SwappedNA

iTrader: (1)

After getting back into Auto-X from a very long break, I was looking at a set of tires, as they are coming due for replacement.

Sticking with the stock wheels, I'm debating on if its worth going up to 245/45's or staying with the stock sized 225/50's.

I don't want to stretch too large of a tire onto the stock wheels, can anyone comment on if the tradeoff of a larger width tire is worth it in an auto x setting? The car is a daily as well (just putting that out there to be thorough).

GoodfellaFD3S

iTrader: (213)

Back in the day it was looked at as a popular 'upgrade' because of the added contact patch while still keeping stock OD. Basically 10mm more overhang on each side of your 8 inch wide wheel...... IMO it comes down to what you gain in traction vs what you lose in control and steering feel in transitions etc. The Yokohama Advan A052 are available in both sizes, I recommend going to Tire Rack to compare specs. Looks like 0.7 inches wider and 0.4 inches smaller in OD, different load ratings (the 225mm is XL so rated to take more curb weight). Interesting that they spec an 8 inch wheel as the 'measured rim width' or recommendation for the 245mm. I can tell you that I run this tire on my 18 inch Fikse wheels and they are STICKY. Behave more like a 100 TW Toyo R888R on the street in my experience. Some Tire Rack data below that didn't copy/paste all that well:

225/50R16
96W XL
7/32" Starting Tread Depth
200 A A
1,565 lbs50 psi
7/32"21 lbs
6-8"7"9.1"7.9"25"
831JP

245/45R16
94W SL
7/32" Starting Tread Depth
200 A A
1,477 lbs51 psi
7/32"21 lbs
7.5-9"8"9.8"8.4"24.6"
845JP

j9fd3s

iTrader: (3)

Step one would be to look in the rule book, usually you have a tire size limit.
if you were road racing the tire wants a little stretch so 225 on an 8" wheel is good, but 225 on a 9" wheel is better. 245 would work autocrossing, so this post is a little pointless, but look in the rules

SwappedNA

iTrader: (1)

I was looking at tire rack earlier, and I will likely go with the Advan A052, the Azenis RT660's, or I might drop to a higher treadwear and get the Continental Extremecontact sport's, they have a 340TW I believe.

I really want the Advan's or the Azeni RT660's, but the issue I'm worried about is, since I daily the car, I don't want to run into an issue with wet roads, thus I'm considering the Continental's.

I did look into the rule book, and I can't really find much that specifies what I am allowed and not allowed to do given that I am in A Street Prepared (I can't remember what pushed me into it off the top of my head, but I believe it was the Power FC). I suppose my biggest concern is making my turning sluggish running such a wider tire on the factory rim.

Curious as to if I should just get a qood quality factory sized tire that I mentioned above, rather than trying to go 20mm oversized, or maybe meeting in the middle with a 235, but again, only if it doesn't drastically effect the handling. I suppose that is my biggest qualm at the moment.

scotty305

iTrader: (2)

I've run both stock size and 245/45R16 on stock wheels, but it wasn't anything like a back to back test. I replaced old sets of tires with new sets of tires (and different brands and sometimes different treadwear ratings) a few times since 2004 so the newer ones felt better than the worn ones. I'm not a good enough driver to say if one had better response or feel than the other. I think the tire compound or construction is going to make more of a difference than 20mm width.

Grassroots Motorsports has a nice-looking tire article that they have been updating, I especially like the chart near the bottom. https://grassrootsmotorsports.com/ar...-buyers-guide/

GoodfellaFD3S

iTrader: (213)

^Scotty, thanks for posting that link up

Swapped NA, how many miles a year do you drive and what kind of power are you making?

If it was me I'd probably look hard at the Azenis RT615k+ as it seems to be the longest lasting and rain friendly while still offering solid grip.

Funny enough, I run that tire on my little 1991 honda prelude in a 14 inch (!) size and can confirm it's a very streetable tire

SwappedNA

iTrader: (1)

The car is my daily, but I don't have a long commute whatsoever. It may get driven a few times a week, Figure as an extreme, 10,000 miles a year, but I feel its much less than that. Power is likely only slightly above stock, PowerFC on a basemap if I had to guess with a Racing Beat catback and resonated midpipe.


What makes you pick the RT615k+ over the RT660's?