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19x11.5 Square?

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I know that there was a guy on another forum that was running an 18x12 square setup on a GT with 315/30R18 tires. Last I saw he was moving up to 13" wide. I'm currently running 19x11 square on my GT. With the wider front fenders on the GT350 I wouldn't think it would be much of an issue to go 1/2" wider.
 
1,246
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In the V6L
If the offset is right, the width of the rim isn't as important as the width of the tire. It's the tire that has to fit in the space available. If you can run 305 square on 11's, then the tires will be about 3/8" wider on 11.5's, and the extra 3/16" on each side of the tire will probably still fit without hitting. But if you take advantage of the extra rim width and bump up to 325's, you might find they're ok if you squeeze them onto 11's but it's possible that they'll sit too wide on 11.5's. Be prepared for some trial and error.
 
I know that there was a guy on another forum that was running an 18x12 square setup on a GT with 315/30R18 tires. Last I saw he was moving up to 13" wide. I'm currently running 19x11 square on my GT. With the wider front fenders on the GT350 I wouldn't think it would be much of an issue to go 1/2" wider.
What offsets are you running if I may ask?
 
If the offset is right, the width of the rim isn't as important as the width of the tire. It's the tire that has to fit in the space available. If you can run 305 square on 11's, then the tires will be about 3/8" wider on 11.5's, and the extra 3/16" on each side of the tire will probably still fit without hitting. But if you take advantage of the extra rim width and bump up to 325's, you might find they're ok if you squeeze them onto 11's but it's possible that they'll sit too wide on 11.5's. Be prepared for some trial and error.
I’m running 305/690 pirelli slick and find they need a wider wheel. I just got a set of 315/705 pirelli slicks and could use the extra width.

Just measured and mocked up the current wheels with various spacers and I know the 19x11.5+56 out back will work.

Fronts look promising as well with 19x11.5+56 and 30mm spacer.
 

boardkat

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I know that there was a guy on another forum that was running an 18x12 square setup on a GT with 315/30R18 tires. Last I saw he was moving up to 13" wide. I'm currently running 19x11 square on my GT. With the wider front fenders on the GT350 I wouldn't think it would be much of an issue to go 1/2" wider.
it's actually a 335 on 18x12 swquare that i've been running the past few seasons :)
and yes, my 18x13 square setup arrives friday (finally! i spec'd and ordered the damn things on 10/31). pics and fitment notes soon :D
 
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What offsets are you running if I may ask?

For my 19x11 square setup I'm running a 50mm offset with a 20mm spacer up front. I'm most likely going to be going to a 15mm spacer since my coilovers have more room than I thought to move inboard. I wish I had the wider front fender like the GT350.

it's actually a 335 on 18x12 swquare that i've been running the past few seasons :)
and yes, my 18x13 square setup arrives friday (finally! i spec'd and ordered the damn things on 10/31). pics and fitment notes soon :D

There we go. I knew it was something wild like that!
 
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DFW, TX
This is what I was wanting to try eventually. It sure looks like there is more room in the front, than the rear on a GT350 when running track camber settings. I was going to throw on my extra 10mm spacer on top of the 28mm one I'm running for the square 19x11 et 52 setup to estimate. You could do 34mm spacer and et 56 R wheel with an R model front hub. 30mm is the max spacer width that motorsport-tech can make according to their website.

DOT tires selection is very limited however with the 315 SC2 being the widest tread, lesser section width choice. Many of the 325 tire's section width may prohibit their use.

There are just so many more 305 tires choices (and I got the $200 Wal-Mart deal on 305 SC2s) that along with the Apex price that I could not bring myself to spend the extra money. Someday...

Let's see if they come up with a different rear tire choice on the GT500!
 
1,246
1,243
In the V6L
If you want thicker spacers, you can buy double bolted ones from Eibach or H&R and just punch the wheel studs out. I have a pair of Eibach 35mm spacers that I use with OEM 11" ET62 rear rims on the front.
 

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Cool discussion going on here.

When running our EC-7 19x11" ET52 in a square configuration, most enthusiasts (S197, S550 & S550 GT350) are running 25mm spacers up front for proper strut clearance. That gives us an effective offset up front of ET27.

If we compare that with a 19x11.5" ET56 and 30mm spacer (effective offset of ET26), the 11.5" wheel will have 5mm LESS clearance towards the suspension, and will EXTEND by 7mm towards the front fenders. Whether or not we can give up that 5mm on the inside is really dependent on what suspension is present, as well as the tire brand/size. With stock struts, I do not see this as feasible solution. We know the GT350 can accommodate the extra 7mm on the outside due to the wider fenders, however the "standard" S197 and S550's would need really aggressive camber specs to prevent rubbing / damage to the front fenders under load. The 11" wheel with spacers and healthy negative camber specs are already very flush with the front fenders.

In some cases, customers running our 19x11" ET52 were able to get away with slimmer 20mm spacers (or even 15mm). This is likely due to slimmer tires being present, or aftermarket suspension that offers more inner clearance than the factory struts.

If we compare that with a 19x11.5" ET56 with a 30mm spacer (effective offset of ET26), the 11.5" wheel will have THE SAME inner clearance towards the suspension, and will EXTEND by 12mm towards the front fenders. This proves that aftermarket coilovers that provide extra inner clearance will be vital for this fitment to work.

It is important to note that the above information only takes into account the wheel itself, and not the tire.

We (APEX) have been brewing over the release of a 19x11.5" ET56 wheel for some time now. The main concern I've had with offering an 11.5" wheel is whether or not the superior sidewall support achieved with a 305 tire is enough incentive to warrant a heavier, slightly more expensive wheel which requires even thicker spacers. As mentioned by other enthusiasts above, I do not think it is feasible to run 325's on all four corners without a good amount of work, so those tires likely only come into play for those running staggered configurations.

Track Tire Options to Consider

305/30-19
Nitto NT01
Michelin Pilot Sport Cup 2
Toyo R888
Toyo R888R
Dunlop Sport Maxx Race
Pirelli Trofeo R

315/30-19
Michelin Pilot Sport Cup 2

325/30-19
Nitto NT-01
Eagle F1 Supercar 3R
Michelin Pilot Sport Cup 2
Pirelli Trofeo R
Hoosier A7 & R7
Toyo R888 & R888R

One added benefit is that we could offer this wheel to GT and GT350 owners looking to run them in the rear, as a staggered setup. The combined interest of hard core track enthusiasts and racers (square) and your day to day street enthusiast (staggered) may create enough demand for something like this to exist.

- Ryan
 
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I plan to try this. I have a 305 on a 10.5 now and its to much. Ive been running the 305 Re-71r and relaxed before mounted they are 11 3/4", so Id like to try a 11.5 wheel to keep them as square as possible.
 
Just out of curiosity, what issues are you running into with the 11" wheels with the Pirellis? I'm thinking of running a similar config.
Thanks!
I’m running 305/690 pirelli slick and find they need a wider wheel. I just got a set of 315/705 pirelli slicks and could use the extra width.

Just measured and mocked up the current wheels with various spacers and I know the 19x11.5+56 out back will work.

Fronts look promising as well with 19x11.5+56 and 30mm spacer.
 
I'd assume he's implying that they're pinched a little on 11" wheel which means they'll feel slightly mushy and also wear the shoulders out due to the carcass rounding over instead of sitting up square.
 

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