2000 ACR and Carbotech Brakes

[Viper Blade]

I was trying to balance the stock brakes on my ACR a little better with brake pads by softening the grip on the front and increasing the rear via pads. In stock form and stock pads the fronts lock easily and try to ruin my $20k hood. Searching brought me to the solution to use AX6 on the front and XP8 on the back however being a dufus of the highest degree at time of course I ordered them backwards.

I did not realize my error until I had the XP8s on the front and bedded in. I'm thinking I should use another set of XP8 on the rear or XP10 to accomplish what I originally set out to do. The car is realistically street driven 99% of the time except for spirited club rallys. Someday though autocross is not out of the question. I just have no time to do so at present.

Just looking for experienced opinions from those who may have some experience with these pads.

AX6, XP8 or XP10 for the rear. I'm thinking the XP10 may be best to accomplish what I set out to do in the first place

 

[mjorgensen Woodhouse]

You should NOT use a higher torque pad in the rear then the front, the front of the Viper does 80+% of your braking and changing that bias to the rear with a grippier pad compound will get you back wards faster then you can say guard rail. The higher number XP series pads will take more heat (that the front brakes generate) and fade less then the lower numbered XP's. For dual duty you should use the XP10 front and XP8 rear, maybe even the AX6 in the rear (although thet AX6's are NOT a track worthy compound) depending on your cars setup.

For a track day only car the XP12 in front is the better choice and the 8 or 10 in the rear. I would run the 8 back there in my opinion though because I have seen nasty rear wheel hop under hard braking with a much grippier pad then the XP8. On cars with ABS it will actually engage the ABS sooner to counter the rear locking up long before the fronts would, which lengthens the distance to stop even further.

 

[Dom426h]

FYI:
Viper Blade is talking 99% Street
mjorgensen is talking 99% Track (his advice is good yet irreverent to the OP's situation. Except for the guard rail comment)

common sense tells me that running an autocross compound on the front and track pad on the front is a BAD idea for the street. Why?:
AX compounds work(stop) in a lower heat range
Race compounds work in a higher heat range.
Now picture yourself driving down the freeway. All of your pads are at ambient temp. Something causes you to have to make an emergency stop. The rears like the cold temp and bite hard. The fronts dont bite at the cold temp. = Guardrail(like MJ said)

Blade, Your Viper has an inherent braking issue: Four pistons up front. One on the rear(with a prop valve that further limits it)
Fix this problem first. Then worry about what brake pad compound you want to run.
If you dont have the budget to do a complete aftermarket balanced brake kit or Gen3 retrofit upgrade(like me). Then your best bet is to get some Tom's40mm calipers on the rear. Is is just a stock caliper bored out with a bigger piston. Next step is to remove you proportioning valve

 

[Viper Blade]

All, sorry I couldn't respond sooner. With the economy as it is I work out of town for extended periods and company computers are monitored for private use. Also at this time I have to watch finances. Even though I am working my company is not reimbursing me for rent etc. ***** but it beats the alternative for now. I'm a EE for our utility in CA. Yes I do drive it street, just once has it been to an autocross. I probably won't full track it as it's 12 years old, I've had it for 8 of those, and in good enough condition that most people who see it think it's new. Hence I like to maintain originality, for now in regards to brakes.
It seems then that I should just go ahead and purchase the XP8 on the front and AX6 for the back. That is my understanding in regards to your response. Am I correct? I do appreciate very much how all of you reply so quickly and professionally and my apologies again that I couldn't respond sooner.
Regards VB