Please recommend wider tires for 20" 666M

[AMOR]

Hi, i'm looking to upgrade my stock PSS tires to get better traction. I need better traction for launch mainly (rear wheels), handling grip is fine as it is from stock. I'm keeping the stock 20" 666M wheels, as I like them a lot. I've been researching the forums, and based on what i've read there are several options to go with. Car is a 6MT ZCP F80.

Please recommend which would be the best solution:
1. Keep OEM tire size (265/30 r20 front; 285/30 r20 rear), upgrade all tires to stickier Michelin PS4S or PSC2's.
2. Put wider tires for front and rear (275/30 r20 front; 295/30 r20 rear).
3. Put wider tires for rear only, keep front stock (265/30 r20 front; 295/30 r20 rear).

So far i'm leaning towards the third option. In theory, car should preserve stock sharp handling by keeping OEM size for the front and get better traction by upgrading the rear's. Will loose some corner handling in the rear's though and possible aquaplaning issues? Please let me if someone tried any of these 3 setups, any advise is appreciated.

[ElysianFields]

Last I checked, I don't think they make Cup 2s in the stock size for all four corners.

[AMOR]

Originally Posted by ElysianFields

Last I checked, I don't think they make Cup 2s in the stock size for all four corners.

You’re right, I didn’t notice that, was just looking at Cup 2’s in the 295/30 r20 size. So I guess 1st option narrows it down to only P4S. That’s probably not much advantage over PSS in stock sizing.

[ElysianFields]

Originally Posted by AMOR

You’re right, I didn’t notice that, was just looking at Cup 2’s in the 295/30 r20 size. So I guess 1st option narrows it down to only P4S. That’s probably not much advantage over PSS in stock sizing.

I think you're right. From what I have heard, PS4S is only an advantage in wet conditions and offers a bit less road noise.

[MPoweRo]

You can run a PSC2 N0 or N1 spec 245/35 on the front and the tread width is the same.

[MN2///M]

AMOR welcome to the forum.

There is tons of info in the forum on this for your reading pleasure, but the consensus is for street driving that the Pilot Sport 4s in the stock 265/30/20 for the front and 295/30/20 for the rear.

The P4s is about .5" wider than the stock star spec Pilot Super Sport for the front and about 1.1 inches per spec than the stock star spec rear.

Definitely better grip from the P4s rear now than stock. Have not driven them in the rain yet, but according to reviews, this is where this tire is greatly improved over the PSS

I just replaced my rear tires, here are some comparison pictures:

[Robby29]

I’m on the same situation. Needing new tires. Subscribed

[Mikecom32]

Same here. I was leaning toward RE-71Rs for the rear in 295/30/20, but I'm open to options.

I've heard the 295 P4S is still wildly overwhelmed by a tuned S55.

[Continental02]

I run the 275/295 PS4s combination for my wet setup on my 666m wheels and cannot recommend the PS4s enough. It's an amazing tire in terms of wear and grip in the dry and wet. I am tuned with 565whp/570wtq and do not struggle for traction at all in the dry in second gear once warmed up. Even on a wet track, I could still go WOT in 3rd gear with this setup. I'm custom dyno tuned which probably makes a bit of a difference given the powerband is less aggressive, but it's a good bench mark to see what's possible. I would not recommend running the 275 up front as you will most likely rub on a stock car and it's just not worth the hassle in my opinion, but with the 265s you should be good to go. Prior to this, I had the 285 PSS and was very unhappy with it in comparison. For me, the difference between 285 PSS and 295 PS4 is night and day. Sure an argument could be made that 265/295 isn't ideal, but everything is about compromise and unless you're willing to spend money to modify other things, you're stuck with a decision. Do you want better rear traction or not? If so, get the 295 PS4. It's worth it.

Here's a video to show the tires in action for anyone that's interested. This is at Sonoma Raceway recently in the wet. With this setup I was 7 seconds faster than anyone else on track and was finding grip where others weren't, even comparing to a gentleman who was running the PSS's.

