Help GY Eagle F1 GSD3 floaty handling
 

On my 03 WRX the factory fit Bridgestones had gone at the front - wanting the best wet performance i have replaced them with Eagle F1 GSD3's and stuck them on the rear so the Bridgestones are now on the front. The handling of the car is strangely affected - the back end now seems to float on fast sweepers and braking. The chassis feels less precise than before. I know the bridgestones are run flat so have very stiff sidewalls, I can only assume the F1's are causing this due to the softer side walls, the car suspension is std, tyre pressures are 32 f/ 35 r, it feels like i need to add the prodrive springs to compensate! Anyone else experienced this? I chose the F1 following favourable comments here and in mag reviews - would like the aparrent precision of the bridgestones with the wet performance of the F1 any ideas?

Its because they're not bedded/scrubbed in yet, I had the same to, watch out for lift off oversteer with new eagles :) After about only 50miles they are much better now. Drop the rears by a couple of psi to.

Also mixing the 2 different types of compound will not help at all. Replace those Bridgestones with Eagles soonest, otherwise u might be visiting a hedge.

agreed - never mix tyres on these cars - just not worth it mate.

Get the GSD3 all round, scrub them in, then you'll be happy.

regards

Mikey

Well know trait never mix different brands of tyres as you have found out they don't like it.
Still at least you have not binned it and found out the hard way.

Regards

John

Thanks - didnt want to throw away the bridgestones as being on the rear they have worn evenly and have good life left, also want to monitor wear as the old fronts wiped out the edges, seems to be a common prob, may get laser alignment done b4 fitting the next 2 gsd3. Does anyone rate the std bridgestones?

Those tyre pressures look well out... try 33 front 31 rear as it says in the manual...

Jza

Talkin of scrubbing in. I recently changed my wheels and ended up with
Pirelli P-Zero Rosso's 18". The first 2-3 week they were awful, had no confidence in the car waht so ever. Now though after bout 200 miles they are superb, bags of grip :D :D . The only thing got do now is track day
it as there are little nibble/bobbles right on the very outside edge, which I just can't seem to get rid of with road use, even when very aggressive

bear in mind you have gone from little or no tread (no flexibility) to loads of tread (loads of flex) hence the sensation. it has little to do with mixing tyres. just edited to say that I would not advocate mixing tyres, its just unlikely that this is causing said problem.

stick with it, although it feels dangerous at first the feeling will wear off. or you'll crash;)

One, never mix different types of tyre on a performance car; two, new tyres are always fairly lethal when brand new, particularly in the wet, they need to be scrubbed in; three, new tyres with loads of tread will always feel more squirmy than your old 'slicks', because of the relatively deep tread moving around; and four, if you take the car to track day on new tyres you will almost certainly destroy them in a few laps on a dry circuit, the deep tread will not like it at all, the tread blocks will finish up scalloped ( all raised up at the corners ) How do I know ? I almost did it to a set of new Toyos ! Oh and your rear pressures look way too high.

Can only confirm not to mix tyres.
Did that once years ago on my old golf vr6 and it was not a good idea at all. The car's handling was totally transformed, it became unpredictable if not to say insidious. At times, real bad and sudden oversteer occured which was very uncommon before.
I very soon replaced the whole set of tyres and everything was fine again.

Regards,
Pat

Thanks for the replies and advice, just read em all as not been able to get on sn seems to have been down for a couple of days, im just trying to scrub out the front Bridgestones and try the GSD3 all round!
I dont know if the bridgestone Re 050 are the run flat versions, according to their web site this tyre is available as std or run flat, my tyres certainly dont have RFD anywhere on them so my stiff sidewall theory may be cr*p.

I'm in the process of changing now - just put 2 Goodyears on the front (but got them with 1K mileage on already so worn in nicely), but I'm still running Toyo's on the rear in my SpecC.

I've not noticed any difference in handling in the last 500 miles and although I'll be changing soon (perhaps all 4 as I only got the Goodyears to see me until I could get a set of SO2's, but may just get 2 more Goodyears dependant on how hard the mrs shouts at me for thinking of all 4).

Those tyre pressures won't be helping. I find that the F1's do move around a lot, they're very communicative which is why I like them, the problem is you're getting loads of feedback from the rear and not so much from the front which makes the rear seem loose.

Personally I'd try putting the F1's on the front which may help it feel more stable, or at least more predictable.

I too have a similar problem. I replaced the standard Bridgestones with GSD3's all round and had the tracking set at the same time. I now am getting bags of understeer as I try to power out of corners. It does feel as though the tyre walls are flexing. I have tryed changing the tyre pressures to 35 front and 31 back. I have done about 200 miles since fitting them.

You'll need another 300 at least for them to bed in properly - they'll be lethal till then (almost had a grassy incident when I first ran Toyo's in and tried an "enthusiastic" cornering technique having only done 100 miles on them) :D

Reckon it took well over 1K miles before mine felt ok. Think it's because of the 1 ply sidewalls.

I'm running 36f 32r on the 215x70x14. 36f sorted the front out quite early on in tyre life but changing preesures in rear didn't have large affect till the tyres got some miles on them.

Stick with them and you'll be well pleased.

Cheers

Mark

Just an update to this old thread, now put the GSD3 on the front so have the set of 4 and the car is now sorted so you were all right about not mixing the tyres, I will never do it again!
The GSD3 is softer and turn in is slightly worse but the balance and precision has been restored.