OK, my Bad.- Still working on my MK4 and last week I finally ordered tires (online) for my 17X9 Halibrand replica wheels - 255/45/17 for the front and 275/40/17 for the rear. I was thrilled when they arrived and had them mounted right away. Today while working on the car, I realized that I have 255/40/17's on the front instead of 255/45/17! I was always a terrible proof reader, and I overlooked what was on the tire as well as the invoice. All I saw was 255 and 275/ 17.
I haven't contacted the supplier yet to see if I can return the front 2. But I was also wondering if there would be any problems running 255/40's on the front ? From the specs, the 40 series tire is 0.2" wider in section with, half an inch wider on the tread and 1.1" shorter in the overall diameter vs the 45 profile.
What can I expect in terms of fender clearance/rubbing, and would ther be any adverse effect in the car's handling ?
You’re better off with a 255/40 than a 255/45...255/45 is too tall. If you’re going to run a 45 series it needs to be 245 (which in my opinion is a little stretched on a 9” rim.
Now, about those 275s; I don’t like to see them on a 10 or 10.5” rim...again they’re stretched with the rim being wider than the tread. If you’re putting them on a 9” rim you’ll be good to go.
Jeff
Last edited by Jeff Kleiner; 07-01-2020 at 06:09 PM.
The 40 or 45 series number has to do with the ratio of the sidewall height to the section width. A 255/40 is the same width but with a shorter sidewall than a 255/45.
358 SBC, Winters QC, Sweet mfg, Coleman, AP Racing, ARS, TKO 600, Fuel Safe
I've read your past posts regarding tire sizes and from what you have said it looks like I made a happy mistake. Wheels are 17X9 all around, so I shoud be good to go after all.
Wheels are 17X9 all around, so I should be good to go after all.
Tom,
Since you have 17 X 9's on all four corners, have you considered running 255/40-17's up front with 275/40-17's out back?
That's the combo we have on Baby Go-Dad Catfish Camaro and it looks just fine.
He's running 17 X 9.5's wheels on all four corners.
Uh, Steve...that's what he IS running. I think looking at all that new shiny red paint has fogged your mind and messed with your comprehension abilities
Uh, Steve...that's what he IS running. I think looking at all that new shiny red paint has fogged your mind and messed with your comprehension abilities
Jeff
You're Probably Right!
I was at the body shop today because I had them spray the louvers too.
I'm not accustomed to being around fumes so you may be on to something.
I only get loopy when I’m NOT breathing fumes! I once had an old girlfriend who used to tell people she didn’t know I drank until she saw me sober! It’s kind of like that
Do I need to be concerned about any tire rubbing with the 255/40/17 on the front? The stats say the section width at 10.2", same for the tread, and 25 inches OD. The 275 rears are 10.9" section/10.2" tread and 25.7" OD
Do I need to be concerned about any tire rubbing with the 255/40/17 on the front? The stats say the section width at 10.2", same for the tread, and 25 inches OD. The 275 rears are 10.9" section/10.2" tread and 25.7" OD
A pile if guys have 255/40-17 and 255/35-18 (Both Are Around 25.0" Tall) on the front of their MK-4 Roadsters.
I'm running 245/45-17, on 9.0" wheels which are about 25.6" tall and can be viewed below:
My ride height is 4.0" up front and 4.4" in the rear.
The rears tires are 285/40-17's on 10" wheel and they are 26.0" tall,
285's can be squeezed these on a 9.0" rim; however, it isn't recommended.
No, You do not need to worry about rubbing with the 255/40/17 Mine do not rub the fenders or F panels lock to lock.
I am running 255/40/17 in the front and 315/35/17 in the rear.
Originally Posted by zilverx
Thanks everybody. Appreciate the input!
Do I need to be concerned about any tire rubbing with the 255/40/17 on the front? The stats say the section width at 10.2", same for the tread, and 25 inches OD. The 275 rears are 10.9" section/10.2" tread and 25.7" OD
F5R #7841: Anniversary Edition MK4, Ford Racing 427, Edelbrock EFI, Gas-N Pipes, Stainless Headers, TKO600, 3.31 Moser 3-Link, 17" Halibrands
There will be a slight variance in my actual numbers because both sets are on wheels .5" narrower than the wheels NITTO speced them on.
Tires clear the Mk-VI body/chassis. Had to adjust one flexible brake line that rubbed at full right lock.
Current ride height 4" in front & 4.5" in rear. Found this is good for most speed bumps.
Words of caution. These are fresh tires for me & will take them to a big empty parking lot to get a feel for them first day out. Have been running Nitto 555R DOT compliant & barely street legal tires since I built the car. They are sensitive to rain & if you get caught in a shower you need to drive like you have regular tires on snow. The are also sensitive to cold weather. Mine got skidish around 40*F. Buy skidish I mean a sharp input can create an "Oh ****" moment. My learning experience was a quick 1/2 shift on a cold morning going to a Cobra Coffee. Was not going fast & did not have very high RPM's but let the clutch out a little to quickly & the car stepped right out & tried to eat the median. Got it under control quickly so no harm no foul just an elevated heart rate.
Last edited by BEAR-AvHistory; 07-03-2020 at 10:33 AM.
Kevin
MKIV #8234
Coyote '14/TKO-600/3-Link 3:55 Rear I love the smell of 100 octane in the morning.
NITTO NT01 275X40X17ZR - 315X35ZRX17
Delivered 2/7/14 - Plate "COYOTE NC1965" 3/25/15
Regarding caster, I'm midway through trimming the upper control arms as I have power steering.
Tom
Then you should be good. The first point of tire to body contact is the leading edge of the wheelwell and this generally becomes a non-issue when you get into the higher caster ranges (6 to 8 degrees) with power steering.
I can trim them in my lathe if you want. Send me a PM and I'll return it w/ my address. Put them in a bag or box w/ $10 to cover return postage.
CraigS,
Thanks, I appreciate the offer but we have a shop that takes care of our MGB, and they were able to give me some nice square cuts. The control arms are back together and I'm on to the next details.
I am looking to use that same tire combo (255/40/17 Front, 315/35/17 rear) but wondered how they fill the wheel wells. Do you have a pic that is taken more from the side of the car that you can share?
Thanks,
Rich
No, You do not need to worry about rubbing with the 255/40/17 Mine do not rub the fenders or F panels lock to lock.
I am running 255/40/17 in the front and 315/35/17 in the rear.
Hello CDXVVII,
I am looking to use that same tire combo (255/40/17 Front, 315/35/17 rear) but wondered how they fill the wheel wells. Do you have a pic that is taken more from the side of the car that you can share?
Thanks,
Rich
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Originally Posted by zilverx
I just want these tires to work -
