[HALFWAY]

I am thinking about new rims and tires, mainly due to the limited choices for 14". 64 LeMans.

I was looking at 16" x 8" with a 4" backspace.

Anyone else using this size rims, do they fit in the wheel wells with no issues?

If this size works what is the proper tire diameter?

[tempest1964]

I am pretty sure that the factory 15 X 7 wheels had 4.25 B.S. So, if you go from there, an 8" wheel is an inch wider. To equally space the wheel in the wheelwell, it should have .5" more back spacing, about 4-3/4". That would center the wheel up like the 7" wheel. Just a 1/2 inch wider tread inward and a 1/2 wider tread outward. I went with Torque Thrust II's on mine. They were 17 X 8's instead of 16 X8's. They were available in 4.875 back spacing. Almost what I calculated. They are centered up pretty darn good. My tire diameter was based on the diameter of the tires I had on it. I liked the stance. They were 14's with a tire diameter of right at 26". I got 245-45-R17's. Almost the same diameter. It worked good on my '64 Tempest.

[HALFWAY]

Thanks for the info, I was going the wrong way on the backspacing

[The Champ]

Finding tires for 16" rims is getting almost as tough as finding 14's...

I would either go to a 15 or a 17" rim for better tire selection.

As for tire diameter - the OE tires for the '64 GTO were 27" tall. The LeMans would have been a little shorter - but there is room for the taller tires depending on how wide you decide to go.

If you are looking to run the same size front and rear with 16's - a 225/60/16 is 26.6" tall - a popular 16" size that was used on the Grand Prix from the late 90's on up.

[HALFWAY]

I finally purchased a new set of rims for the 64 LeMans.

I chose to go with 15 x 7.

They are similar to the 14" rims that have been on the car for the past 15 years or so.

Next week I will be getting the tires mounted.

[Stuart]

You can't go wrong with a set of Torq-Thrusts.

[The Champ]

I believe those Torque Thrusts have only 3.75" BS - if so - you will want to be conservative on your tires sizes. Factory 15x7's plain steel rims had 4.25" BS, so you'll be sticking out an extra .5" with the Torque Thrusts.

Something like a 215/70/15 would give you close to the original tire diameter (27") and should clear front and rear. Your results may vary.

[HALFWAY]

Originally Posted by The Champ

I believe those Torque Thrusts have only 3.75" BS - if so - you will want to be conservative on your tires sizes. Factory 15x7's plain steel rims had 4.25" BS, so you'll be sticking out an extra .5" with the Torque Thrusts.

Something like a 215/70/15 would give you close to the original tire diameter (27") and should clear front and rear. Your results may vary.

I was going to try that size, if not 215/70/15 then 205/70/15.

[HALFWAY]

Question for the lugnut lengths.

The rims I currently have on the car I had to use two washers for the front while the back rims, 1 washer was needed.

I never had any issues using two washers on the front but would prefer only one.

[HALFWAY]

Update, took off one the lugnuts to check if it will fit on the Torque Thrust rims.

No go on the ones I have.

The diameter of the lugnuts is too large.

Plus the TTs have a beveled hole while the old ones do not.

I need a new set, any suggestions?

[64speed]

I have 18x8 with 245/45/18 on all four corners I will have to look up the backspacing. I could go wider on the back

[HALFWAY]

I found the lugnuts I need.

Thanks for the help.

[HALFWAY]

Originally Posted by The Champ

I believe those Torque Thrusts have only 3.75" BS - if so - you will want to be conservative on your tires sizes. Factory 15x7's plain steel rims had 4.25" BS, so you'll be sticking out an extra .5" with the Torque Thrusts.

Something like a 215/70/15 would give you close to the original tire diameter (27") and should clear front and rear. Your results may vary.

I measured the back spacing on the old rims and they are 3.5".

I currently have 205/70/14 tires with no issues so I might be able to get 225/70/15 on these new 15x7 rims with 3.75" back spacing.

[389]

For A bodys I like the 15 x 7 with the 225/70r15. If you want better handling change the front and rear control arms to spherical/delrin bushings and tall ball joints. SC&C has probably the best set going with there SPV arms and Howe bushings. Spohn has some of the best rear adjustable rear control arms with there heavy duty Del Sphere bushings.. Put that suspension on your A body and a set of Coopers will stick like glue. I speak from experience..

