Our next race is the first weekend of December. Our master plan has three components. More power, more brakes, maintenance. For weeks I’ve been doing nothing. Mostly because I had to make picknpull trips for parts for the brakes and the power. Ewan is with me all the time now and you have to be 16+ to get into the picknpull. So finally yesterday I got to go.
I got the knuckles and hubs off an Acura CL3.0. I measured the rotors while there. They were 23mm thick and about 11″ diameter. I noticed the calipers had the 25t brackets, which is odd because the rotors aren’t 25mm thick. But we have the Akebono calipers and don’t want 25mm rotors. We had real difficulty finding race compound pads that fit our old Nissins but lots are available for our current calipers.
The removal was hugely difficult. I used my long craftsman breaker bar with a cheater pipe on the end. I used my long socket extension to brace the rotor bolts against the bottom of the caliper. I ended up having to stand on the end of the cheater pipe to get the right side axle nut off. I was totally sure that my breaker bar would break sending shrapnel into my face. It didn’t but I did bend my socket extension. It was about 4.5′ of lever and I weigh… well lets round 200lb for easy calculation. That’s 900ft-lbs! Dang.
Also on the right side the axle just didn’t want to come out of the hub. To get the knuckle off I ended up cutting the inside cv boot and pulling the joint apart. I didn’t have any penetrating oil, which would have helped, so once I had it off I let some brake fluid from the leaking brake line drip on the splines. After I got the left knuckle off the right one was loose enough to hammer the axle out.
So now I have two CL3.0 knuckles. I’ve done lots of surfing and I am convinced that the Stop Tech 12640034SL, which are those on rockauto for the prelude 2.2 dohc (I think the si vtec) are 23mm thick and 11.1 diameter. We’ve had really good luck with the Stoptech Sport rotors. So for Sonoma in December we’ll have rotors with 10% more diameter. That means about 10% less friction force for the same stop, which means less heat, which means slower pad and rotor wear. I’m also going to try to rig up my brake cooling ducts to blow into the inside of the rotor. I think the dust shields can be adapted to help direct the air to the inside of the rotor. At the last race our ducts were directed at the caliper. The pads on that side had about 30% less wear than the pads on the other side. So we know the cooling air helped but we need to get it more evenly distributed.