Koru_Kinshi

So, I've got a friend who is selling the tires off of his stock Supra rims. They have about 150 miles on them, and are as follows in size:

235/40/17
255/40/17

Will these work on our car for better handling? I know the fronts are 45 and the backs are 40. Will it cause a problem if they're both 40, or do you think this will be a good set up? Also, will a fender roll be necessary? Since it's only 10 wider, I'm hoping we'll be good w/no roll.

EURO KNG

What kind of tires are they lol.

Koru_Kinshi

Falkens. Not sure the name of the tires. Finding out tomorrow.

hooleyboy

I think its best to stick with OEM side walls on stock wheels. Also Have you ever ran a 255 tire in the rear. Lots of us run 255/265 wide tires with no problems. The only reason I say this is a 255 tire will weigh more than a 245 in the worst possible place to have added weight. Outside of the wheel. Power losses may be small but when i put my first 255 tire on my stock AMG wheel i could just feel the car being a bit sluggish. Then I made the mistake of adding heavy wheels too. Dyno results after heavy wheels and heavier tires I was down 20whp! Just something to think about.

splinter

+1 hooleyboy.

Recently upgraded to 245/40s and 255/40s on a destaggered 8.5” setup.



According to the tire manufacturer’s data, their individual weight is within 2 lbs. of our original equipment sizes. Be that as it may, the additional unsprung mass is noticeable – nothing that a set of Renntech or BBS wheels couldn’t properly address – but there were none to be found under the Christmas tree this year. Adhesion at the limit has increased and understeer has been markedly reduced. Its improved balance is worth the inevitable weight increase, IMHO. Can’t speak to the performance characteristics of Falkens – as I’ve not driven on them – but if their price is right there’s likely no harm in giving ‘em a go.

It’s advisable to have your tire installation shop ensure that there is sufficient strut-to-tire clearance upon installation - as they could be close - depending on the tires’ actual size and contour:

Calspeed

They will fit. It isnt the ideal setup and Falkens are not the best tires. But if the price is right... if you are running with stock suspension... If you are not overly concerned with the minimal weight gain... go ahead and use them.

Based on your information, the new tires will actually have a smaller circumference. A distance of almost 2 inches on both the fronts and rears. So you may give up a little in weight but with the shorter tires you may make it up in acceleration. But you will also be reving the motor higher at freeway speeds. And if it applys, your maximun top speed may suffer. I dont think that the tires will be much heavier.

As for a wider wheel. It should be slightly wider. Very slightly! But since your rims are not changing you will probably not see much of a difference in its stance when viewing from the rear of the car. Sorry...

It is a give and get situation. In my opinion more "give". You will be giving up some RPMS. Have a larger top of tire to fender gap. Possible weight gain.

I wouldnt do it.

Miguel

Koru_Kinshi

Well, what about for handling purposes? I'm not strictly concerned about the car being only a freeway battler? I figured wider tires would help for handling purposes.

Oh, found out they are the stock height. 45 in front and 40 in back. Also, I only have the stock AMG rims. Not looking to change my rims or anything.

Calspeed

New tires always handle better then older tires. But overall if the playing filed is even you would not feel a difference in handling.

10mm is so slight especially if using the stock rims. And anyone with these questions usually doesnt have the experience to take the cars to an absolute limit to notice a difference in handling. Certainly no insult to anyone. I think tire knowledge and performance driving experience go hand in hand.

Cheers and Happy New Years Eve!

Miguel

Koru_Kinshi

....Riiight.

When I had my C230, I increased the size of the tires by 20, and it made quite a difference. More rubber is more rubber, irregardless. I'll admit, I'm not a track runner. It's more for casual driving in the canyon, but still I can feel the difference whether 10 wider or 20 wider...7 years of experience will do that.

I asked the question to see simply if they would fit without roll. I know wider tires will increase grip. It's the height that I was more concerned about, but now that I know they're the same height, I'm not concerned anymore.