The best riding and handling wheels I ever tried were Wheel Vintiques Series 62 and 64 in 15 x7 with 4.25 back space.. No flexing like the aluminum wheels.. The chrome Series 64 look so vintage and cool...

[The Champ]

Originally Posted by HALFWAY

I measured the back spacing on the old rims and they are 3.5".

I currently have 205/70/14 tires with no issues so I might be able to get 225/70/15 on these new 15x7 rims with 3.75" back spacing.

Your 14's are most likely 6" wide rims - so to put the tire in the same spot would require 4" BS on a 7" wide rim.

So..... How much clearance to you have with your existing 205/70's on your car right now?

Remember - your 205/70/14's are only 25.4" tall and the 225/70'/15s are 27.4" tall, so the tires are going to sit 1" higher in the wheelwell.

Section width (bulge of the tire) is 8.2 vs 9" and the tread width is 6.2 vs 6.9".

[HALFWAY]

Originally Posted by The Champ

Your 14's are most likely 6" wide rims - so to put the tire in the same spot would require 4" BS on a 7" wide rim.

"I still have the tires on the 14" rims but a rough measurement looks to be 7"."

So..... How much clearance to you have with your existing 205/70's on your car right now?

"The top of the tire to inner fender is around 4" at the closest point."

Remember - your 205/70/14's are only 25.4" tall and the 225/70'/15s are 27.4" tall, so the tires are going to sit 1" higher in the wheelwells.

"The current tire is 25.5" tall."

Section width (bulge of the tire) is 8.2 vs 9" and the tread width is 6.2 vs 6.9".

Answers to some of your questions in your quote


The "bulge" is close to 9", the tread width is 7".

Should I maybe go with a 60 series?

Sorry, I am not very knowledgeable about tire sizes.

[HALFWAY]

I was thinking about these.

What do you think?

https://tiresize.com/tires/Cooper/CS...-225-60R15.htm

[The Champ]

Halfway

To get a 60 series tall enough you'll end up getting much wider.

I made a mistake when I used the 225/70/15 specs above as 389 mentioned that size in his post.

We had previously discussed the 215/70/15 tire size which is 26.9" tall with a section width of 8.7 and tread width of 6.5. Narrower alternatives that are close in height would be a 195/75/15 or a 205/70/15.

Like I posted earlier, you need to be careful with your tire sizes because of the limited BS of your chosen rims.

This is a link to information that may help you understand tire sizing:

https://www.tirerack.com/tires/tiret...e.jsp?techid=7

For a given tire width - say a 215 - as the series number get smaller (75 - 70 - 60 - 50 - etc) the tire gets shorter. To get back to the same diameter on a 60 vs a 70 series, you need to go to a wider width - in the case of about a 27" tall tire like the 215/70 - that would be a 255/60/15.

[HALFWAY]

Okay, thanks.

I may return these rims for a different back spacing.

Since I have been running shorter tires, is there any adverse effects in doing so?

[The Champ]

Running shorter skinny tires makes it easier to do burnouts because it gives you a lower (numerically higher) effective rear end gear ratio....

On the downside, it also means that your speedometer reads fast and your running more RPM's to get to highway speeds. This means your engine is working harder to maintain highway speeds. This also adversely affects your fuel mileage - but we don't drive these cars for fuel mileage, do we...

Putting the numbers into perspective - with your current tires and assuming you have 3.23 gears (most common):

25.4" tires with a 3.23 rear gear at 70 MPH = 3000 RPM's

OE tire diameter was 27", all other data the same = 2800 RPM's.

Some people like to run the same size tires front and rear. In 1994 I ran 205/75/15's whitewalls (26.1" tall) (I was given the tires and factory rims by a fellow GTO'er that had bought Hurst rims and had no place to store them) before I found a set of Uniroyal 215/65/15 redline radials (26.1") in 1995 - Uniroyal wasn't making them anymore. Years later, when reproduction redline radials became available I went to staggered sizing - 235/60/15 front (26.1) and 255/60/15 (27.1) rear. I now run 17's with 215/55/17's in front (26.3) and 245/50/17's in the rear (26.6).

If you like those rims, you can find tires that will work with them. You just have to stick with a more conservative size. It's your car - go for the look you want. If you want to run wider tires - than a switch to a different rim makes sense.