The shims are primarily use for noise reduction. Actually I love driving on the street with the XP10, I just hate the dust it produced and the noise. I wonder if shims would help

Hallelujah!
 

It worked!

No Ice Mode!

I was at the Summit Point Main Circuit on Friday and my Z withstood multiple stops from 125 mph without ice mode occurring on any of my four track sessions. The weather was hot and sticky with the track rapidly heating up as the day went on.

If you remember, I was at S.P.M a couple of weeks ago and encountered ice mode on three occasions in cool weather.

The difference was:

1. I switched from Porterfield R4 brake compounds to CarboTech XP10 in front and XP8 in rear (which I think helped but other members have experienced ice mode with CarboTech pads). Don't get me wrong, these pads are the best I have ever used, anyone want to buy a set of Porterfields? One more thing...YOU NEED CARBOTECH PADS! However, I suspect ice mode is more related to heat then pad failure.

2. Castrol SRF brake fluid. This stuff is $80 per liter. That was not a misprint! It has a insanely high wet boiling point.

3. Brake cooling ducts. I suspect this is what really solved the ice mode problem. My ducts are based on ModShack's forced air fang ducts. Using that as a staring point, you need to remove all the side radiator baffling to route the tubing and cut material away from the plastic wheel well covers to rout the 2.5 inch brake hose. On the passenger side this required dremel tooling a portion of the coolant/washer fluid support bracket. Zip tie the end of the tubing to the lower portion of the shock absorber pointing at the caliper. Now bolt up your wheels and check for rubbing. If you have rubbing simply take your foot and push on the tubing to flatten it out.

In conclusion, whatever created the ice mode problem was probably a result of the heat caused by a total lack of air flow to the inside of the wheels. Fix that issue and I believe its problem solved.

You sure you weren't feeling brake fade? I hit ice mode in autox today without overheating my pads at all.

Yeah I hit ice mode on moderately warm brakes. There are too many changed variables to label it as one cause. You changed brake compounds on both front and rear and that could have played a HUGE role! I am glad the problem is solved for you but the verdict is still out as to what is really causing ice mode and I am pretty sure it's not heat related but... I could be wrong.

had viscous amounts of smoke coming off my brakes today at Spring Mountain and no ice mode! I credit the ridiculously stiff springs (#1100) which I love!

so travis changed springs and problem solved... and resipsa changed pads/fluids and added brake coolers to solve the problem...

So... if that's the solution, then what was happening was one wheel would compress hard, allowing one of the other corners to lift off?

I took temperature readings yesterday at the auto-x but the day was cooler and the wind was strong. No ice-mode today. Peak rotor temperatures were a mild 350F and calipers were only 220F. There were some ABS skips but that was purely because of the sudden weight transfer.

Interesting results by both Travis and ResIpsa.

What difference did you notice the most with the new springs Travis other than a stiffer ride?

don't want to get too far off-topic, but for a dedicated track car 18k/16k seems like the place to be... car was much grippier and I was able to hold higher lateral g's with more stability... it gave me the confidence to carry A LOT more speed into high speed corners and I knew exactly how much grip i had left... and knowing where we are relative to the limit (and side of the track!) is what it's all about

How high do you think you could go in a streetable car before it starts to break my back? I don't do that many highway miles in general, but need to be able to drive a few hundred to the track.

for this car, I'd guess prob 14/12 or thereabouts... 12/10 was fine on the street for me... 18/16 would be pushing it, I think... btw, as you may know, what matters is "effective wheel spring rate"... wheel rate is determined by the geometry of the suspension and the spring rate... so, if you get input from other car types, their feedback may not apply

Anyone tried leaving the front pads alone and only upgrading the rears to try and adjust the brake bias? We had to do this in my miata because of excessive lock-up. It mightbtrick the computer into laying off the ice modeandtaking some of the stress and heat build-up off the front brakes.

I tried using a more aggressive pad in the rear only but it didn't help other than making the rear lock up prematurely. The stock bias already favors the rear somewhat and then it uses ABS to dial out rear lockup.

Cross-post from my journal... this setup is compatible with the OEM fascia and draws air from outside the 'fangs'

And the long-awaited brake cooling setup! If you're interested in this, and we all should be given how inadequate the air flow is on our front brakes, suggest you contact Chet at SRD Performance of Tempe, AZ Ph: 480-317-0090 or e-mail: sales@superiorracing.com

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