banflu

Hi again everyone

I've been reading tire threads for the past two weeks
But I still need to clarify some things.

As some might remember, I've been having an understeer problem for a loooong time. Since I bought my car 8 months ago actually.
It also has had an excessive oversteer problem, but I'm not complaining there

But after a very hairy experience of understeer, lift off - CRAAZY oversteer, mega sideways in a not-so-wide road at over 120km/hr, I decided .. I need to replace my tires asap. I'm just lucky nothing's happened to far.

Anyway, the car is currently on Toyo Proxes T1-R. And, although I generally had a good idea of them, they seem to age really quickly. Mine are 4 years old with some thread left and they really do not grip at all .. so I will get something else now.

I am torn between Goodyear Eagle F1 Asymmetric (I like goodyears) in 225/45/17 - 245/40/17
or OEM RE050-MZ in the factory sizes.

What is the recommended setup?
The Bridgestones are only slightly more expensive .. they are basically the same price so that is not an issue.

The reason for the 225 size on the F1s is that I -REALLY- hate understeer. So I prefer a slightly wider tire up front, if that helps at all.
I would get 255/40 in the rear if that were possible, but goodyear dont make this size in the f1 asymmetric, so i would have to go for 245/40.

I read similar threads about this, but I think they were from the past when the MZs were really expensive .. and that is not the case anymore.

Soo which is the best tire? (as in GRIP, wet and dry)
Dont really care about tire wear .. I use it only on the weekends so that is not really an issue.

ZDan

In a well-balanced car, you can easily get under- or over-steer depending on DRIVER INPUTS. That's the whole idea. With correct driving technique you should get enough oversteer on braking to facilitate rotation into a corner, then it's up to you to carve an efficient arc from turn-in to apex to track-out, taking into account that the car's understeer/oversteer behavior is HIGHLY dependent on what you're telling it to do. Generally, lifting off the gas/getting on the brakes induces oversteer, and getting on the gas induces understeer. This is NORMAL.

The AP1 S2000 is *ESPECIALLY* prone to lift-throttle oversteer, which you have discovered. When you lift, not only do you get "natural" oversteer from loading the front tires and unloading the rears, the AP1 gives you a healthy dose of additional oversteer as the outside rear toes relatively outward. Stupid gimmicky rear geometry gives rear toe-in with bump, which has *always* been a bad idea (surprised they didn't take a lesson from the FC RX-7 and the original NSX).

I don't know what tires are available to you in Malta, but go to the Tire Rack's website (clickie on banner above) to get test data on most performance tires and customer survey results on a whole slew of tires.

FWIW, the OEM RE050 tires aren't rated highly (27th out of 32 Max Performance Tires).

If you drive in the rain, pick from the "Max Performance" category.

If you don't drive in the rain and/or you want maximum dry performance and are willing to sacrifice some hydroplaning resistance, pick from the "Extreme Performance" category.

And don't go with 225/45-17 fronts and 245/40-17 rears, it looks, erm, not so good...
Bigger diameter fronts with more pooch gives a definite, noticeable "big fronts/little rears" look.

go with 215/45-17 and 245/40-17
or
215/45-17 and 255/40-17
or
225/45-17 and 255/40-17


I'd go with Dunlop Sport Maxx TT or Continental ExtremeContact DW over either of the tires you're considering, btw...

But NO tire will prevent you from experiencing what you experienced! Lifting off the throttle in the AP1 when you start to feel the back end get loose is a recipe for disaster. You gotta modulate it through the oversteer. Big lift => big spin!

banflu

hi ZDan,
Thanks, I really appreciate your detailed, informative post.

I just saw Tirerack's ranked list of max performance tires.
I do drive it in the rain sometimes, so best avoid the extreme performance tires.

In Malta there isn't really a wide range of tires to choose from. And what is available is usually very expensive.
One of the best local tire agents with good prices is Toyo Tires; they always have plenty of stock in any size, but as I said before I really dont want to go with Toyo once again.
I think that they don't like too many heat cycles. Or maybe this is true for any tire - I dont know, but I want to experiment.

I will be buying my tires from the UK. Prices are much cheaper, and I have already made arrangements for shipping them to Malta for a very good price.

Unfortunately, most tires available in the US are not available in the European market. A good case in point is the Dunlop Star spec.
Extremecontact dw, pilot sport ps2 zp, sportmaxx gt - not available.
eagle f1 gs-d3 is discontinued.

So I guess the f1 asymmetric is the best choice left. As you said, it fares much better than the RE050.

What you said about the 225 makes sense I guess. I will go with 215/45 and 245/40.


Your comments about the handling characteristics were very interesting.
Yes I have become quite familiar with the lift-off oversteer. At first it started to surprise me.. but now I have gotten very much used to it, and have started to use it to my advantage. The car is actually helping you to turn into the corner. It gives you incredible turn-in. The only problem is when you actually need to stop quickly while cornering. What happens then?? This is something I always wondered.

Overall I'm quite happy with my car's handling characteristics..its just that there is really not enough grip. Although I would like less understeer, the fact is that the oversteer that is currently present is, in actual fact, dangerous. So, with new tires I will hopefully keep the current 'balance', but it will just take longer to reach the car's limits.
I am currently "enjoying" these understeer/lift off/oversteer characteristics at just 40 km/hr in roundabouts ... which is fun! but it becomes dangerous at higher speeds in normal roads.
This is a sports car, it should handle certain speeds in certain corners. Right now, it doesnt.

BUT on the bright side .. I have learnt these characteristics at relatively low speeds in normal conditions .. so it will now make it safer to practice them at higher speeds on good rubber.


Regarding this crazy bump-steer, is there something we can do to fix it?
Do the rear bump-steer kits actually solve the problem? Those tie-rod looking things? And how are they different to the OEM items?