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[AP3X_FTW]

Looking forward to seeing these mounted.

[Adrian g.]

Originally Posted by AP3X_FTW

Looking forward to seeing these mounted.

Installed on the car

[AP3X_FTW]

Originally Posted by Adrian g.

Installed on the car

Very nice. Interested to see how you like the tires on track.

Did you end up running 12mm or 15mm spacers?

[Adrian g.]

Originally Posted by AP3X_FTW

Very nice. Interested to see how you like the tires on track.

Did you end up running 12mm or 15mm spacers?

15mm spacers on the rear.

[slicer]

Originally Posted by Adrian g.

15mm spacers on the rear.

I am curious. Why did you end up getting 295/30/18 instead of 295/35/18?

[Adrian g.]

Originally Posted by slicer

I am curious. Why did you end up getting 295/30/18 instead of 295/35/18?

1. Mainly due to the smaller overall diameter, thus making it much easier to fit without rubbing. The 295 runs wide (see attached pic) !

295/30/18 is 25.1
295/35/18 is 26.2

(front)
265/35/18 is 25.4

I never track with any form of TC so the slightly smaller rear tire isn't an issue for me.

Other benefits:
2. Smaller overall diameter will slightly help with gearing
3. Might help with front/rear weight bias since the rear will sit lower
4. 1.5lbs lighter per tire

[slicer]

Originally Posted by Adrian g.

1. Mainly due to the smaller overall diameter, thus making it much easier to fit without rubbing. The 295 runs wide (see attached pic) !

295/30/18 is 25.1
295/35/18 is 26.2

(front)
265/35/18 is 25.4

I never track with any form of TC so the slightly smaller rear tire isn't an issue for me.

Other benefits:
2. Smaller overall diameter will slightly help with gearing
3. Might help with front/rear weight bias since the rear will sit lower
4. 1.5lbs lighter per tire

Understood on the diameter helping with fitment but you have et44 wheels with plenty of options for making them fit. I have been running 295/30/18 Cup2's for the past few years with good results. The Cup2 is 1 lb lighter than the A052. However, I have been contemplating going to the A052 solely due to the fact that it's available in the taller 295/35/18 which is consistent with OE diameter. My understanding is that a taller tire will better manage heat (more volume) and keeping diameters consistent with OE will also help the ABS system. I too run without traction control and honestly have not detected any issue with ABS but it could be a subtle impact.

Lastly I think weight distribution impact may be the opposite of what you think. When corner balancing a car you actually increase the ride height on the corner that you want to increase the cross weight. However, that impact might not be transferable to tire size. I honestly don't know for sure - as tire diameter's influence on ride height and the spring perch's influence on ride height are two different things.

[Adrian g.]

Originally Posted by slicer

Understood on the diameter helping with fitment but you have et44 wheels with plenty of options for making them fit. I have been running 295/30/18 Cup2's for the past few years with good results. The Cup2 is 1 lb lighter than the A052. However, I have been contemplating going to the A052 solely due to the fact that it's available in the taller 295/35/18 which is consistent with OE diameter. My understanding is that a taller tire will better manage heat (more volume) and keeping diameters consistent with OE will also help the ABS system. I too run without traction control and honestly have not detected any issue with ABS but it could be a subtle impact.

Lastly I think weight distribution impact may be the opposite of what you think. When corner balancing a car you actually increase the ride height on the corner that you want to increase the cross weight. However, that impact might not be transferable to tire size. I honestly don't know for sure - as tire diameter's influence on ride height and the spring perch'e influence on ride height are two different things.

I have a few track days coming up, first one on 9/21. Since my last one, I installed a full BBK and moved to a staggered wheel/tire setup. I'm hoping these changes will be an improvement to the overall experience.

At this point, I'm more concerned with the A052 compound and how well it will work for me. As far as heat, according to my (perhaps not very accurate calculations using online volume cals) the rear 295’s should have ~20% more air volume than the fronts. That doesn’t take into account the distance to the friction point… I’m not an engineer, so I’m just thinking out loud here, but I will measure tire temps after my first session (without a cool down lap) via my infrared thermometer.