[AMOR]

Originally Posted by Continental02

I run the 275/295 PS4s combination for my wet setup on my 666m wheels and cannot recommend the PS4s enough. It's an amazing tire in terms of wear and grip in the dry and wet. I am tuned with 565whp/570wtq and do not struggle for traction at all in the dry in second gear once warmed up. Even on a wet track, I could still go WOT in 3rd gear with this setup. I'm custom dyno tuned which probably makes a bit of a difference given the powerband is less aggressive, but it's a good bench mark to see what's possible. I would not recommend running the 275 up front as you will most likely rub on a stock car and it's just not worth the hassle in my opinion, but with the 265s you should be good to go. Prior to this, I had the 285 PSS and was very unhappy with it in comparison. For me, the difference between 285 PSS and 295 PS4 is night and day. Sure an argument could be made that 265/295 isn't ideal, but everything is about compromise and unless you're willing to spend money to modify other things, you're stuck with a decision. Do you want better rear traction or not? If so, get the 295 PS4. It's worth it.

Here's a video to show the tires in action for anyone that's interested. This is at Sonoma Raceway recently in the wet. With this setup I was 7 seconds faster than anyone else on track and was finding grip where others weren't, even comparing to a gentleman who was running the PSS's.

Thanks for the feedback, very much appreciated. Just like you, i’m against upgrading front tires to a wider 275/30, even though some people on the forums are running such setup. I’m pretty happy with how the front behaves on stock 265/30 PSS tires. And the opposite situation for the rear, they struggle to handle even the stock power of the ZCP. By the way, I recently came across another interesting tire - Dunlop SP Sport Maxx Race. It’s a race compound tire developed for the porsche’s, they seem close to PC2’s but much better price. Worth trying?

Originally Posted by MN2///M

AMOR welcome to the forum.

There is tons of info in the forum on this for your reading pleasure, but the consensus is for street driving that the Pilot Sport 4s in the stock 265/30/20 for the front and 295/30/20 for the rear.

The P4s is about .5" wider than the stock star spec Pilot Super Sport for the front and about 1.1 inches per spec than the stock star spec rear.

Definitely better grip from the P4s rear now than stock. Have not driven them in the rain yet, but according to reviews, this is where this tire is greatly improved over the PSS

I just replaced my rear tires, here are some comparison pictures:
Attachment 1840709
Attachment 1840710
Attachment 1840711

You are right, lots of useful info here. Thanks for sharing, I didn’t know P4S is wider than PSS in stock size, good to know. What do you think about PC2’s for the rear only?

[moonluv810]

Would changing sizes impact on how the traction and stability control systems work?

[einscot]

looks like you have an f80. do NOT get 275s with the PS4S on the front. you will rub. take it from me, i learned a $600 mistake the hard way. for whatever reason, the f82s don't rub with the 275s up front, but our f80s will.

i'm trying my damndest to burn my front tires out so can go back to the stock size and not worry about if my tire is randomly going to explode on me on an on/off ramp curve.

the 295s in the rear are fine - i didn't notice a huge difference in ride quality from the OEM 285s, but that's probably because i'm too worried about my fronts to be honest.

[Robby29]

Originally Posted by AMOR

Thanks for the feedback, very much appreciated. Just like you, i’m against upgrading front tires to a wider 275/30, even though some people on the forums are running such setup. I’m pretty happy with how the front behaves on stock 265/30 PSS tires. And the opposite situation for the rear, they struggle to handle even the stock power of the ZCP. By the way, I recently came across another interesting tire - Dunlop SP Sport Maxx Race. It’s a race compound tire developed for the porsche’s, they seem close to PC2’s but much better price. Worth trying?



You are right, lots of useful info here. Thanks for sharing, I didn’t know P4S is wider than PSS in stock size, good to know. What do you think about PC2’s for the rear only?

I didn’t know this either! I’m definitely going to try PS4S in stock size. 265/285. Can I run spacers (12-15)to make this wheel flush or should I have smaller spacers (7.5-10) since it’s a bit wider than the PSS?

[Continental02]

Originally Posted by AMOR

Thanks for the feedback, very much appreciated. Just like you, i’m against upgrading front tires to a wider 275/30, even though some people on the forums are running such setup. I’m pretty happy with how the front behaves on stock 265/30 PSS tires. And the opposite situation for the rear, they struggle to handle even the stock power of the ZCP. By the way, I recently came across another interesting tire - Dunlop SP Sport Maxx Race. It’s a race compound tire developed for the porsche’s, they seem close to PC2’s but much better price. Worth trying?

