2006 Ford GT Tire/Rim fitment limit without spacers?


Daniel_Iaciu

Member
Jun 4, 2025
20
Romania
Hello! Im opening this thread to get clarification on a tire/rim question I couldn't find the answer too.

I bought a Ford GT with the stock rim sizes but aftermarket tire sizes + spacers on it. I wanted to know if stock rims + 265 35 18 fronts and 345 30 19 backs will fit without the spacers? I intend to keep stock rims for backup/winter tires regardless, the current setup is too small in diamater so I am gonna change it to nearly stock diamaters to avoid guage misreading speed.

Also, I purchased a set of rims that are 19 inch fronts and 20 inch backs, with 0.5 inch increase in width VS the stock 18/19 width. Would these sizes fit without spacers?

Or does anyone know what the width limit is on the ford GT without spacers before it starts rubbing on insides?
 
I bought a Ford GT with the stock rim sizes but aftermarket tire sizes + spacers on it. I wanted to know if stock rims + 265 35 18 fronts and 345 30 19 backs will fit without the spacers?
In case you're not aware, the 265 and 345 figures indicate the tires' approximate width in millimeters. And the 35 and 30 are percentage figures that indicate the tires' sidewall heights as a percentage of their widths.

Fronts: If the front rims are stock sizes and offsets, since we know Bridgestone RE050A Potenza (Porsche N1) 265/40R18 front tires fit you "shouldn't" need spacers at the fronts, but the previous owner might've thought it made the wheel / tire combo fit the fenders tighter and look better. Also, the 35 figure indicates the 265 35 18 front tire is probably a little smaller in diameter than the Bridgestone RE050A Potenza (Porsche N1) 265/40R18 we know fits properly.

Rears: Similarly, if the rear rims are stock sizes and offsets, since we know Bridgestone RE050A Potenza Scuderia 345/35R19 rear tires fit you "shouldn't" need spacers at the rears, but again the previous owner might've thought it made them look better. And, the 30 figure indicates the 345 30 19 rear tire is probably a little smaller diameter than the Bridgestone RE050A Potenza Scuderia 345/35R19 we know fits properly.

Someone else will need to reply re whether or not the smaller diameter tires will actually cause any problems; they might just look a little small, but I don't know.

Also, I purchased a set of rims that are 19 inch fronts and 20 inch backs, with 0.5 inch increase in width VS the stock 18/19 width. Would these sizes fit without spacers?

Or does anyone know what the width limit is on the ford GT without spacers before it starts rubbing on insides?
Sorry, I can't answer either of these.

Posting the tire makes / models here would prob help us.
 
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In case you're not aware, the 265 and 345 figures indicate the tires' approximate width in millimeters. And the 35 and 30 are percentage figures that indicate the tires' sidewall heights as a percentage of their widths.

Fronts: If the front rims are stock sizes and offsets, since we know Bridgestone RE050A Potenza (Porsche N1) 265/40R18 front tires fit you "shouldn't" need spacers at the fronts, but the previous owner might've thought it made the wheel / tire combo fit the fenders tighter and look better. Also, the 35 figure indicates the 265 35 18 front tire is probably a little smaller in diameter than the Bridgestone RE050A Potenza (Porsche N1) 265/40R18 we know fits properly.

Rears: Similarly, if the rear rims are stock sizes and offsets, since we know Bridgestone RE050A Potenza Scuderia 345/35R19 rear tires fit you "shouldn't" need spacers at the rears, but again the previous owner might've thought it made them look better. And, the 30 figure indicates the 345 30 19 rear tire is probably a little smaller diameter than the Bridgestone RE050A Potenza Scuderia 345/35R19 we know fits properly.

Someone else will need to reply re whether or not the smaller diameter tires will actually cause any problems; they might just look a little small, but I don't know.


Sorry, I can't answer either of these.

Posting the tire makes / models here would prob help us.
Hello! Thank you for answering. Yes, both of the tires would end up being 1-3% smaller in diameter then OEM. The 345/30/20s come out to 28.1 inches in diameter, and the 255/35/19s come out to 26.0 inches. The car is on a KW suspension, and as a result, ever so slightly lower then stock, but it's adjustable so fender gap can be adjusted if diameter looks too small.

If the sizes you mentioned fit with no spacers that's great, because from what I checked the setup I ordered won't be any wider or taller then those. The tire models are Michilen Cup 2 for both front and back in the sizes stated right above.

I also suspect previous owner just thought car looked better with spacers and put them on just for looks, but I had to make sure, thank you😂
 
Daniel, the offset of the wheels is important too. If the 19 and 20 wheels have the same offset as the original 18 and 19 wheels, you should not need spacers.
 
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Daniel, the offset of the wheels is important too. If the 19 and 20 wheels have the same offset as the original 18 and 19 wheels, you should not need spacers.
I bought a set of larger rims that are forged and look identical to OEM but just add an inch of rim diamater. They are meant just for the car and didn't specify needing spacers, but I didn't see the offset actually, so I'll double check it.
 
Curious how long were the spacers?
I have stock wheels with Bridgestone
  • 265/40R18 fronts
  • 345/35R19 rears
I have H&R 25mm spacers in the rears and trying to get 20mm spacers in front but the OEM bolts are about 1-2mm too long
 
Curious how long were the spacers?
I have stock wheels with Bridgestone
  • 265/40R18 fronts
  • 345/35R19 rears
I have H&R 25mm spacers in the rears and trying to get 20mm spacers in front but the OEM bolts are about 1-2mm too long

Do you mean the H&R bolts were too long?

How about open face nuts?
 
Do you mean the H&R bolts were too long?

How about open face nuts?
No, the actual OEM bolts thread through the spacers and are barely touching the back of the rim….
I can try to take pics but still figuring out how to upload photos on this forum…
I suppose I could change out to extended bolts but didn’t want to go through that hassle
 
No, the actual OEM bolts thread through the spacers and are barely touching the back of the rim….
I can try to take pics but still figuring out how to upload photos on this forum…
I suppose I could change out to extended bolts but didn’t want to go through that hassle

Oh, too short. Yeah, I looked into swapping to longer ARP’s. Entire hub assembly has to come off to do it.