I recall reading that fitting a tire taller than 26" in the rear, in this width, can cause rubbing, which I do not want unless I have to deal with it. 295/30 will totally avoid that. And yes, I specifically purchased an et44 wheel so I can run a variety of spacers on the rear as needed.

As far as the balance of the car and how it is affected by running a smaller overall diameter in the rear, I'm inclined to think a bit more weight will shift to the rear (similar to getting on the throttle perhaps?) Again, something I will find out.

[slicer]

Originally Posted by Adrian g.

I have a few track days coming up, first one on 9/21. Since my last one, I installed a full BBK and moved to a staggered wheel/tire setup. I'm hoping these changes will be an improvement to the overall experience.

At this point, I'm more concerned with the A052 compound and how well it will work for me. As far as heat, according to my (perhaps not very accurate calculations using online volume cals) the rear 295’s should have ~20% more air volume than the fronts. That doesn’t take into account the distance to the friction point… I’m not an engineer, so I’m just thinking out loud here, but I will measure tire temps after my first session (without a cool down lap) via my infrared thermometer.

I recall reading that fitting a tire taller than 26" in the rear, in this width, can cause rubbing, which I do not want unless I have to deal with it. 295/30 will totally avoid that. And yes, I specifically purchased an et44 wheel so I can run a variety of spacers on the rear as needed.

As far as the balance of the car and how it is affected by running a smaller overall diameter in the rear, I'm inclined to think a bit more weight will shift to the rear (similar to getting on the throttle perhaps?) Again, something I will find out.

Gotcha. Let us know your findings.

FWIW - 295/35/18 is not at all difficult to fit with the right offset (I used to run G-Force Rivals in that size and many of my friends and customers run 295/35/18 Michelin PSS). It's the same diameter as 295/30/19 which is also commonly used on this platform.

It just so happens that a friend and I purchased a 295/35/18 Yokohama A052 tire to test fitment. See pics below for a comparison to 295/30/18 Michelin Cup2. It appears to be about 10mm wider than the Cup2 at it's widest point on the sidewall.

Untitled by slicerM, on Flickr

Untitled by slicerM, on Flickr

Untitled by slicerM, on Flickr

[Adrian g.]

Originally Posted by slicer

Gotcha. Let us know your findings.

FWIW - 295/35/18 is not at all difficult to fit with the right offset (I used to run G-Force Rivals in that size and many of my friends and customers run 295/35/18 Michelin PSS). It's the same diameter as 295/30/19 which is also commonly used on this platform.

It just so happens that a friend and I purchased a 295/35/18 Yokohama A052 tire to test fitment. See pics below for a comparison to 295/30/18 Michelin Cup2. It appears to be about 10mm wider than the Cup2 at it's widest point on the sidewall.

[img]https://farm2.staticflickr.com/1875/...93f6b5b5_b.jpg[/img]Untitled by slicerM, on Flickr

[img]https://farm2.staticflickr.com/1860/...80df69ae_b.jpg[/img]Untitled by slicerM, on Flickr

[img]https://farm2.staticflickr.com/1887/...0a2aa2b7_b.jpg[/img]Untitled by slicerM, on Flickr

That's good to know, the A052s do run wide. I always check the actual measurements on the manufactures site to get an idea of the actual size of a tire.

At this point, unless I experience an issue with the 295/30 heating up too much I'm likely to stay with this size, assuming the grip they provide is what I'm looking for (better then NT01)

If the staggered setup doesn't work out to my liking, I'll likely go to a 10.5 et27 square with a 285/35 tire and a larger front sway bar.

Are you going to use an 11" wheel to test fit the 295/35/18 A052? If so, I'm curious what size spacer will fit best, likely et32.

[slicer]

Originally Posted by Adrian g.

That's good to know, the A052s do run wide. I always check the actual measurements on the manufactures site to get an idea of the actual size of a tire.

At this point, unless I experience an issue with the 295/30 heating up too much I'm likely to stay with this size, assuming the grip they provide is what I'm looking for (better then NT01)

If the staggered setup doesn't work out to my liking, I'll likely go to a 10.5 et27 square with a 285/35 tire and a larger front sway bar.

Are you going to use an 11" wheel to test fit the 295/35/18 A052? If so, I'm curious what size spacer will fit best, likely et32.

