Stuffing 275's into a GTPE

General Information

MAKE
Ford
MODEL YEAR
2021
MODEL & TRIM
Mach-E GTPE
COLOR
Cyber Orange
Standard Range / Extended Range
Extended
AWD / RWD
AWD
PACKAGES
GTPE
FACTORY OPTIONS
Performance Edition: Magneride, flow-forged wheels, Performance Seats, body-colored roof, no sunroof
MODS - SUSPENSION / CHASSIS
Steeda rear sway bar
MODS - WHEELS / TIRES / BRAKES
MRR FS06 forged flow-formed wheels, General G-Max RS tires, 275/40R20 XL
MODS - EXTERIOR
Racing stripes, paint protection film, ceramic coat on body and wheels
MODS - INTERIOR
Schroth 4-point racing harness, felt console bins
HISTORY, STORY, EXPERIENCE, COMMENTS
Lots of wheel and tire guys say you can't put 275's into a GTPE, at least on the front. But I did it! I used MRR FS06 20"x9" forged flow formed wheels, with (this is IMPORTANT!) a +35 mm offset, i.e., an ET35 setup. This gave me a finger's clearance on the inside edges of the wheel wells. Why not go with 295's on the rear? Because I'd need a wider wheel on the rears, which would disallow tire rotations (10" wouldn't fit on the front), and most importantly, GTPE's already understeer, so why would I add more? I bought the new adjustable Steeda anti-sway rear bar, to dial out the existing (pre-wheel/tire change) understeer (increases the rear anti-sway from 200 pounds to 250-300-350 pounds).

Why not use forged? I got two bids on fully-forged wheels, with one quoting $1500/wheel, and the other $1250/wheel. Neither would guarantee fit. The MRR's were $590 each, including free shipping! MRR also said that 275's wouldn't fit on a GTPE...which just means that they hadn't gotten word that it would work from an end-user. The forged wheels weighed about 23-24 pounds each...the 9" MRR's weighed 26.2 pounds (I weighed the MRR's myself on a digital scale). That compares to the stock GTPE 8" forged flow-formed wheels at 29.5 pounds.

MRR uses different procedures from other wheel manufacturers. They have the wheels built in Taiwan (like everybody else), but the wheels are shipped in an uncompleted state. The offset, bore, surface treatment and powdercoats haven't been done yet. MRR pre-orders many, MANY of these unfinished wheels, and stores them in Caliifornia. Then, when you order the wheel you want, you get to specify the bore, offset, surface finish and color yourself. They then finish making the wheel in California. Whereas the other two wheel companies specified a 4-6-WEEK wait for the wheels, MRR specified a 6-DAY wait! My wheels, which had an extra custom finish, involving extra labor (and cost), were ordered at 4:30 pm on a Friday, and delivered to me 8 days later, on the next Saturday, at 12:30 pm. Did I mention the shipping was free?

The wheels came with a 66.6 mm hub bore, and the Mach-E's have a 63.4 mm hub. My fault, I didn't specify the hub bore...I would specify a 63.7 mm bore if I did it again. I added 63.4 mm-to-66.6 mm hub ring adapters (plastic), so the lug bolts wouldn't be carrying all of the weight.

I worried about how hard it would be to force 275's onto 9" rims (the wheel specs for these tires say 9"-11" wheels are okay). So I coated the outsides of the wheels (1 coat), including the TOP OUTER EDGE, and the inner surfaces of the barrels (2 coats) with Gyeon Rim Q2 ceramic coat. The Gyeon Rim ceramic is a special high-temp coating, made to withstand the high heat from brake calipers. So far, brake dust doesn't seem to stick. When I finished the coatings, the insides of the rims felt like glass. Note that this is a "Pro" coating ($50 on Amazon), but I had no problem applying it. NOTE: On YouTube, the guys showing you how to apply it are doing it wrong...they're applying it much too heavily (I had NO "high spots" when I did it). Just read (backside of the front label) the directions, and follow them, and watch the application video Gyeon has on their website. I had enough of the rim ceramic "vial" left to maybe do 1 additional coat on 2 more wheels.

My tire guy (Premier Mobile in W. Sacramento...find him on the Tire Rack site) said that he had no problems getting the tires on..."probably due to the ceramic coat". Note that I put NO ceramic on the inside edges of the wheel lips (where the tire rests against the rims).

Finally, I had to do a very slight mod to the inner rear felt fender liners. They hang loose from the inner wheel-well metal, and have about a .5" gap between the felt and the metal. I used a 6" piece of black gaffer tape to pull the felt back to the inner well's metal at one point. If you crank the front wheels to the extreme left or right, you can hear a very slight rubbing on the felt liners, but only from a dead stop (like exiting a parallel parking space). I hear no rubbing while cornering, fronts or rears. And no scraping on the front wheel well lips...no grinding necessary! Gaffer tape is like duct tape, but it's stronger and has a MUCH stronger adhesive. I hung some paintings temporarily on a set wall once, with small loops of gaffer tape, and it pulled the outer-and-middle surface of the drywall off. Sold at motion picture supply stores in Hollywood.

Results? My GTPE corners much harder before slipping. And the car feels MUCH more planted on the road (probably due to both the increase from 245 to 275 in width, and the decrease from 45% to 40% on the aspect ratio). General (owned by Continental, who also owns Hoosier) G-Max RS's came in third in Consumer Report's "High Performance Tire Tests", slightly behind Michelin Pilot Sport 4S's and Pirelli P Zeros. Their wet braking was better than either of the others.

