Do 315s Fit in the Back?

[jfritz27]

Originally Posted by thefilipaneseboy

Wow I totally forgot to update the thread. 0 issues with fitment in the rears and the front

Thanks

Now trying to confirm whether the 295 would fit up front with the B16 kit (with either a 5 or 10 mm spacer), a mild drop, and around -3 of camber... anyone know?

[calubi]

Originally Posted by thefilipaneseboy

Wow I totally forgot to update the thread. 0 issues with fitment in the rears and the front

How much camber are you running?

[thefilipaneseboy]

Originally Posted by jfritz27

Thanks

Now trying to confirm whether the 295 would fit up front with the B16 kit (with either a 5 or 10 mm spacer), a mild drop, and around -3 of camber... anyone know?

I have a friend running that in the front with about -3.8 I believe. If I remember correctly, he's running a 10mm spacer in the front too

[thefilipaneseboy]

Originally Posted by calubi

How much camber are you running?

-2.2 in the rears

[JustAnothaM4]

My setup:

BBS E88 w/ Nankang AR-1
18x10.5 295/30
18x11.5 315/30
Camber: -3.3 F -2.2 R

[jfritz27]

Originally Posted by JustAnothaM4

My setup:

BBS E88 w/ Nankang AR-1
18x10.5 295/30
18x11.5 315/30
Camber: -3.3 F -2.2 R

Nice, thanks.... what suspension are you running? Spacers?

[JustAnothaM4]

Originally Posted by jfritz27

Nice, thanks.... what suspension are you running? Spacers?

I'm still on the stock KW 3W suspension and no spacers at all.

[silverbackf8x]

I’m presently running a 275/35/18 & 315/30/18 Nankang CR1 setup on my F80 with MCS coil-overs. No issues with rubbing.

Plan to run a Titan-7 Forged Wheels square setup of 18x10.5” +34 offset, front with 15mm spacer, with 295/30/18 Nankang AR1, & Toyo RR.

Going to compare a square to a staggered set of AR1 & RR, staggered setup of 295/30/18 & 315/30/18 Nankang AR1 with the present 18x11 Rear & 18x10.5 +34 front using a 15mm spacer.

I know of a M4 using factory style/type springs running, 18x10 front +20 offset and a 5-10mm spacer to clear the spring up front with a 295/30/18 and 18x11 +44 offset rear with 315/30/18

[terron]

Originally Posted by thefilipaneseboy

Wow I totally forgot to update the thread. 0 issues with fitment in the rears and the front

Sorry for reviving this old thread but, do you remember if you had to roll your fenders or change the camber to get the 315’s to fit on the rear of your car? I’m getting a set of 18x11 ARC-8’s and want to fit 315’s if possible. Note that my suspension is completely stock.

[thefilipaneseboy]

Originally Posted by terron

Sorry for reviving this old thread but, do you remember if you had to roll your fenders or change the camber to get the 315’s to fit on the rear of your car? I’m getting a set of 18x11 ARC-8’s and want to fit 315’s if possible. Note that my suspension is completely stock.

Nope. Zero fender work was done

[terron]

Originally Posted by thefilipaneseboy

Nope. Zero fender work was done

Awesome, thanks a mil.

[b_w.]

Originally Posted by terron

Awesome, thanks a mil.

Works great with a 36 to 44 offset wheel. Will want some negative camber to tuck it under the fender.

[Dareem_7777]

Originally Posted by silverbackf8x

I’m presently running a 275/35/18 & 315/30/18 Nankang CR1 setup on my F80 with MCS coil-overs. No issues with rubbing.

Plan to run a Titan-7 Forged Wheels square setup of 18x10.5” +34 offset, front with 15mm spacer, with 295/30/18 Nankang AR1, & Toyo RR.

Going to compare a square to a staggered set of AR1 & RR, staggered setup of 295/30/18 & 315/30/18 Nankang AR1 with the present 18x11 Rear & 18x10.5 +34 front using a 15mm spacer.

I know of a M4 using factory style/type springs running, 18x10 front +20 offset and a 5-10mm spacer to clear the spring up front with a 295/30/18 and 18x11 +44 offset rear with 315/30/18

So you prefer square or staggered ???

[terron]

Originally Posted by b_w.

Works great with a 36 to 44 offset wheel. Will want some negative camber to tuck it under the fender.

This was the other half of my concern. On a ‘44 offset wheel, will I need to add negative camber that’s outside the range of the standard hardware? ie will I need to purchase aftermarket camber arms?

[M3SQRD]

Originally Posted by terron

This was the other half of my concern. On a ‘44 offset wheel, will I need to add negative camber that’s outside the range of the standard hardware? ie will I need to purchase aftermarket camber arms?