I think it depends on what you're looking for. I think the PS4 is the best tire without compromising the stock ride quality and noise level. For me, I have two setups, one for street and then full slicks or semi slicks for the track. The PS4 performs in the dry close enough to my race setup grip wise that I couldn't see compromising ride or noise for just a little bit extra grip. I like to be comfortable when driving around on the street.

[Continental02]

Originally Posted by einscot

looks like you have an f80. do NOT get 275s with the PS4S on the front. you will rub. take it from me, i learned a $600 mistake the hard way. for whatever reason, the f82s don't rub with the 275s up front, but our f80s will.

i'm trying my damndest to burn my front tires out so can go back to the stock size and not worry about if my tire is randomly going to explode on me on an on/off ramp curve.

the 295s in the rear are fine - i didn't notice a huge difference in ride quality from the OEM 285s, but that's probably because i'm too worried about my fronts to be honest.

It rubs on my F82 also without any modifications. Seems like it's a your mileage my vary type situation. Not worth the risk in my opinion, not going to be a huge difference for street driving.

[Graves]

Good read. Gonna upgrade the front and rears when I get my car.

[BoxKing]

Originally Posted by einscot

looks like you have an f80. do NOT get 275s with the PS4S on the front. you will rub. take it from me, i learned a $600 mistake the hard way. for whatever reason, the f82s don't rub with the 275s up front, but our f80s will.

i'm trying my damndest to burn my front tires out so can go back to the stock size and not worry about if my tire is randomly going to explode on me on an on/off ramp curve.

the 295s in the rear are fine - i didn't notice a huge difference in ride quality from the OEM 285s, but that's probably because i'm too worried about my fronts to be honest.

This has not yet been proven, and the PS4-275/295 F8X "upgrade" have their isolated issues, and has yet to be determined why there are variances between 1 car to another; other than no 1 car is alike.

That being said, I took the plunge bc my tires are FREE, and I could give two shits if I had to bite the bullet and get new fronts. If this were not the case, I'd prolly get the PS4's in stock sizes or with stick fronts and 295 rears. Either way the PS4's in any arrangement would be a major upgrade.

[AMOR]

Originally Posted by BoxKing

This has not yet been proven, and the PS4-275/295 F8X "upgrade" have their isolated issues, and has yet to be determined why there are variances between 1 car to another; other than no 1 car is alike.

That being said, I took the plunge bc my tires are FREE, and I could give two shits if I had to bite the bullet and get new fronts. If this were not the case, I'd prolly get the PS4's in stock sizes or with stick fronts and 295 rears. Either way the PS4's in any arrangement would be a major upgrade.

What are the benefits of upgrading the fronts anyway? A little wider rear tires are for improved acceleration grip 100% of the time, but I assume upgrading the fronts would be useless for the street and maybe just some benefit for the track use?

[moonshine89]

I'm running 12mm/10mm spacers in the front/rear respectively on my stock 666m/super sport setup.

Will I be able to keep these spacers on if I upgrade to 265/295 4s?

[BoxKing]

Originally Posted by AMOR

What are the benefits of upgrading the fronts anyway? A little wider rear tires are for improved acceleration grip 100% of the time, but I assume upgrading the fronts would be useless for the street and maybe just some benefit for the track use?

Guess it all depends on whether or not your fronts are close to the end of their lifespan. The cost difference isn't all that much, and I'd rather not have a mixed set of two different performance tires on my car.

[Graves]

Originally Posted by BoxKing

Guess it all depends on whether or not your fronts are close to the end of their lifespan. The cost difference isn't all that much, and I'd rather not have a mixed set of two different performance tires on my car.

I'm anal like that as well. I don't like having mixed matched tires.

[AMOR]

Ok, so i’ve tried the 295/30 setup for the rear on stock 20’s, and that sucked. I didn’t get much better traction for launches, but lost the responsiveness of the rear wheels. Car feels unbalanced with front being swift and responsive and the rear is unwilling to follow. Now I got a set of Apex EC-7 18x11 wheels and MT SS drag radials in 305/35/18 size and will try them out soon at the strip. For daily driving and track days I highly recommend keeping OEM 265/285 sizing for 666M wheels, as was originally designed by BMW, otherwise you will loose in handling.