My stock Potenza's are getting worn out so it's time to replace them with something else I can use for Autoxing. It's pretty clear from the large number of threads here that the tires of choice are the Kumho and Hoosier R-compounds. Unfortunately, at this point in time (and budget) I have to get something that I can drive to and from events, potentially a couple hundred miles at a time.

I'm looking for some 18" tires that are streetable. They need to be stickier than the stock Potenza's. I don't really care if they have a low wear rating as I will NOT be driving them daily - only for AutoX.

I was planning on putting the same size all around to help reduce the understeer and to have the advantage of rotating them.

Should I just shop by brand and look into other Kumho's such as the V700's? (based on the assumption that all Kumho's will be good). I've also seen some positive posts about the Falken Azenis.

Any suggestions are appreciated.

 

Falken Rt-615's.

 

Falken RT-615. How wide are your rims? Get some 275+ and you will be set

 

Dave, if you're not going with an R-compound then go with the Falken Azenis RT-615. 255/40 would be nice all around.

 

Just be aware that if you have TDC or VDC, you need to stagger the diameters, or you'll drive the computer nuts (and subsequently to the dealer to have it's memory flushed).

 

I just turn my TCS off whenever I get in the car.

 

These will be on 8" wide rims. No stagger won't be a problem as I'll only be doing AutoX and I'll turn VDC off.

Thanks guys. It looks like Falken's will be the ticket.

Should I try to get the lowest profile possible to reduce the wheels diameter (rotational inertia) and get stiffer sidewalls?

 

If they make a 275/35/18 that would be great.

 

Are you certain about this? I checked with Steve (Knight White99) who has run same size tires on his Z with VDC on and off, on track and off, and he assured me that it didn't cause any problems. I just ordered my RT-615's.

 

there's a certain percentage of diameter difference there has to be before making any problems IIRC.

 

Not to mention that if you change the front diameter and rear diameter in a similar fasion, it won't make as much difference....

 

I have the Falken RT-615's and they are pretty good. I have 245/40/18 Front and 255/40/18 Rear on track edition wheels. They are a good tire if you want to use it for auto-x but don't want to have to change to race tires before and after an event. Please do not think that these tires will even be close to an R-compound as they are not. They are not a comfortable tire to drive on the street. I currently use mine everyday until I can get my beater back from my girlfriend , and I hate the way they pull in every direction on the road. They also make me feel every single bump in the road and on the bigger ones it is very pronounced. Don't get me wrong they are perfectly fine on flat smooth pavement, but on the crappy roads here in Cincy they outright suck.

In conclusion, they are a great tire for what it sounds like you are looking for. Just be realistic in what you want from the tire and don't get pissed when those guys with R-compunds consistently beat you by about 2 seconds. If you are really serious about autocrossing then you might want to bite the bullet and get some race rubber. I don't know about you, but I hate it when I get beaten.

Vince

 

Vince,

I pretty much accepted the fact that I'll still be behind the R-compound cars by a few seconds, but fortunately for me, nobody else in the area is running R-compound tires right now.

My goal was to buy some Kumho's but I have the dilemma of how to get to the event and carry 4 wheels. From what I can tell, you can do it but it involves 1) filling the car with wheels and 2) not closing the rear hatch. For overnight/out-of-town trips that wasn't going to make it, especially in case of rain. The alternative is a trailer or rear end tire rack of some sort and that's just more $$$$ - maybe next year.

I'm hoping between wider, grippier tires all around and a front sway bar that will help my times improve a second or so.

 

I know what you mean, we all have to make sacrafices to feed our racing bug. I do know that you can fit 4 wheels and tires in the car and be able to close the hatch. You can fit one in the trunk under the Strut Brace, one between the strut brace and the seats, and 2 standing straight up in the passenger seat. I know it is not optimal by any means but it does work, and I've done it several times. Man, you must be lucky to not have other people running R-compunds in your area cause around here if you dont have em then you loose. I think that the Falken RT-615's would be a great tire for you and your purposes. Good luck with racing!

BTW, I love the pics of you autocrossing in the rain. Simply awesome!

Vince

 

Damn that's cool! I'd love to see a picture of this. Don't get me wrong I totally believe you but I never thought it would work which is why I end up driving to the track on my track tires.

Oh and I'm using the RT615s as well for track lapping duty as I do ocassionally drive on them for extended periods on the street. Definitely the best non-R cmopund tire I used on the track thus far.

 

theres another way to do it too!
follow the above with a tire in the spare wheel well. Also, the tire btw the seats and strut bar. But with wider tires 2 wont fit in thr front so youd be sol. Instead, put one tire in the passenger seat and slide it as far forward as possible. Then put a tire behind the seat and btw the cubby box. Lean seat back to secure that tire. You now have for tires in your car.

gl!

for your sidewall, isnt it larger sidewall better? or is that for drag racing.

Another critical point is tire pressures, change them throughout the day and check them. At my last race my fronts creeped up 5psi and rears 3psi. My car was understeering like a queen. Needless to say when i drop the psi it got better. I only wish i had seen it sooner (we got nine runs, i didnt check until the after my 6th)

 

I had read on many occasions that people have been able to stand up a wheel behind the seats in front of the strut bar, but I don't see how you can close the hatch.

It's only about 20" from the trunk to the top of the hatch and the wheels are about 26" tall.

I would love to see somebody do a thread on how to fit 4 tires in the Z.

I'm curious about those of you who carry them in the front seat, do you use some type of restraint to keep them from bouncing around. I would hate to get in an accident - if you know what I mean.

 

You don't stand the tire up between the strut brace and the seats, you lay it horizontially between the 2 humps for the speakers and the strut brace and the hatch will close.

I put the seatbelt through the 2 wheels standing straight up in the passenger seat, then I try to put some towels or sheets over areas where the tires or wheels may damage the car. Kind of a pain in the butt to do, but it does work for those of us who do not or can not have a trailer on the Z.

Vince

 

It's been done a few times that I can remember. Here is the only one I can find in about 5 seconds as I am about to leave work. I know I have seen threads before with pics as well.

Vince

https://my350z.com/forum/showthread....g+extra+wheels

 

Gee, it seems like the phrase "interior damage" is pretty common.

Looks like next's years budget has to include a trailer and R-compound tires.