interesting that there's no commentary on tranny oil. I've been changing mine annually.

JMcD

Holger B,
What trans oil are you using in your '04?
Jack

Holger B

I haven't done it myself, but it's been changed at both the dealer and at an indy. I think the indy used Mobil 1, not sure about the dealer. It shifted more smoothly after the indy oil change vs the dealer. Lots of commentary here in past threads regarding which oil is best to use due to the LSD, etc.

Phokaioglaukos

Very true, and it almost caught me out. About a ¼" difference between the leading and trailing edge of my Pagid RS-19s. Of course it's easy to see the trailing edge, which wears less.

LVDell

I'll be using the Mobil 1 Delvac here shortly for the first time. Right now I just have the factory fill original oil.

Here is what I just ordered:
MOBIL DELVAC

Or for those that don't want to click the link


Mobil Delvac 75W-90 gear lube (1 gallon)
The replacement for the Mobilube 75W-90 SHC gear lube. Delvac has been market name used in USA towards the semi/fleet maintenance market segment. Hard to find in gallon containers, but we stock it.

Original fill in 996/997 GT3/Cup cars, and GT3Rs. Works well in all 901, 915, G50, G96 gearboxes. Used extensively in Porsche Motorsport products in every grueling test there can be LeMans, Sebring, Daytona, etc. We also use it in our service department in all street and race cars. Works in cars with or without (LSD) limited slip differentials.

Great lube, surpasses all others in research and development. Mobil Delvac 75W-90 is a fully synthetic drivetrain lubricant engineered to meet the most demanding extended drain and OEM warranty requirements. These products are designed for use in heavy duty drivetrains that require gear lubricants with excellent load-carrying capability and where extreme pressures and shock loading are expected. The state-of-the-art technology in Mobil Delvac 75W-90 delivers unequalled performance for low and high temperature applications, including outstanding oxidation stability, wear protection, corrosion resistance, improved shear stability, extended service capability, and excellent fuel economy

Holger B

Dell, let us know if you notice any difference using that stuff.

Thanks.

LVDell

Sure will.

Chris L.

I have one event under my belt after changing with the Mobil Delvac.

No difference noted good or bad. More to follow.