OEM Square Wheel and Tire Setup?

[Corsentino]

Hey guys,

I have a 17' GT350, currently stock, with no intention of serious mods. And I've been thinking about switching to a square setup in order to allow for wheel/tire rotation. My plan is to get a second set of stock rear wheels, (19x11) so that the fronts and rear sets can be interchanged.

I've done a bit of reading, enough to know that the offsets are different, and that this plan may be possible with some spacers, and that rubbing probably isn't an issue. But that's all I've come up with.

Has anybody written a thorough post about this idea before? Has anyone here done it?

I want to have a better understanding of what's going to be needed, and what are the steps.

Thanks for your input, and I look forward to hearing what you have to say.

Sponsored

 

[nastang87xx]

This might not work aesthetically. The problem is that the factory 19x11 rears are 62mm offset. Even with the 25mm spacer, you're going to have a lot of tuck. Apex Racing's EC7 is a 52 offset and works perfectly with a 25mm spacer. Effectively, the front offset on a 19x11 EC7 with a 25mm spacer is 27+ which is hairs (literally) off of factory spec.

The effective offset of a factory 19x11 would be 37+ and I think that's just too much.

 

[JAJ]

Hey guys,

I have a 17' GT350, currently stock, with no intention of serious mods. And I've been thinking about switching to a square setup in order to allow for wheel/tire rotation. My plan is to get a second set of stock rear wheels, (19x11) so that the fronts and rear sets can be interchanged.

I've done a bit of reading, enough to know that the offsets are different, and that this plan may be possible with some spacers, and that rubbing probably isn't an issue. But that's all I've come up with.

Has anybody written a thorough post about this idea before? Has anyone here done it?

I want to have a better understanding of what's going to be needed, and what are the steps.

Thanks for your input, and I look forward to hearing what you have to say.

It works perfectly - I've been doing it for two years now. Buy a set of OEM GT350R front hubs with the long studs, and a pair of 35mm Eibach spacers and you're good to go. You get 27mm front offset, the studs are more than long enough and 305's clear just fine. You'll need a set of open-end lug nuts if you want to run the regular rims - 2017 F150 open end lug nuts are a good fit.

BTW - the Eibach spacers come with studs in them - they're intended as a bolt-on adapter. Don't use them that way, just knock the studs out and once the studs are gone the spacers will slide over the long GT350R lugs on the car just fine.

 

[nastang87xx]

They make a 35mm spacer? Hory sheet...

 

[JAJ]

They make a 35mm spacer? Hory sheet...

Eibach S90-4-35-010-B

 

[Corsentino]

You'll need a set of open-end lug nuts if you want to run the regular rims - 2017 F150 open end lug nuts are a good fit.

Is there a way to do this while using the factory lug nuts?

 

[JAJ]

Is there a way to do this while using the factory lug nuts?

Once you've put the GT350R hubs on, the long "R" studs are too long for the closed end OEM lug nuts with regular GT350 10.5" front wheels. The OEM nuts will work with the 11" OEM rear wheels and the 35mm spacer. This is the same situation for any 11" rim that will fit both front and rear - the need for longer lugs and the spacer at the front makes it impossible to use the OEM nuts and OEM 10.5's together.

Now, if you're only doing a couple of track days a year, and you're inclined, you can swap front hubs in about a half-hour each. It's not much more work than changing the wheels. You could run the short-stud hubs for show and the long ones for go.

 

[Corsentino]

Once you've put the GT350R hubs on, the long "R" studs are too long for the closed end OEM lug nuts with regular GT350 10.5" front wheels. The OEM nuts will work with the 11" OEM rear wheels and the 35mm spacer. This is the same situation for any 11" rim that will fit both front and rear - the need for longer lugs and the spacer at the front makes it impossible to use the OEM nuts and OEM 10.5's together.

Now, if you're only doing a couple of track days a year, and you're inclined, you can swap front hubs in about a half-hour each. It's not much more work than changing the wheels. You could run the short-stud hubs for show and the long ones for go.

So let me see if i got this right:
the OEM front studs are the shortest, then the OEM rear studs are a bit longer, and the R studs (not sure front or rear) are the longest.
The R studs are too long to use the OEM lug nuts paired with the 19x11 wheel+spacer.
The OEM front studs are too short to use the OEM lug nuts paired with the 19x11 wheel+spacer.
The OEM rear studs are long enough to use the OEM lug nuts paired with the 19x11 wheel + spacer BUT they are not good for performance driving?

that's what i've interpreted from what you said. Let me know if i got any of that wrong. Also, what makes the last combination not good for performance driving?

Thanks for your time and input. I really want to make sure I get this right before I do anything.

 

[JAJ]

So let me see if i got this right:
the OEM front studs are the shortest, then the OEM rear studs are a bit longer, and the R studs (not sure front or rear) are the longest.
The R studs are too long to use the OEM lug nuts paired with the 19x11 wheel+spacer.
The OEM front studs are too short to use the OEM lug nuts paired with the 19x11 wheel+spacer.
The OEM rear studs are long enough to use the OEM lug nuts paired with the 19x11 wheel + spacer BUT they are not good for performance driving?

that's what i've interpreted from what you said. Let me know if i got any of that wrong. Also, what makes the last combination not good for performance driving?

Thanks for your time and input. I really want to make sure I get this right before I do anything.

