[Mk2] [Turbo] Wide Tyres and lowering the car.

[Rahzel]

Hi guys.

I currently have a set of 17" alloys on with what i would concider wide tyres for the mr2.

The tyres are 255/40 on the rear and the wheel has an offset of 35 and is 9" wide and 235/40 on the front with an offset of 32 and is 8" wide. The front tyres are very close to the strut casing and the top perch of the strut. Would a 225/40 give me a bit more room?

Also when lowering the car it doesn't lower the perch of the strut just above the wheel? I'm looking to fit my eibach pro lines and i know they don't drop the car that much from stock rev 1 ride height.

Anyone got any experience running these size of tyres?

Cheers

[-:[KM]:-]

Would a 225/40 give me a bit more room?

It will give 4mm more clearance. Dropping to a 215/40 17 will give you 8mm more clearance than the 235/40.

Also when lowering the car it doesn't lower the perch of the strut just above the wheel?

Nope, you lose a little damper stroke instead.

[Marf]

Also when lowering the car it doesn't lower the perch of the strut just above the wheel?

Nope, the gap between the perch and the wheel will not change, its only the distance between the perch and top mount that changes.

Also, with a 255/40/17 on a 9j ET35 you will get arch rubbing. I have that exact size on the rear of my car, and without the arches rolled I couldnt go over a speed bump at 5mph without the arches fouling the tyre.

I rolled the arches on the rear which has pretty much cured the problem, also a little negative camber helps.

[Rahzel]

Marf, are you running lowering springs or stock ride hight?

Do you think i will get away with running the eibachs? The rears look to sit in the arch and are not flush like the front. I'd like to push the rear out a bit more.

[Marf]

Stock ride height





I think with the eibachs on your current setup you'd get rubbing on the front, possibly the rear too. You'd def get rubbing if you added a spacer at the rear looking at your pics

Are your rear wheels definitely ET35? Mine are ET35 and they look more flush than your rears

[Rahzel]

Yes mate, the rears are deffinatley et35. Maybe because the fronts are et 32 with 235's that it makes it looke like the rears are sitting in more.

I'm sure about the et's as they are the exact same ets as the 16's i got of the same wheels.

[Marf]

Maybe because the fronts are et 32 with 235's that it makes it looke like the rears are sitting in more.

Yeah you may be right there.

[bobhatton]

How far can the arch to rolled to fit wider tyres?



Bob

[Leon.]

Would a 225/40 give me a bit more room?

It will give 4mm more clearance. Dropping to a 215/40 17 will give you 8mm more clearance than the 235/40.

Well it's 4mm in height, and 5mm in width.

Also when lowering the car it doesn't lower the perch of the strut just above the wheel?

Nope, you lose a little damper stroke instead.

Well strictly speaking, unless you maintain the exact same rolling radius then you will get a slight change in height between perch and wheel.



Rahzel, unless you have exactly the same negative camber front and rear, they will look like they're spaced differently as your eye reads the wheel against the arch. It looks like your rears have more negative camber than the fronts, so coupled with the extra 3mm offset, will give you a different appearance.

2 options:
1. 3mm spacers on the back to eliminate the offset difference and set up both with the same camber.
2. Give a little more negative camber to the fronts / a little less to the rears to get them appearing the same/similar, albeit at slightly different angles.

[-:[KM]:-]

Also when lowering the car it doesn't lower the perch of the strut just above the wheel?

Nope, you lose a little damper stroke instead.

Well strictly speaking, unless you maintain the exact same rolling radius then you will get a slight change in height between perch and wheel.

Those calculations WERE taking into account the differences in radius and therefore height Leon.


Just to add, I've 255/40*17 on the rear with an ET41 and they fit perfectly with standard struts. Shame I've had to remove the coilovers though!
The ride is a dream now, but too soft.... and too high!