Yes I will be testing with my 11 et28 wheel. It's going to be very tight but I think there's a chance it will fit.

I am not aware of any R-comp options in 285/35/18.

[slicer]

295/35/18 A052 Test Fit results = Fail

11 et28 wheel. -2 camber. Fender would not survive.

This tire needs at least 11" et31, if not higher offset.

A052 by slicerM, on Flickr

A052 by slicerM, on Flickr
A052 by slicerM, on Flickr
A052 by slicerM, on Flickr

[Adrian g.]

Originally Posted by slicer

295/35/18 A052 Test Fit results = Fail

11 et28 wheel. -2 camber. Fender would not survive.

This tire needs at least 11" et31, if not higher offset.

A052 by slicerM, on Flickr

A052 by slicerM, on Flickr
A052 by slicerM, on Flickr
A052 by slicerM, on Flickr

Perhaps a higher offset wheel and more camber would make it fit? But how well? No rub? Some rub?

These tires do run quite wide. So what's your next step with these?

[slicer]

Originally Posted by Adrian g.

Perhaps a higher offset wheel and more camber would make it fit? But how well? No rub? Some rub?

These tires do run quite wide. So what's your next step with these?

Per my previous post - this tire needs at least 11" et31 if not a higher offset.

The tire sits on the fender at the 10:00 position on the driver's side. Meaning it is making contact with the metal fender and will cause damage. More camber generally does not appreciably help correct a rub in that location (I have gone down this road before). I'm also not willing to compromise my alignment settings for this tire.

My next step is to go back to 295/30/18 Michelin Pilot Sport Cup2. I may consider another 295/30/18 tire in the future but I'm not planning to switch to 295/35/18. Partially because there's not a BBS E88 spec that I like in the et31+ range. In addition there are far more tire options in the 295/30/18 size. This is the one single 295/35/18 R-comp tire. Not worth switching everything up for the A052 IMO. Lastly, I will set my car up to run at or close to the same tire diameters front and rear. That will give me more options for running square or staggered. Adjusting to accommodate the taller 295/35/18 tire will require that i always run a taller rear tire (relative to the front) for maintaining my corner balance - pulling square tires/wheels out of the equation.

I purchased the A052 as an experiment to verify fitment (I only purchased one tire). I would have likely tried a set if it worked with my wheel spec. In addition I wanted this data to help direct customers on wheel and tire sizing. You will see in my post history I have tried a ton of different tires, wheels, offsets, etc. Every tire is different and no two tires are the same size despite their shared spec (as I you know). A 295 is not a 295 across all brands and performance levels. This is just one more data point to add to the others.

I hope this helps!

Below is a pic of the same wheel with a 295/30/18 Michelin Cup2 Tire (front spec is 10.5" with a 285/30/18 Cup2):

Untitled by slicerM, on Flickr

[Adrian g.]

Originally Posted by slicer

Per my previous post - this tire needs at least 11" et31 if not a higher offset.

The tire sits on the fender at the 10:00 position on the driver's side. Meaning it is making contact with the metal fender and will cause damage. More camber generally does not appreciably help correct a rub in that location (I have gone down this road before). I'm also not willing to compromise my alignment settings for this tire.

My next step is to go back to 295/30/18 Michelin Pilot Sport Cup2. I may consider another 295/30/18 tire in the future but I'm not planning to switch to 295/35/18. Partially because there's not a BBS E88 spec that I like in the et31+ range. In addition there are far more tire options in the 295/30/18 size. This is the one single 295/35/18 R-comp tire. Not worth switching everything up for the A052 IMO. Lastly, I will set my car up to run at or close to the same tire diameters front and rear. That will give me more options for running square or staggered. Adjusting to accommodate the taller 295/35/18 tire will require that i always run a taller rear tire (relative to the front) for maintaining my corner balance - pulling square tires/wheels out of the equation.

I purchased the A052 as an experiment to verify fitment (I only purchased one tire). I would have likely tried a set if it worked with my wheel spec. In addition I wanted this data to help direct customers on wheel and tire sizing. You will see in my post history I have tried a ton of different tires, wheels, offsets, etc. Every tire is different and no two tires are the same size despite their shared spec (as I you know). A 295 is not a 295 across all brands and performance levels. This is just one more data point to add to the others.

