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65 GTO Wheel Size

22K views 33 replies 4 participants last post by  renorealtors 
#1 ·
I am at the point of ordering wheels and wonder what is the go to size for wheels and tires on a GTO with big brakes. I think 17" will fit but there has to be a size that will give me the most width but not rub. My 65 Chevelle was tight but 18" IROC looking wheels fit on it with just a bit of rub in tight turns. Does anyone have any ideas or been there choosing sizes? I took my Z06 front wheel off and tried to fit it but it was way to wide?
 

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#4 · (Edited)
Okay, I have posted my results in another post about "Rim" size and tire size. I am running 17"x9.5" in the rear and 17"x8" in the front. Tires are 275x40x17 in the rear and 225x45x17 in the front and absolutely no rubbing issues anywhere. I am running stock suspension for now, but just ordered a coil over kit from Viking, which I'll install as soon as it comes in.
 

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#5 ·
Okay, I have posted my results in another post about "Rim" size and tire size. I am running 17"x9" in the rear and 17"x8" in the front. Tires are 275x40x17 in the rear and 225x45x17 in the front and absolutely no rubbing issues anywhere. I am running stock suspension for now, but just ordered a coil over kit from Viking, which I'll install as soon as it comes in.
Hey Joe! I too am looking at the Viking coilovers. Who did you buy them from and what bring rates did you get ? (I am considering the 550# front & 150# rear.) I also will be installing inexpensive front upper and lower control arms (ebay) and Spohn rear del sphere (think heim joint) arms, along with new centerlink and inner and outer tie rods.
 
#6 ·
The Viking kit I ordered is for a GM "A" body, '64-67'. The springs in this kit are street springs as I'm not racing and or auto crossing. I think you can get it with either regular or big block springs, depending on your motor. I am using my stock A arms and not replacing them. On the rear setup, re-using my original stuff as well. Already boxed and new bushing in my 4 link a couple of years ago and all are still in great shape. The main reason I am doing this is for stance and ride quality, the rear coil overs come with a two position setup for the shock, then you can adjust away to fine tune it after. The front I'm looking at dropping an inch to 2 inches and that is enough for me.


I ordered this kit through a local Resto shop, who are a dealer for Viking, and they ordered directly from Viking, so I got the dealer price which is nice. Remember, up here we have to pay tax, import duties and exchange rate on the dollar, so it adds up.

I'm away from home right now for work, doing training for a customer who just bought new Co-gen generator system, from my company, We're a CAT Dealership, so when I get back home this week, I'll find my order sheet and post the details.


Joe.
 
#10 ·
Lots of great info!

I have 17x8 on the front, 5.25" BS, 245/45-17. On the rear are 17x9.5, 5.75" BS, 275/40-17. This is a 65 Lemans, no alterations whatsoever on the wheelwells. I do have Baer brakes front and rear which push the wheel mounting flange out about 1/4," so subtract 1/4" from the backspacing numbers if you have stock brakes. This wheel combo looks and performs fantastic! I didn't think I could get so much tire in back, but a friend clued me into the correct backspacing, and it's available as a custom order on the American Racing TT2.

Will willwood brakes front and rear change the backspacing? I guess I will find out when I call American Racing?

Thank you for all the input.

I like the idea of big wide rear rubber but will propbibly go with a bit less just to be sure I get no rubbing issues.
 
#14 ·
Okay, so finished installing my new front and rear Coilover conversion this evening. I say it turned out pretty good, no lost or crushed fingers. Drove it for about an hour and will have to adjust the front drivers Coilover as I was getting a slight rub during full turn and going over some curbs. I have to say, the ride quality is great and the handling is vastly improved. I also like how the stance turned out, but like I said, a little more adjusting and it will be perfect.
 

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#18 ·
Joe - Looks great!

Any chance you measured your coilover setup before installation (so I could use that as a starting point) ? I might choose to go slightly higher than you did or more of a rake, but very close to your look.

It would be interesting if folks have cornered balanced this platform and figured out what is best.

