Tire fitment issues in the rear

[*Axel]

Originally Posted by Yoshoobaroo

The stock tires are Primacy HP, not Primacy MXM4. There’s a big difference, the HPs are much better.

OK, that's all good, but I'm mainly asking about size. Can I get 245s on a 7.5x17" wheel?

[*Axel]

Originally Posted by *Axel

OK, that's all good, but I'm mainly asking about size. Can I get 245s on a 7.5x17" wheel?

At Tire rack, this is search results for "ALL TIRES FOR 245/45R17"

I would like to not have to change wheels to get some wider tires.

Someone please tell me what is the widest tire i can get on a 17x7.5" wheel! I think it should work, but I may have to insist to get a tire place to mount them.

[timurrrr]

Originally Posted by *Axel

I would like to not have to change wheels to get some wider tires.

Someone please tell me what is the widest tire i can get on a 17x7.5" wheel! I think it should work, but I may have to insist to get a tire place to mount them.

Why though? Why is 225/40R17 not enough for you?

If you insist on putting the widest tire possibly, each tire manufacturer specifies the "acceptable" range of tire widths on their website. LMGTFY what Michelin says about Primacy HP in 245/40R17:

[PNW Shaggy]

57CR 17x9 +38 w/ 245/40 Pilot Sport 4S tires. Stock suspension & alignment
Parked at the crest of a small hill to load the suspension up some.

Second photo is after ~150 miles of fast paced backroad driving. No rubbing anywhere, even over rough road conditions. Thinking something more like a +42~45 would be better though. Not sure how well this aggressive of poke will handle HPDE's.

[timurrrr]

Originally Posted by PNW Shaggy

17x9 +38 w/ 245/40 Pilot Sport 4S tires.

Thanks for the data point! Michelins typically run narrower, so these 245/40's might be comparable to 235/42-ish size of something like RT660 or A052.

[PNW Shaggy]

Originally Posted by timurrrr

Thanks for the data point! Michelins typically run narrower, so these 245/40's might be comparable to 235/42-ish size of something like RT660 or A052.

Definitely. I don't think a RT660 or similar wider tread 245 will fit without a bunch more camber in the rear on a +38. I don't really think +38 is going to be a great track offset.

[Scubadriver]

How is the clearance on the inside? Would ET42 or ET45 square work?

[Frost]

Originally Posted by PNW Shaggy

57CR 17x9 +38 w/ 245/40 Pilot Sport 4S tires. Stock suspension, stock alignment
Parked at the crest of a small hill to load the suspension up some.

Second photo is after ~150 miles of fast paced backroad driving. No rubbing anywhere, even over rough road conditions. Thinking something more like a +42~45 would be better though. Not sure how well this aggressive of poke will handle HPDE's.

Dumb question but can you please do me a favour and see on your stock suspension and stock alignment if you comply with this rule?

"The widest point of the tire, above the axle, does not protrude more than
13mm (0.5”) from the widest point of the OE wheel well opening when
measured in a vertical plane coincident with the axle line."

In other words, if you put a ruler straight up perpendicular to your axle line on the wheel hub, does that line exceed the fender by anywhere near 13mm or 1/2"? Do you know roughly how much it's at?

Many thanks.

[PNW Shaggy]

Originally Posted by Frost

Dumb question but can you please do me a favor* and see on your stock suspension and stock alignment if you comply with this rule?...

Apologies for such poor photo work, didn't have a camera & tripod on hand. Is this what you were looking for?

TL;DR No, ~15mm from the furthest point at the top of the tire/wheel. More if you measure from the bottom due to camber.

They do not comply with the rule you posted. Using a straight edge with a level against the farthest out point above the hub, I measured roughly 15mm. If the rule only cares about the furthest point period, then that'd be the lower half of the wheel due to camber (obviously) so add a few mm.
Straight edge is 2mm thick. Calipers were placed against the outside face of the straight edge and, using the depth gauge, leveled the straight edge vertically. The very poor setup reads 17.78mm. When not trying to fenagle this image solo, a more perfectly leveled straight edge read 17.49mm. Minus 2mm for the thickness of the straight edge and you get a perfectly backyard mechanic measured 15.49mm. Yes, this is far from perfect, but it was the quickest way I could get this info without digging out more equipment.

P.S. The bolding in your comment read a little condescending. Not saying that was the intent, just wanted to throw that out there.

[Frost]

Originally Posted by PNW Shaggy

Apologies for such poor photo work, didn't have a camera & tripod on hand. Is this what you were looking for?

TL;DR No, ~15mm from the furthest point at the top of the tire/wheel. More if you measure from the bottom due to camber.

They do not comply with the rule you posted. Using a straight edge with a level against the farthest out point above the hub, I measured roughly 15mm. If the rule only cares about the furthest point period, then that'd be the lower half of the wheel due to camber (obviously) so add a few mm.
Straight edge is 2mm thick. Calipers were placed against the outside face of the straight edge and, using the depth gauge, leveled the straight edge vertically. The very poor setup reads 17.78mm. When not trying to fenagle this image solo, a more perfectly leveled straight edge read 17.49mm. Minus 2mm for the thickness of the straight edge and you get a perfectly backyard mechanic measured 15.49mm. Yes, this is far from perfect, but it was the quickest way I could get this info without digging out more equipment.

P.S. The bolding in your comment read a little condescending. Not saying that was the intent, just wanted to throw that out there.

Apologies for the bolding but I've been reading WAAAAY too many people who keep lowering the car and slapping on wide sticky tires.

But MANY THANKS for that measurement my dude! Much appreciated! It's a rule book from the time attack series I participate in and you just saved my ass from penalties!

[jongers]

Some pictures I found on my phone from the past couple of weeks.

Stock suspension/camber for 18x9.5 +40 w/ 255 35 Adven Apex 601.

Been a bit too busy to get my RLCA + coilovers installed, but hoping to get it aligned to ~-2.5 to -3 in the rear with around -3 in the front with a 1-1.5 inch drop.

[timurrrr]

From Facebook, 17x9.0 et35 wrapped in 245/40 RT660 with "camber probably between -2.5 and -3.0":



Same car and tire with et43:

[Varelco]

Originally Posted by jongers

Some pictures I found on my phone from the past couple of weeks.

Stock suspension/camber for 18x9.5 +40 w/ 255 35 Adven Apex 601.

Been a bit too busy to get my RLCA + coilovers installed, but hoping to get it aligned to ~-2.5 to -3 in the rear with around -3 in the front with a 1-1.5 inch drop.

How much inner clearance do you have from the stock struts?

[jongers]

Originally Posted by Varelco

How much inner clearance do you have from the stock struts?

A few mm.