An 11et44 will allow a 315 to be fitted to the rear without rubbing on a f82, not sure about a f80. However, an 11et44 even with a 25 mm spacer won’t work on the front unless you add BW GTmore front suspension arms and their custom MCS front strut with a lug monoball-clevis mount (upper eye mount) and BW custom offset camber plate. Also, a 315 is too wide for an 11” wide wheel. You should be using an 11.5” wide wheel with proper support for a 315.

[terron]

Originally Posted by M3SQRD

An 11et44 will allow a 315 to be fitted to the rear without rubbing on a f82, not sure about a f80. However, an 11et44 even with a 25 mm spacer won’t work on the front unless you add BW GTmore front suspension arms and their custom MCS front strut with a lug monoball-clevis mount (upper eye mount) and BW custom offset camber plate. Also, a 315 is too wide for an 11” wide wheel. You should be using an 11.5” wide wheel with proper support for a 315.

That’s the other part I’m surprised by. Both Apex and Bimmerworld suggest a 11” wheel for a 315 tire. Which conflicts with pretty much every other recommendation I’ve found. I’m still going to run the 11” wheel with 315 Continental ECF tires (just like the GT More) but that’s mostly because there aren’t many 18x305 options.

[M3SQRD]

Originally Posted by terron

That’s the other part I’m surprised by. Both Apex and Bimmerworld suggest a 11” wheel for a 315 tire. Which conflicts with pretty much every other recommendation I’ve found. I’m still going to run the 11” wheel with 315 Continental ECF tires (just like the GT More) but that’s mostly because there aren’t many 18x305 options.

They run an 11” front wheel with a 31 mm spacer which makes the wheel offset of -1. An offset of -1 means more than half the wheel is sticking out of the wheel well (frontspacing). They also clearly state that this fitment requires a 30 mm spacer, special suspension parts, including the front strut and camber plate, to fit the GTmore. It will not fit on a stick f8x. Additionally, the f8x M2 CSR 18et46 wheel which is 10.5et46 needs a 41 mm spacer to work on the GTmore. The widest you can run with a 295 is a 10.5et36 with a 15 mm spacer and anything with a more aggressive offset and increased front neg camber won’t tuck an 11et30 with even a 10 mm spacer won’t fit because it’ll hit a MCS 2/3/4WR damper with a 2.25”-dia, 5”-long spring . I could not find where they recommend using a 11” wide wheel on a stock car. Show me where BW says an 11” wheel fits a standard f8x?

[terron]

Originally Posted by M3SQRD

They run an 11” front wheel with a 31 mm spacer which makes the wheel offset of -1. An offset of -1 means more than half the wheel is sticking out of the wheel well (frontspacing). They also clearly state that this fitment requires a 30 mm spacer, special suspension parts, including the front strut and camber plate, to fit the GTmore. It will not fit on a stick f8x. Additionally, the f8x M2 CSR 18et46 wheel which is 10.5et46 needs a 41 mm spacer to work on the GTmore. The widest you can run with a 295 is a 10.5et36 with a 15 mm spacer and anything with a more aggressive offset and increased front neg camber won’t tuck an 11et30 with even a 10 mm spacer won’t fit because it’ll hit a MCS 2/3/4WR damper with a 2.25”-dia, 5”-long spring . I could not find where they recommend using a 11” wide wheel on a stock car. Show me where BW says an 11” wheel fits a standard f8x?

My point wasn’t about offsets. I was speaking about putting a 315 tire on an 11” wheel. Both Apex and Bimmerworld recommend 315’s on an 11” wheels, rather than an 11.5” wheel.

[M3SQRD]

Originally Posted by terron

My point wasn’t about offsets. I was speaking about putting a 315 tire on an 11” wheel. Both Apex and Bimmerworld recommend 315’s on an 11” wheels, rather than an 11.5” wheel.

The point about a 10.5et21 with a 295 is it barely fits without rubbing the front strut assembly. An 11et-1 will not clear a MCS strut with a 2.25”-dia, 5”-long main spring. You need to run the complete GT4/GTmore front suspension arms, upper-eye mount strut and offset camber plates to run a 305 or 315 front tire. Show me a link to where BW states a front 315 can fit on an 11et-1 wheel in a stock front suspension geometry and strut orientation/angle?

A 315 is too wide for an 11” rim. 305 is the widest if you want to extract all of its performance. The widest tire on a 10.5” is 295 and a 10” is 285 so 11” is 305. Wider tires on a narrow rim increase lap time, not reduce it. Check out this GRM tire-wheel test (plenty more articles and YouTube videos proving the same thing):
https://grassrootsmotorsports.com/ar...always-better/

[terron]

Closing the loop on this thread, I went with ARC-8's 18x10" ET25 in the front and 18x11" ET44 in the rear. And I managed to fit a 275/35 front and 315/30 rear without the need for any camber adjustments. Tires were Continental ECF.

Everything fit great, no rubbing, and I went to my first track day at Atlanta Motorsports Park yesterday and had no issues. Well, no tire related issues.