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Old 11-13-2022, 10:34 AM
Argess Argess is offline
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It was raining yesterday so I took that left front brake apart. Couldn't find anything wrong with it, but ran the piston out about half-way and then back in to make sure it was working.

Before I took anything apart, I jacked up the front end, put the brakes on hard and then let off the pedal and then rotated each front tire. The right side (I assume is working fine; and I'll explain why shortly) had a very small amount of brake drag. The left side had none.

After I did the work to the left side, both had close to the same slight drag, with the left a tiny bit less than the right.

Today the rain stopped for the morning, so I did a test drive. 0.72 Gs and I know I didn't press the pedal as hard as I could have, but close. The car did not pull to either side.

I'm at a loss to explain this, but it seems that not all the hydraulic pressure is being transmitted through the caliper pistons to the pads. My only thought is the caliper piston seals are sticking and holding it back a small amount. I tested one of my old calipers and it took 50 lbs pressure to move the piston and up to 100 as the psiton came close to beng all the way in. This seems insignificant to the 5000 lbs of hydraulic force, so I'm at a loss. But if the right side was stuck and let go when the car suddenly veered to the right a few days ago, now somewhat evidenced by the slight brake drag and now that I've moved the left side piston in and out hoping to break any bond between the piston and seal, it's working better.

Hard to believe, so I'm not a believer yet!

Not liking these D52 calipers, I have looked into dual piston calipers, but the SSBC ones have a much smaller total psiton area and I don't want less force, and the Wilwood ones are too bulky and won't fit my 15" rims.

That's my update for today... for all those who may be interested.
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