I was only talking about the front axle - the rear axle doesn't need a spacer to work with the OEM 11" rear wheels. So responding to your questions in order:
1. Apparently I wasn't clear - the OEM GT350 (non-R) front studs are 6mm longer than the OEM GT350 (non-R) rear studs, which are the shortest. The OEM GT350R front studs are the longest - they're about 1-9/16" (40mm) longer than the regular front studs.
2. Apparently I wasn't clear here either - the R studs CAN take the OEM lug nuts if you combine an OEM rear 11" rim and a 35mm or 38mm spacer, but
- you can't use OEM lug nuts unless you also use a wheel that requires a 35mm spacer, and
- you can't use a 35mm spacer with the OEM 10.5" front wheel - it'll stick out too far - so, once you have the long lugs, you have to use open lug nuts with the 10.5's.
3. Correct - the OEM GT350 non-R front studs are way too short to use with an OEM rear 11" rim and 35mm spacer.
4. Not quite - the OEM rear studs, rims and nuts only work as they are provided by the factory - you can't run a spacer at the back without longer studs - but you don't need a spacer at the back, so it's all good.

Hopefully this clarifies it a bit.

 

[Corsentino]

I was only talking about the front axle - the rear axle doesn't need a spacer to work with the OEM 11" rear wheels. So responding to your questions in order:
1. Apparently I wasn't clear - the OEM GT350 (non-R) front studs are 6mm longer than the OEM GT350 (non-R) rear studs, which are the shortest. The OEM GT350R front studs are the longest - they're about 1-9/16" (40mm) longer than the regular front studs.
2. Apparently I wasn't clear here either - the R studs CAN take the OEM lug nuts if you combine an OEM rear 11" rim and a 35mm or 38mm spacer, but
- you can't use OEM lug nuts unless you also use a wheel that requires a 35mm spacer, and
- you can't use a 35mm spacer with the OEM 10.5" front wheel - it'll stick out too far - so, once you have the long lugs, you have to use open lug nuts with the 10.5's.
3. Correct - the OEM GT350 non-R front studs are way too short to use with an OEM rear 11" rim and 35mm spacer.
4. Not quite - the OEM rear studs, rims and nuts only work as they are provided by the factory - you can't run a spacer at the back without longer studs - but you don't need a spacer at the back, so it's all good.

Hopefully this clarifies it a bit.

OK.

So that means, what I should do is get 2 GT350R Front Hubs, with the long studs. and 2 35mm spacers. Take off the stock GT350 front hubs, replace with the GT350R Front Hubs. Add a 35mm spacer to each GT350R front hub. And now, a GT350 11" Rear Wheel should fit on any of the 4 corners of the car and hence they can be rotated, while the GT350R hub+spacer combo stays on the front.

That would imply 2 things:
1. the stud length of the OEM rear hub, and the stud length of the GT350R hub+spacer combo is the same or close enough.
2. the fitment is close enough to stock that the suspensions clears and the brakes clear

Also, would the fitment, be flush, or will I expect some poking?

Again, thanks for the help, and let me know if this is correct this time.

 

[JAJ]

OK.

So that means, what I should do is get 2 GT350R Front Hubs, with the long studs. and 2 35mm spacers. Take off the stock GT350 front hubs, replace with the GT350R Front Hubs. Add a 35mm spacer to each GT350R front hub. And now, a GT350 11" Rear Wheel should fit on any of the 4 corners of the car and hence they can be rotated, while the GT350R hub+spacer combo stays on the front.

That would imply 2 things:
1. the stud length of the OEM rear hub, and the stud length of the GT350R hub+spacer combo is the same or close enough.
2. the fitment is close enough to stock that the suspensions clears and the brakes clear

Also, would the fitment, be flush, or will I expect some poking?

Again, thanks for the help, and let me know if this is correct this time.

You've got it! As for fit and poke, the rear GT350 11" rim with a slightly thicker 38mm spacer is EXACTLY the same width and offset as an 11" OEM GT350R front wheel. With a 35mm spacer, the GT350 11" rear wheel/tire sits 1/8" (3mm) further into the wheel well, which is neither here nor there - the fit is really good.

 

[key01]

Once again, the 305/35-19 works on the 11" wheel upfront with no rubbing (35mm spacer)?
Sorry for jumping in here, but this square fitment with OEM wheels is an intriguing economical solution, all things considered.
thx!

 

[JAJ]

Once again, the 305/35-19 works on the 11" wheel upfront with no rubbing (35mm spacer)?
Sorry for jumping in here, but this square fitment with OEM wheels is an intriguing economical solution, all things considered.
thx!

Yes.

 

[Competition Orange]

Pics of the square rear wheel/tire on your car please?

 

[JAJ]

Pics of the square rear wheel/tire on your car please?

Sorry - it fit perfectly but was otherwise so unremarkable that I never took any pictures, and tires are heat cycled out now so they're not going back on. The car's on a different set of rims and tires now with stock 10.5's up front.

There's a funny story about this though - just to illustrate how good the fit actually is - I had a pair of 285/35's that I wanted to put on the car on a pair of 10.5 front rims. So I took the rims to the shop and had the tires mounted. I was putting them on the car getting ready for a trip (to the track) and realized I'd messed up taking the rims out of storage and one tire was mounted on a 10.5 front rim and the other one was on a rear 11" rim. So, rather than bail on a track day, I put a 35mm spacer under the 11" rim and a 3mm spacer under the 10.5. Now both had identical 27mm offsets. It drove fine. When I got home from the track day, I had the tire switched to a 10.5 and it's been that way ever since.

Sponsored