: Why does my car not want to stop in the wet?



commander112
01-01-07, 06:29 PM
It takes a second for the clamp to bite down almost like there is a bead of water that needs to be shed from the pads/rotors. It is scary for a moment then they clamp down hard. Normal or not? Brakes fine in the dry.

Mark

ewill3rd
01-01-07, 06:41 PM
Stock pads?
Hot, cold?

commander112
01-01-07, 06:44 PM
As far as I know they are stock pads (car bought used). Cold or hot same issue.

Mark

HiTechRV
01-01-07, 06:58 PM
What tires are you running? My later version F1's (the "all season" flavor) seem great in water.

commander112
01-01-07, 08:09 PM
Not tire related. Running winter rubber and I can feel they have adhesion. Definetly brake related.

thebigjimsho
01-01-07, 09:18 PM
Many brake systems will have a period of time to dry out the pad material before the friction heats up enough to clamp down. Are you talking about after driving in the wet without touching the brakes for a few minutes?

I think the V's brakes are more prone to do this than many other factory systems because it is a 4 piston caliper. The clamping force comes from both sides of the rotor so it may take slightly longer to clamp than a
single piston caliper. Just a good reason to take it easy in the rain, I guess.

commander112
01-02-07, 07:01 AM
Many brake systems will have a period of time to dry out the pad material before the friction heats up enough to clamp down. Are you talking about after driving in the wet without touching the brakes for a few minutes?

I think the V's brakes are more prone to do this than many other factory systems because it is a 4 piston caliper. The clamping force comes from both sides of the rotor so it may take slightly longer to clamp than a
single piston caliper. Just a good reason to take it easy in the rain, I guess.


Exactly what I am talking about.

ewill3rd
01-02-07, 07:12 AM
I had a car that refused to stop cold, especially if the temps were below freezing. The brakes worked great after half a mile but the first stop was the scariest stop of the day, almost killed me more than once.

Different brake materials have different characteristics. I'd say that the water is cooling them below an efficient range and that coupled with the moisture itself is degrading your stopping power at times.
You could try to switch brake materials (depending on what kind of driving you do most) or just get used to the phenomenon and take it into account in wet weather.

jspridge
01-02-07, 09:49 AM
How is the brake dust on your car? If it's minimal, then my guess would be that the previous owner changed the stock pads for Hawk to reduce the dust. My brakes have exhibited the same "crap your pantsness" when driving in rain that you describe since I switched to Hawk pads.

commander112
01-02-07, 02:53 PM
Thanks everyone.