I hope this helps!

Below is a pic of the same wheel with a 295/30/18 Michelin Cup2 Tire (front spec is 10.5" with a 285/30/18 Cup2):

Untitled by slicerM, on Flickr

Looking at the pictures, you'd definitely need a few more mm to clear the fender. That tire looks like it would be perfect for a 11.5" wheel. I'm starting to think the optimal staggered wheel setup, for track, is 10.5f and 11.5r This is assuming a front setup without a helper spring and a reasonable ride height. And perhaps solid rear subframe bushings.


BTW, your car with those E88's

[slicer]

Originally Posted by Adrian g.

Looking at the pictures, you'd definitely need a few more mm to clear the fender. That tire looks like it would be perfect for a 11.5" wheel. I'm starting to think the optimal staggered wheel setup, for track, is 10.5f and 11.5r This is assuming a front setup without a helper spring and a reasonable ride height. And perhaps solid rear subframe bushings.


BTW, your car with those E88's

Thanks for the compliment!

I 100% agree that this tire looks like it needs an 11.5. It's so beefy. I did some looking and an 11.5" wheel might be possible but the offset would need to be perfect and for all of the reasons previously stated I'm sticking with 295/30/18.

I have a helper spring and fit 10.5 et15 with 285/30/18 ^ as seen in my pic.

[Richbot]

The 295/30 is the right call IMO, anything you can do to get the rear lower without crashing the tire into the body or the shocks into the bumpstops is worth the effort, tire diameter is a freebie on suspension geometry and travel, win. You aren't fighting to get the car low, it is low, because the tire isn't holding it as far off the ground. And low is fast, make no mistake about it, so long as you can keep the tire happy

The gearing and weight advantage is gravy.

It looks like running these square on a 10.5 would work too, just a little pinchy

This has turned into a really good "what fits and what doesn't and why" thread.

[slicer]

Originally Posted by Richbot

The 295/30 is the right call IMO, anything you can do to get the rear lower without crashing the tire into the body or the shocks into the bumpstops is worth the effort, tire diameter is a freebie on suspension geometry and travel, win. You aren't fighting to get the car low, it is low, because the tire isn't holding it as far off the ground. And low is fast, make no mistake about it, so long as you can keep the tire happy

The gearing and weight advantage is gravy.

It looks like running these square on a 10.5 would work too, just a little pinchy

This has turned into a really good "what fits and what doesn't and why" thread.

Good points that add to the reasons for choosing a 295/30/18 over the taller 295/35/18.

One more bonus is that the smaller diameter tire allows for a wider track width - whether it's done with a more aggressive offset and/or via adjustable suspension arms. The taller tire brings the 10:00 driver's side contact into play sooner. The smaller diameter is a much easier fit.

[Adrian g.]

Here are my thoughts from a recent track day with this wheel/tire combo.

1a. I much prefer the staggered setup and specifically more rubber on the back of the car. It helped in slower speed corners by simply providing more mechanical grip to the rear of the car. 1b. It also helped in fast speed corner by making the car easier to drive. What I mean by that is, with a square setup I needed to be very precise with the throttle as small inputs could upset the car. With more rubber in the rear, there was very little lift-off oversteer when I needed to adjust my throttle input.

2a. The compound worked well on the track. I was able to push for a full 30 min session without the tires getting greasy. 2b. These tires seem to wear a bit more like a street tire compared to the NT01. 2c. But, overall grip seemed a little bit better then the NT01 as my apex speeds were a little bit higher.

[Adrian g.]

Here is what the wear looks like after 3 x 30 min sessions running CCW. Any opinions on aliment or pressure changes are welcome


--------------
265/35/18 and 295/30/18 Yokohama Advan A052 on APEX EC-7 wheels, 10"f and 11'r.
GC plates at max camber and Eibach front sway at max stiff setting.

Tire pressures 29-30PSI cold measured the next day, and 36-37psi after a cool down lap.

--------------

Front LEFT

[Adrian g.]

Front RIGHT

[Adrian g.]

Rear LEFT