Best Brake Fluid

[Don Middleton]

Cooked the ATE Super Blue brake fluid in my 911SC during the first session in last Sunday's DE. The fluid was too old. Now, I know to replace it before each DE.

But, in replacing the fluid, I wonder if there isn't something better, i.e. higher boiling point, etc. I know they are available, but are they worth it and will they work any better?

[kary]

If your Blue was old then chances are it had a lot of moisture in it. That is what caused it to boil along with a lack ofr cooling at the stadium parking lot. There are some choices other than Blue (Gold) but they are not going to help that much in that situation.

I use blue on big tracks and do not have an issue boiling.

[Steve Grosekemper]

Don,

The stadium DE's are very hard on brakes. Lots of heat into the brakes and very little cooling air. Fresh ATE Blue should be more than adequate as far as fluid is concerned.
Fresh is the key!

You need to work on cooling.
-Brake pads must be thick. Thinner pads transfer heat into the caliper.
-Remove the backing plates from both front and rear rotors.
-If the fluid boils after these steps look into brake coolers. Ask others with 74-89 911's what systems they use and like. There are several options out there from simple to elaborate in operation and cost.

[Dan Chambers]

Don:

Many of us do a quick brake-bleed each time we change our tires from street to track. If you change tires before any events, concider investing in a Power Bleeder, or similar bleed-assist device (I'm sure Kary has 'em, or Dieters, or Black Forest, etc), and do a bleed a couple times a year.

I figure, a can of Super Blue runs about $10.00 to $20.00 a piece. If I go thru a can a year, I'm stoked!

Typical routine for me when prepping for a track event (Big track or small):

1) poor fresh super Blue in Power Bleeder
2) lift hood; attach power bleeder to brake reservoir (on Monica's 912, pinch off pressure by-pass hose so fluid doesn't leak into left wheel well)
3) pressurize brake system to 8 + / - psi for bleeding
4) loosen wheel bolts, lift vehicle on right side
5) pull rear-right wheel, bleed brakes with 7mm wrench, tubing and bottle from Gateraide with whole/tubing in lid
6) Put on track wheel and hand tighten
7) pull front wheel; bleed brakes with 8mm wrench & bottle assembly; put on race wheel
8- lower vehicle and torque wheel nuts to 91-Ft. Lbs with torque wrench

Now go to other side of vehicle and repeat the process, starting with the rear tire. You should do the front left tire last, since it's under the reservoir, and seems to collect the most gunk. (I know it's better to do a bleed from rear to front, starting with rear-Rt., rear-Lft., etc, but with near-monthly bleeding, it doesn't seem as critical.)

For the extra 20 minutes of time to process the bleeding, it's totally worth the firm peddle and confidence you have when at the track, and it won't shorten your track-day!

Hope this helps!

[ajackson]

Dan: that is a very good suggestion. Now that I am occasionally switching to track tires I think I will do the same.

[Don Middleton]

Kary/Steve/Dan...thanks for the feedback...lots of good stuff...glad I asked!

[pdy]

Don:

Sorry to hear about the fluid issue. I've been there many
times, with many different cars, not just the 911SC!

I also use the Blue, and find frequent bleeding/replacing is
really important.

One item Steve mentioned, and I will emphatically concur with
is pad thickness. I would also suggest that different pads
can also make a difference in amount of heat transfered,
even if the thickness is the same. Pad selection also has a
lot to do with the pedal feel, and overall brake performance.

I am currently using Hawk Blue which I feel work really well,
but my car is biased towards tracks. These pads seem to allow
me to go longer between bleeds, while affording consistently
strong braking and great brake pedal feel . I'm sure there are
many other comparable pads, and perhaps some which might
suit your particular needs better.

Like you are doing on the Forum, I recommend you continue to
talk to folks - both drivers and shops/retailers. Then try out
something that seems like it would be a reasonable fit for you.
I did this, and found a BIG improvement over the factory stock
brake pads.

BTW, I do not run any brake cooling or ducts, but I have removed
those ghastly dust shields on the inside of the discs.

Best,

Paul.

[Tim Comeau]

Just wanted to revisit this thread and share some more experience with a fellow PCA'er.

The ATE Super blue is great with a dry boiling point of 536F. The ATE Gold is the same fluid, just a different color. Why a different color? So you can tell when you've flushed out all the old blue fluid. Next time you flush, use the blue again. "Flushing" the whole system is not the same as "bleeding" the corners.

Ducting for the 911's: The best system I've found is the one still sold by OG Racing. They use the old Al Holbert molds which duct a 3" hose directly into the eye of the rotor. Make sure you get the plates that keep air from spilling out through the wheel spokes. The AJR product and ducting is smaller. The air then exits out the edge of the rotors as Porsche planned. I used this ducting for years with my stock, steel, pea-shooter 1976 calipers without issues.

For sure, I would remove the "splash guards" from the inside of the rotors, front and rear, (recycle them) as these reflect radiant heat right back at the friction surface of the rotors. We don't drive through mud, slush, snow, deep water, here in San Diego do we?
Nope. We want that rotor to act as a big heat sink during braking (we're trading speed for heat, right?) then disipate it as quickly as possible so the heat doesn't build up and get to the fluid in the calipers.

I also use the Hawk Blues and get good stopping power out of them. Good initial bite, good torque, good consistency.
Good Luck!