[Crazyotter]

I have a set of PS4S 315/30 from my old C8 that I want to put on the G87

I was told in another thread that they should fit but wanted to confirm that before taking them to get put on

[M_Power Rob]

Originally Posted by Crazyotter

I have a set of PS4S 315/30 from my old C8 that I want to put on the G87

I was told in another thread that they should fit but wanted to confirm that before taking them to get put on

I wouldn't on stock rims.

[Crazyotter]

Originally Posted by M_Power Rob

I wouldn't on stock rims.

They are technically within the range for this size wheel.

Would you be concerned with rubbing or something else?

[M_Power Rob]

Originally Posted by Crazyotter

They are technically within the range for this size wheel.

Would you be concerned with rubbing or something else?

Yeah, I know it is in the extreme range but you can run into issues with handling, tire wear, sidewall rollover and potentially failure. Can't comment on contact issue with suspension. These issues can be exacerbated depending on what tire it is.

I am running 305/30/20 on a 20x11 rim.

[Crazyotter]

Originally Posted by M_Power Rob

Yeah, I know it is in the extreme range but you can run into issues with habling, tire wear, sidewall rollover and potentially failure. Can't comment on contact issue with suspension. These issues can be exacerbated depending on what tire it is.

I am running 305/30/20 on a 20x11 rim.

Do the 305s feel significantly better than the stock size?

[M_Power Rob]

Originally Posted by Crazyotter

Do the 305s feel significantly better than the stock size?

TBH, didn't put any miles on the stock tires. Car was taken by enclosed trailer from the dealership to shop where rims went on and 305s. I have gone through two sets of drag radials and now running Cup 2s. I need every bit of ture I can get as I am tuned to 740whp (I would be running 315s but it would be too close to rubbing under certain conditions).

[Crazyotter]

740whp?
Holy shit! Gotta love these engines

[DutchBoysRacing]

The car is significantly more planted with the 305. Our cars need as much rubber under them as possible to combat the weight. I recently did tire testing on 265/35/18 MAXIS 200tw and it was hilarious. A ton of fun, but definitely not as fast as a 295/305

I wouldn't do 315's on anything smaller than a 11 inch. Over sized rubber as Rob brought up can have issues.

I think grass roots motorsport did an article on multiple sizes on multiple wheel set ups (275/285/295 on a 10/10.5/11). These aren't the actual sizes but basically it turned out that a slight stretch performed "better".

[Crazyotter]

Originally Posted by DutchBoysRacing

The car is significantly more planted with the 305. Our cars need as much rubber under them as possible to combat the weight. I recently did tire testing on 265/35/18 MAXIS 200tw and it was hilarious. A ton of fun, but definitely not as fast as a 295/305

I wouldn't do 315's on anything smaller than a 11 inch. Over sized rubber as Rob brought up can have issues.

I think grass roots motorsport did an article on multiple sizes on multiple wheel set ups (275/285/295 on a 10/10.5/11). These aren't the actual sizes but basically it turned out that a slight stretch performed "better".

Thanks for the response!
I knew the 315s probably wouldn’t work but I was just hoping someone would say that they would since I already have them sitting in my garage

[Crazyotter]

So I’ve come to grips (no pun) that the 315s won’t fit, but I still want to upgrade so I’m going to get new wheels (20x11 rear) and put 305s on them.
My suspension is stock.
Will 305s fit perfectly or will I need spacers?

[M_Power Rob]

Originally Posted by Crazyotter

So I’ve come to grips (no pun) that the 315s won’t fit, but I still want to upgrade so I’m going to get new wheels (20x11 rear) and put 305s on them.
My suspension is stock.
Will 305s fit perfectly or will I need spacers?

305s on 20x11 rims with the right offset will be fine (no spacers). I am running them and lowered on Ohlins Road and Track coilovers. With my setup 315s will not fit.

With the right offset in 20x11 rims, and depending on ride height, you should be able to go with the 315s (others have done it).

This may be a stupid caveat but I am talking rears only

[Crazyotter]

Oh really?? So on a 20x11 wheel on stock suspension, I can use the 315s ?

[M_Power Rob]

Originally Posted by Crazyotter

Oh really?? So on a 20x11 wheel on stock suspension, I can use the 315s ?

With the right rim and offset, yes. Who were you planning on getting rims from?

[Crazyotter]

Originally Posted by M_Power Rob

With the right rim and offset, yes. Who were you planning on getting rims from?

I was thinking about these so far

https://www.forgelitewheels.com/product/fl1

https://www.vtforged.com/store/p84/R...-WHEELS.html#/

[M_Power Rob]

Originally Posted by Crazyotter

I was thinking about these so far

https://www.forgelitewheels.com/product/fl1

https://www.vtforged.com/store/p84/R...-WHEELS.html#/

I am not familiar with Forgelite.

For the VT, reach out to AndyVTForged to discuss offset and fitment for the 315s.

[Crazyotter]

Originally Posted by M_Power Rob

I am not familiar with Forgelite.

For the VT, reach out to AndyVTForged to discuss offset and fitment for the 315s.

Just messaged him, thanks again for your help.

[Crazyotter]

Originally Posted by M_Power Rob

I am not familiar with Forgelite.

For the VT, reach out to AndyVTForged to discuss offset and fitment for the 315s.

He said it would be a tight fit and might rub with the 315s so I’m just going to do the 305s
My plan is
20x10 front with 285/35
21x11 rear with 305x30

Look good?

[M_Power Rob]

Originally Posted by Crazyotter

He said it would be a tight fit and might rub with the 315s so I’m just going to do the 305s
My plan is
20x10 front with 285/35
21x11 rear with 305x30

Look good?

With those sizes you will most likely need to modifo the fender liners in the fronts.

I have 20x11 with 305/30/20 on rears and 20x9.5 with 275/30/20 on fronts.

[Crazyotter]

Rather not modify anything so will 275s be ok up front?

[M_Power Rob]

Originally Posted by Crazyotter

Rather not modify anything so will 275s be ok up front?

Depends on exact rim and tire specs. The liner mod is minor, its just replacing the plastic venting with an aluminum screen.

[ScottyRyan2019]

Originally Posted by Crazyotter

He said it would be a tight fit and might rub with the 315s so I’m just going to do the 305s
My plan is
20x10 front with 285/35
21x11 rear with 305x30

Look good?

The 285/35/20 fronts will be approx 27.9" tall.

The 305/30/20 rears would be approx 27.2" tall.

I don't think the fronts would look good at all.

[Crazyotter]

Originally Posted by ScottyRyan2019

The 285/35/20 fronts will be approx 27.9" tall.

The 305/30/20 rears would be approx 27.2" tall.

I don't think the fronts would look good at all.

Sorry I meant to put 285/30 but I’m just going to do 275/30 so no fender mods are needed