Squirrelly rear end in rain - new tires, new wheel bearing

[JackG]

There's something that no one is talking about...

The Boxster has wide tires in the rear. Wide tires and wet roads simply don't go together. The same wide tires that give us great cornering traction in the dry penalize us by hydroplaning much quicker than a skinnier tire would in the wet. Boxsters just aren't very good in the rain.

Originally Posted by JackG

There's something that no one is talking about...

The Boxster has wide tires in the rear. Wide tires and wet roads simply don't go together. The same wide tires that give us great cornering traction in the dry penalize us by hydroplaning much quicker than a skinnier tire would in the wet. Boxsters just aren't very good in the rain.

Jack, we did several runs last year at the Dragon in the rain. The Boxster was simply amazing on the wet roads.

[blinkwatt]

Originally Posted by bmussatti

Jack, we did several runs last year at the Dragon in the rain. The Boxster was simply amazing on the wet roads.

It's also part of the reason why my Boxster spun out...I've hydoplanned several times in heavy rain.........

We drive sports cars.....use at least least high performance tires,most of us run extreme or max performance summer tires....it's not going to be as fun to drive in the rain as a corolla,camry or bug.

Originally Posted by blinkwatt

It's also part of the reason why my Boxster spun out...I've hydoplanned several times in heavy rain.........

We drive sports cars.....use at least least high performance tires,most of us run extreme or max performance summer tires....it's not going to be as fun to drive in the rain as a corolla,camry or bug.

Blink, I think your biggest culprit was the fact you did not have PSM.

[Benny986]

wheel hop: shocks/springs

the rear end: i would say tire pressure and the mismatch.

if it was dry, then i'd say its alignment. toe it in some, then when you get matching tires up front, and figure out the tire pressures, then you can bring the toe back out to the orig spec.

[2000SoCalBoxsterS]

You can not mismatch your tires. As per the PCA.org tech site here is what the Boxster expert Scott Slauson says in answer to a members question:

Q: In looking at the diameters for these tires, they are 23.4 inches and 25.1 inches. Is this going to be a problem? I am planning to use these tires for Drivers Ed events.

Ans: "The one thing to consider though is when changing tire sizes to keep the rolling circumference even on both front and rear tires. The ABS system will shut down if the circumferences are too large of a difference. Those sizes will not work with the ABS system on the car. You will get a speed deviation that will shut down the ABS and turn on the light."

[JackG]

Originally Posted by bmussatti

Jack, we did several runs last year at the Dragon in the rain. The Boxster was simply amazing on the wet roads.

I've driven mine in the mountains on wet roads as well. It was fun, and performed well. However, the OP in this thread wasn't driving on a wet road, he got caught in rain. That carries the probability of standing water at highway speeds, something I doubt your Dragon runs encompassed.

Hydroplaning doesn't happen when the road is merely wet, it happens when there is some water depth... something for the tire to get on top of. No reasonable person can argue that a wide tire is as good or better than a skinny tire at resisting hydroplaning. A Boxster is a relatively lightweight car with some pretty wide high-performance summer (dry weather) tires on the rear. A perfect example of a hydroplane waiting to happen.

At 70mph on the expressway in a downpour of rain, you're at a decided disadvantage compared to the Camry that just whizzed by you, like it or not.