getting a 245/45/17 to fit on the front

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Even with perfect backspacing, not gonna happen. This is the tire chart for maximum unmodified tire size. The tires you suggest will require rolling the lip, and probably even flaring the fenders.

65-70Tyreandwheelsize.gif
 
right now the wheels are stock mach 1 17x8 wheels with 5 3/4 backspacing. I got a set of 1.5" wheel spacers that I was going to mill down to 1" right now and see how they fit. I'm thinking i could get by with 4 3/4" backspacing on the front if i maybe roll the fender lip
 
I don't think I would trust that list entirely 100% of what WOULDN'T fit for sure. It has quite a few sizes not on there we've put on personally. Like 18x9 on a 275 on the rear of a 65 or 315's on the rear of a 67-70
 
picked up some 17x8 wheels. What kind of backspacing do i need to fit a 245/45/17 tire on the front of a 65?


i think it will fit. Maybe some loss in turning. My 65 mustang has a 245 tire in the front. But on a 7 inch wheel. My 65 falcon has my own design custom front suspension. With 7.5" wheels 245 tires and 4" backspace. The car is lowered 3" and the tire just fits everywhere.






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If you:

1. Downsize to a 245 40 17
2. Perform Shelby drop
3. Run a stiff spring and good shock (I have 620 drop springs and IAS shocks)
4. Run an aggressive alignment (-2 camber)
5. Use 4.75 backspacing

You can run them without rolling your fender lips ;)
I can say that with some certainty since this is what I run.
 
That just goes to show you how these issues are not cut and dry. My car has a 1" drop, agressive springs rolled fender and I had to change to 225's on mine. One side would clear and the other was no where even close and even bent the fender. I have 4.75" backspacing also.....:shrug:
 
That just goes to show you how these issues are not cut and dry. My car has a 1" drop, agressive springs rolled fender and I had to change to 225's on mine. One side would clear and the other was no where even close and even bent the fender. I have 4.75" backspacing also.....:shrug:

Judging by your sig photo....you have 0 camber (maybe even positive). Did you provide alignment specs to your shop or just ask them for an alignment. The stock specs for the car are no longer all that good after the shelby drop and the addition of modern tires.
 
don't be too sorry if you can't fit, 245s can = bumpsteer

picked up some 17x8 wheels. What kind of backspacing do i need to fit a 245/45/17 tire on the front of a 65?

Coming from someone who's done this, don't be surprised if you have bumpsteer issues with a low profile 245 tire up front. If you have any bumpsteer at all or "tramlining" you'll have lots more with the 245s . . . oodles, even. :D

It's not the end of the world if you can only fit, say, 225s or 235s, especially with a higher profile tire and on a car you want freeway stability with.
 
Dodgestang, You are correctly in that I had the best shop in town do my car while those 245's were on installed....I had to use one of my rollbacks to take it to him though as it was undrivable. I left the specs up to him as I had basically given up on them fitting and he agreeed that they would never fit my car. Having said that back in high school I hit a curb really bad on the passenge side so bad the car would not steer to the left and now I wonder if that played a part as thats the side that hit the fender. That impact was bad enough that the front of the car was damaged (Fender & Valance) along with steering componets.....I cant believe I didnt think of this when dealing with this back in 2004.

One other issue that may play a part is my baer brakes which obviously included different spindles and hubs????
Either way, the 225s are great and I like the look better with the old school old of wider tires in the rear.
 
well i had some 1.5" spacers lying around. I threw on one side to see how much i'd like to remove. I'm going to machine the spacers down 1/2" all the way around to give me a total of 4 3/4" backspacing on a 17x8 wheel with 245/45/17 tires. I'll roll the front if I can, if not get smaller tires...i'm limited by getting the wheel in the wheel well more because it looks like if I go more than 4 3/4" backspacing the wheel is going to hit the upper control arms

I freaking LOVE these wheels. Factory mach 1 wheels off the newer mustangs
View attachment 241165
 
very sharp looking car. I was wondering why you're deadset on running 245's in the front?
i like big tires...plus they are already on the wheels!!

Its my brothers car, he asked me if I could sell it for him since he just found out they are expecting a 2nd baby, so the first thing i had to do was get the disgusting centerline aluminum hole wheels off that were on it....car looks unbelievably better now.

Anyone know what the going rate on a 65 a code 289/4speed shelby clone is? Clean, nice driver, runs/drives like a champ, and its got the cool late 65/66 gauges
 
right now the wheels are stock mach 1 17x8 wheels with 5 3/4 backspacing. I got a set of 1.5" wheel spacers that I was going to mill down to 1" right now and see how they fit. I'm thinking i could get by with 4 3/4" backspacing on the front if i maybe roll the fender lip

Be careful milling them down. I had some 1.5's that I milled down to 1 inch, and when I was done, the flange between the lug nut and brake rotor was too thin, it wouldn't hold. So I just ruined that expensive billet wheel spacer. I can grab a pic of it tomorrow if you don't get what I'm talking about.
 
Watching the HorsePower TV episode where they're building a track car out of a '67 Dynacorn shell, and they have an interesting way to measure wheel fit. DVR it if you can, but a little summary:

1. Find out your wheel backspace.
2. Take your tire diameter and cut it in half, getting the radius.
3. Take a long piece of wire and make an "L" bend in it at the backspace point - say, 4.75"
4. Attach wire to the center of the wheel hub, (with the wheel off) at the radius distance from the "L" bend - tape should be fine.
5. Turn the wheel to check the interference of the "L" bracket and at various positions.
6. Do the same the opposite way for the fender lip clearance, but subtract the 4.75" backspace from the total width of the wheel. An 8" wheel is usually 9" wide, so 9-4.75=4.25".

I can take a pic from the Horsepower TV episode if you want . . .
 
Be careful milling them down. I had some 1.5's that I milled down to 1 inch, and when I was done, the flange between the lug nut and brake rotor was too thin, it wouldn't hold. So I just ruined that expensive billet wheel spacer. I can grab a pic of it tomorrow if you don't get what I'm talking about.
yea thats why i took .25 off each side of the spacer cause it would have been too thin if i took the .5 off of the back. I wanted to take the .25 off the side that mounts to the hub also since the i didnt like the lack of thread engagement on the adapter/spacer since the lugs are not that long.