I am running 2016 Porsche GT4 and looking for a tire I can daily drive and drive on the track. I only drive ~2K miles per year on the street and do 6-8 DE's per year at Sebring. Sebring International is about 90 miles away and it rains a lot and heavy in Florida. I like the reviews on both of these tires but I am a little worried about hydro planning when driving on the street. (I don't drive on the track when wet).
Would you expect either the Kumho or the Bridgestone to significantly better than the other on in terms of avoiding hydro planning?
dps214
SuperDork
9/24/23 7:31 p.m.
Bridgestone much better than kumho but still not great in the grand scheme of things. The kumhos have less void area to begin with and then turn to essentially slicks once the top layer of tread wears off.
Edit: I assume you have some 19" wheels? Because neither of those tires are available in oem GT4 sizes.
V730s are absolutely the worst I've ever driven in the rain both on track and on the street. The above video is when brand new BTW.
You can feel the whole car hop puddles from 55mph+. I've driven the car into the office without switching to my ECS and it sucks.
RE71RS can't possibly be worse.
Just looking at the treads I would expect the V730 to be highly susceptible to hydroplaning, the tread is very shallow, non-directional, and doesn't reach far across the tire.
You might also want to consider Continental ECFs, I've found these to be excellent for a track & autocross car with occasional street use, I've only had them start to hydroplane in hurricane-force rain.
flatlander937 said:
V730s are absolutely the worst I've ever driven in the rain both on track and on the street. The above video is when brand new BTW.
You can feel the whole car hop puddles from 55mph+. I've driven the car into the office without switching to my ECS and it sucks.
RE71RS can't possibly be worse.
Wow that is awful. I thank you for posting this video because I was considering these tires in the future.
I'd imagine any TW200 tire is going to be optimized for dry conditions with wet traction being "tolerable when brand new" at best. At least this has been my experience with the few I've driven on.
the stones are gonna be better in the rain
I currently have both of these tires. The Bridgestones are gonna be much better in the rain. They do pretty well autocrossing in the rain too. If you are willing to consider some A052's, they are phenomenal in the rain.
I run RE71s on my M3 on the street and track. Never had any concerns with wet road handling.
I think the RE71rs is the tire of choice for autocross in the rain. It might have been Tire Rack that showed them faster in the wet than even the AO52.
I don't know that I've ever seen anyone cross shop these two tires. The V730 is a decent autocross tire, but the RE71rs is fantastic.
I'm not sure what size wheel you're running on a GT4, however, the Yokohama AO-52 is a great tire for the wet. I run them on my autocross/time trial CRX, and was amazed by the wet weather performance. Granted, any 200 TW tire will not do amazing in the wet, especially if there are puddles but the AO-52 does it the best out of any "hot" 200 TW tire these days IMO. The issue with them is very poor wear on camber challenged cars, and they do "fall off" after around 1 hot lap on track.
Just so everyone has it, our Ultimate track tire guide does rate tires based on wet-weather performance.
dmc996
New Reader
9/25/23 2:45 p.m.
Just drive down on your street tires and have a friend bring your full racing slicks on another set of wheels and then you can swap them out on the track. Better yet: borrow a tire trailer, put a hitch on your GT4T and drag it down to the track to change out. Problem solved!
I've got the RE-71RS on my E30 M3 and have been very impressed by the wet grip. Then again, my tires are pretty narrow: 225/50/15 on 15x8" wheels. Probably helps with cutting through water.
My experience with 200TW tires is that they're fine in the wet and absolutely suck in any standing water, especially when they're worn. I was driving through a thunderstorm on the freeway with half worn RT660s a while back and the bit of standing water in the tire grooves was enough to keep the stability control on all the time. The car felt like it was on water skis. This isn't a one time thing - it's happened on a variety of "autocross tire of the year" tires.
They're also pretty much entirely useless on snow and ice.
A052 and RE71RS are fine ideas for lower speed (aka autocross) and less water, but are out of their depth for high speed in significant water.
My latest recommendation for such conditions, while not giving up too much in the dry is the new Bridgestone Potenza Race. Only comes in bigger sizes, but is amazing in the wet, and only a half-second off the top 200tw stuff in the dry. Plus, it's got amazing street manners (not noisy).
Deets ==> https://grassrootsmotorsports.com/articles/can-the-bridgestone-potenza-race-really-do-it-all/
jwagner (Forum Supporter) said:
They're also pretty much entirely useless on snow and ice.
Most (if not all) 200TW tires are not recommended for use below 40°. I don't even leave my car outside if it is getting colder than that.
With that said, I drove from Houston in Kansas City in January with freezing rain on a set of Federal 595RS-RR's and I didn't die. Pretty slick though, lol.