My setup should arrive in a bit (2 week + cycle time :( ...) ....I can't wait to get to the suspension installed, but wished I had your garage / lift setup to make the job slightly less painful.

Thanks again for all of your help.

Chris
 
#23 ·
Chris, before I did the Coilover's, I measured 27.5" from level ground to the middle bottom of my front wheel opening. Basically right in the middle of my wheel opening. The rear I measured 26.75" from the ground to the middle of the rear wheel well. After I did the Coilover's the front is now 26.25" and the rear is now 27.25". I did have the front lower but with me sitting in the car, it compressed about .75" so I adjusted the front up about another full inch. I'll have to see how much it compresses over the next couple of days, may have to do some more small tweaks to get it perfect. But I am very happy with the ride and handling so far. Attached is a before and after pic, from the side, which gives a better view.
 

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#19 ·
Hi Joe and Chris,

I finally got the wheels from American Racing Yesterday. I am now picking tire sizes. The wheel size AR picked for the 65 GTO is 17x7 with 0 offset up front and 18x8 and 0 offset in the rear. I am wondering if that is "0" back spacing?? Can't be right. They look good and are not crazy wide. Any tire size you would recommend?

Thank you John
 

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#21 ·
Hi John,

The "0" offset is not back spacing, you'll need at least 4.75" in front and 5.00" for the rear, if you stay with the 17" and 18" rims. The offset is how far the face of the hub is either out or in towards the hub. Backspace is how far the outside edge of the rim sticks out from the hub face. Offset can be negative or positive. With "0" offset, the hub face will be in the exact middle of the rim. Hope that helps.
 
#24 ·
Hi Joe,

"The "0" offset is not back spacing, you'll need at least 4.75" in front and 5.00" for the rear, if you stay with the 17" and 18" rims."

So it looks like American Racing has sent me rims that will rub the fenders, the BS on the front is 4" and rear is 5"? If you were going to do 17" front and 18" on the rear you would go go the 17x7 -4.75"BS and 18x8 -5"BS or 18x9.5 5.25"BS?
 
#26 ·
They may still fit, depends on the tire size your using. With my setup, I went with 225x45x17's in the front on a 17x8.5 rim, offset is 0 mm and BS is 4.75" On the rear I have 275x40x17's, with an 17x9.5 rim. The offset on those is 0 mm and the BS is 5.00" There was no rubbing whatsoever, but now I just did coilovers front and rear, which dropped my GTO by a few inches, all the way round. So tire size will determine if your setup will rub, you may have to decrease the width of the tire, so they fit. Hopefully someone else will chime in and help.
 
#27 · (Edited)
Just installed my wheels and tires (245/45/17 front & 275/40/17 rear). The wheels are American Racing Torque Thrust II (polished) 17x8 (front) & 17x9.5 (rear). The tires are BFG GForce Sport C2. So far I like how the tires perform.

I will lower the front a bit when I install my new suspension, but plan on keeping the rear height as is. I am so happy they fit!
 

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#28 ·
Just installed my wheels and tires (245/45/17 front & 275/40/17 rear). I will lower the front a bit when I install my new suspension, but plan on keeping the rear height as is. I am so happy they fit!
They look great, you'll be happy when you get the coil overs done. I did a show last night in a small town north of me, about 90 Klm's each way and I have to say, the improved ride and handling was very nice.
 
#30 ·
Update 11/29/18 Motor is about to go on the dyno. Did all Butler stuff with a local machine shop building and dynoing it. How exciting! Stroker bottom end, edlebrock heads with some custom porting, cal cam from butler, big oil pan, roller everything,and more. The next step will be to get the motor/trany installed and send the frame back to the pint shop.
 

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#31 ·
Update 12/25/18 Just got the motor back from the machine shop after dyno work. Does anyone have a PDF or link for a 1965 GTO wiring harness?? Also a pic of a Street Tracker I just finished.
 

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#32 ·
Nice dyno graph! Can you provide some details on the motor (I see you have aluminum heads)? (Attached are diagrams for a 66. I will upload my paper diagram in a few minutes.) Thanks
 

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