Cost? I got the G-Max's for $196 each, when the Pirellis were $348 and the Pilot Sports were $379. AND the G-Max's have a wear rating of 350, which I feel that our heavy cars need. Tire noise is slightly more (5%), and the ride is slightly stiffer (5%). They have a 10.82" tread width. Range? I'm doing a mountain drive from Tahoe to Nevada this weekend, and will report back.

Comments

Greek to me. But I really like the look.
 
I was the the first Mach-E EVER entered into a Mustang Club of America national competition, as a competitor (not display-only). Result was a President's Choice Gold Award.
20220522_211504.jpg

BTW, so far, my range with the wider tires (275 vs 245) and custom wheels, has been reduced from 254-256 to 250.
 
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I was the the first Mach-E EVER entered into a Mustang Club of America national competition, as a competitor (not display-only). Result was a President's Choice Gold Award.
20220522_211504.jpg

BTW, so far, my range with the wider tires (275 vs 245) and custom wheels, has been reduced from 254-256 to 250.
Congratulations on the fitment and the award!!! Sounds like it was rather fun. And you obviously did your homework regarding the fitment.

Question for ya'. I'm considering a 265/30r22 and 22x9 with 32ET for my MME GT. Taking your config into consideration and based on my own research using tiresize.com and wheel-size.com, I'm thinking I'm good. Though the ride may be a bit stiff and hopefully I can serpentine around the occasional pothole.

Anyway, I expect the outer edge where the flat tread begins (meets the sidewall) should line up pretty flush with the outer fender flare and the sidewall's should poke out about 1/2" which would be pretty close to perfect, IMO. And of course I'm hoping no rubbing during extreme turns.

Care to share your thoughts and/or concerns?

Thanks and much appreciated,
 
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Congratulations on the fitment and the award!!! Sounds like it was rather fun. And you obviously did your homework regarding the fitment.

Question for ya'. I'm considering a 265/30r22 and 22x9 with 32ET for my MME GT. Taking your config into consideration and based on my own research using tiresize.com and wheel-size.com, I'm thinking I'm good. Though the ride may be a bit stiff and hopefully I can serpentine around the occasional pothole.

Anyway, I expect the outer edge where the flat tread begins (meets the sidewall) should line up pretty flush with the outer fender flare and the sidewall's should poke out about 1/2" which would be pretty close to perfect, IMO. And of course I'm hoping no rubbing during extreme turns.

Care to share your thoughts and/or concerns?

Thanks and much appreciated,
According to tiresize.com, that fitment should work. But here's some thoughts:

1. There's only 2 tires available from tirerack in that size, and one is a run-flat. I would never recommend a run-flat, due to the ride stiffness. With that tiny sidewall, you'd have iron tires.

2. There are no snow tires in the 265/30R22 XL size.

3. The look would be really cool. But the ride will stiffen up a LOT, and I mean by a HUGE amount. With so little compliance in such a short sidewall, you may start breaking other components, like shock mounts or sway-bar mounts.

4. Your speedo will be off by 1 mph at 70...no big deal, just back your speed off by 1 mph.

5. If it were me, I'd stick with 20", and spend a bunch of money on some REALLY custom wheels, say, 3-piece with a fun color combo. That would let me be one-of-a-kind, but not limit my tire selection so much. And it would preserve the ride quality...too-stiff will have you chattering across the corners. Nobody wants an evil-handling car. Take a look at signaturewheels.com, they have images of some interesting multi-color wheels on-site.

Good luck!
 
Thanks for the thorough reply. Yeah, I was nervous about the 22's. It was with the XO Luxury Phoenix wheel which is pretty cool looking but pricey for me.

I had my heart set on some 21" wheels but tire selection is so minimal and pricey. For the 21's, my sidewall height would have gone from 4.3" down to 3.7" which would have been ok. Going to a 22" wheel brings the sidewall down to 3". And I really don't want the fillings in my teeth to rattle loose.

Considering my current situation with the GT, last night I purchased a set of MMR GF9's in silver, 20x8.5 with a 35ET and I'll keep the OEM Continental all-season tires on that.

It's a conservative choice but I need to consider resale value since I'm hoping to be taking delivery of my new Rivian truck in about 6 - 8 months. The GF9's are a wonderful substitution for the goofy flower child wheels that come with the GT. But I just can't see myself driving on those silly OEM wheels for more than a week or so. It's kinda' embarrassing. :)

Anyway, thanks much for your input.
 
BTW, can you tell me what size lug nuts I need for the GT? I know it M14x1.5 but some seem to indicate I need "tall" lug nuts for the GT. The OEM lug nuts are chrome and I need black.

Could you possibly provide a link where you got your lug nuts?

Thanks and much appreciated.
 
BTW, can you tell me what size lug nuts I need for the GT? I know it M14x1.5 but some seem to indicate I need "tall" lug nuts for the GT. The OEM lug nuts are chrome and I need black.

Could you possibly provide a link where you got your lug nuts?

Thanks and much appreciated.
These are what I used (mine are chrome):

https://www.americanmuscle.com/6spline-lugnuts-black-1516.html

They have taller ones also. MRR says that their wheels will take the regular Mach-E GT nuts, but my tire guy told me that, NO, the OEM nuts wouldn't have fit.
 

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