There are numerous threads dealing with the handling of the 04 vs earlier models, and some discussion of changes to spring rates, sway bars, etc. I have never seen an in-depth discussion how the front to back tread width plays a role.

Pre 04 stock SO2s have a rear tread width of 8.5 and a front of 7.1 resulting in a rear/front ratio of 1.20.

04s stock RE50s have a rear tread width of 9.0 and a front of 6.7 resulting in a rear/front ratio of 1.34.

It seems like the relatively narrow tread width in front on the RE50s will contribute to understeer.

Other choices (using stock tire sizes) may dial out some of the understeer. SO3s 9.0/8.0 ratio of 1.12. SP9000 8.8/7.9 ratio of 1.11. Eagle F1 7.8/7.1 ratio of 1.10.

There are other tires that do not list tread width, but I think that when trying to modify the understeer/ oversteer properties of this car the tread width may be as important as suspension mods.

Has anyone with a MY 04 put on wider stock size fronts? If so, what were the results?

 

you can also fiddle with the tire pressure to tune the handlin

 

I like the extra research, but quite honestly it depends more on your opinion on understeer/oversteer bias of the stock car. If you don't have an opinion then you're not driving hard enough for it to matter. If you do have an opinion then you already know what to do (higher ratio = more understeer, lower ratio = more oversteer).

Get around the tread width ratio desired, it's not going to be all important. Changing air pressure and alignment have just as much effect on static oversteer/understeer as minor treadwidth ratio changes. Just get a reasonable ratio to do what you want. It is more important to get a good tire compound/tread pattern for your application than to rule out tires on width specs.

 

I'm not ruling anything out at this point, but would like to hear from anyone who has mounted a wider than stock (tread width) front tire on a MY04+.

Anyone?

 

IMO the car understeers a little more than I would like. The initial turn-in is slow to the point of being annoying. I've tried alignment and am running UK specs at this point.

The reason I started this thread is because I just put on some all season tires for witer (on stock 16 inch wheels) 7.42 tread width fronts and 8.32 in the rear.

The balance of the car is more to my liking than with the stock RE050's.

I would like opinions from other people on replacement tires for the stock 04 wheels. I can't afford to buy multiple sets of tires to experiment.

 

FO2K, how's UK spec fix understeer for you? Came from MY03, the understeer is quite annoying!

I'm about to switch from RE050 to Piralli PNero Zero M+S in couple of days for the winter. I also looking to get new alignment done as well, I think I can't wait to do it the same time I lower the car anymore, the understeer is bugging the h*ll out of me!

I try to play around with air pressure today, 32PSI in the front, 35PSI at the back. After drove through some twisty back roads, I can deffinitely tell you that this is can only be temporary solution! While the car turns more naturally with slightly hint of understeer( not to mention a sloppy slow steering wheel rates..), the back feel too harsh and jittery over bumps, can't call that a good balance either.

I think the best way to go is the whole suspension system revise(back to pre04), plus new alignment. Sad but true, ...still have to deal with slow poke steering wheel ... If you like, I can PM you the result after install the tires on Monday, let me know, I like to gather as much info as possible without having to try every tires and suspensions on the market as well.

Cheers

 

Let me know how the new tires work for you. What size are you getting?

 

215/45/17 and 245/40/17, look like the front has a good inch over RE050, there's no spec for tread width list on tirerack web site, only section width which are F8.5/R9.6 VS F8.3/R9.7 stock. Only thing I'm worry about is the front going to feel even havier, but then slow steering ratio is a major pain in the the @$$ and wallet to fix, ..I don't even dream about it.

I'll let you know.

 

BTW, the UK spec alignment seems to keep the rrear planted. Fronts are wearing flat across. I have a little inside wear on the rears. I may decrease the camber a bit.

With the wider front tread you are getting I think you will notice quite a bit less understeer.