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-   -   Tire & wheel decisions - 69 Executive (https://forums.maxperformanceinc.com/forums/showthread.php?t=864470)

scottydl 02-03-2023 10:18 PM

Tire & wheel decisions - 69 Executive
 
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I've read all the threads I could find here on tire size options for our Darksiders. For 15" it seems that 235/70, 225/75, and 225/70 are all decent size replacements for the original bias ply sizes.

On my '69 Executive, I've had sporty chrome rims with white letter 235/60R15's, lower profile than factory... nice look but the speedo ran a little high. Then I went back to 1" whitewall 225/75R15's on factory steel wheels and the original PMD hubcaps. I think those more closely matched the factory size.

It's due for tires again, and I'd really love to find some wire spoked chrome wheel on a slightly wider whitewall... more "white" wall, not a wider tire. I realize that's more of a late 50's or early 60's look, but I still think it looks great on any classic cruiser. BUT the wire spokes + spinners I'm looking for (like the pic attached) are hard to find and usually 14" instead of 15".

All that to say -- does it make sense to go from 15" to 14" rims on my '69? I found Suretec Power Cruiser tires for pretty decent prices, but that seems like an off-brand I haven't heard of. But for a car that is rarely driven, that may be okay.

SD455DJ 02-05-2023 11:55 AM

Personally, I'd stick with the 15" wheels where your tire choices are much greater and the larger tire on a B-body looks better too...IMHO.

Dennis

Stuart 02-05-2023 12:11 PM

The biggest 14" tire on that Suretrac website is 205/75 which is really too small for your car, unless you're going for the lowrider look. As far as that goes, 205/75 is pretty much the biggest 14" tire available these days unless you go to a specialist source like Coker or Diamondback.

SD455DJ 02-05-2023 12:31 PM

The biggest (tallest) 14" tire I've found recently (looking for 14" tires for my '69 Lemans) is a 215/75R14 Hankook Kinergy ST H735 tire at 26.6” available through many suppliers (Tire Rack, Walmart, Amazon, Discount Tire, etc.) in WW or BW.

Dennis

scottydl 02-05-2023 12:43 PM

Yeah I don’t really want a smaller wheel… and 25 years ago I would’ve thought a lowrider was cool but I’ve outgrown that. �� But I do want a nice set of wire basket wheels at some point, and the decent used sets I’ve seen always seem to be 14” … along with PMD spinner hubcaps from earlier 60’s models, which I’d also like.

1965gp 02-05-2023 09:53 PM

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You need some swangers!

scottydl 02-05-2023 10:00 PM

Nooooooooooo LOL :D

scottydl 02-07-2023 06:35 PM

Thanks to the Facebook Marketplace algorithm tracking my searches (apparently), I came across a set of 15" wire wheels in good shape less than an hour from my house. A guy is taking them off his Corvette so they have a 4.75 bolt pattern. The other problem is the tire size, 255/60R15... shorter than stock, but obviously much wider than the 225/75R15's currently installed. Is there any chance of making those work?

Stuart 02-07-2023 09:10 PM

You'd have to get the revised wheel bolt pattern redrilled in your rear axles and front hubs.

north 02-08-2023 03:35 PM

Actually the closest modern size for stock tires are 225/75/15 for the standard 8.55/15’s and 235/75/15 for the optional H and J optional tires. The B body cars in 69-70 have very large wheel houses so you really need large diameter tires to not look under wheeled!

scottydl 02-11-2023 11:47 PM

According to a tire size comparison calculator, the 255/60’s are only 1.3” shorter than the “stock” size 225/75’s currently installed. But also 1.1” wider, which sounds small but I’m not sure if that could cause any lateral clearance issues.

Quote:

Originally Posted by Stuart (Post 6406702)
You'd have to get the revised wheel bolt pattern redrilled in your rear axles and front hubs.

Any idea what kind of job this is, for a machine shop (I assume) that does automotive work? My Executive has drum brakes all the way around FWIW.

scottydl 02-13-2023 04:01 PM

And for my own clarification (and because a machine shop will probably ask)... is this Pontiac Classic Bolt Pattern Reference Guide correct? If so, then it appears that my Executive's bolt pattern is 5x127 (5") since it has the 400ci engine... rather than the 5x120.7 (4.75") pattern that many of the other models have. So close!!

Stuart 02-13-2023 04:35 PM

Quote:

Originally Posted by scottydl (Post 6407900)
And for my own clarification (and because a machine shop will probably ask)... is this Pontiac Classic Bolt Pattern Reference Guide correct? If so, then it appears that my Executive's bolt pattern is 5x127 (5") since it has the 400ci engine... rather than the 5x120.7 (4.75") pattern that many of the other models have. So close!!

That guide is not correct. All full size Pontiacs used a 5 x 5" wheel bolt pattern at least back to 1950, up until 1977. In 1977 and later they went to a mix of 4.75" and 5" patterns depending on the options.

b-man 02-13-2023 06:04 PM

It’s not just the smaller bolt pattern.

The 4.75” bolt circle wheels also have a smaller center bore, the front drum hubs and rear axles would need to be turned down to match the new wheels.

I ran into this issue myself when I converted some 1979 12” B-body rotors to 4.75” bolt circle, had to turn down the hubs so the GM intermediate wheels would fit.

Really not worth it in my opinion unless you can get the machine work done cheap or free.

scottydl 02-13-2023 08:19 PM

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Problem is this style of wire wheels + spinners... I just can't find 'em anywhere (in decent shape anyway) and I hate to lose out on these. Pics below. If I could find a good set of 15" with a 5x5 pattern, I'd jump all over that.

If any of you have connections or know anyone selling something like this, please let me know!

b-man 02-13-2023 09:02 PM

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It’s just machine work.

It takes some figuring where to drill your new bolt pattern so you don’t run into obstacles like stiffening ribs inside the front hubs or on the rear axle flanges avoiding those big holes used to access the bearing retainer bolts.

Some examples of what you have to deal with when doing something along these lines pictured below.

The front rotors started out 5 on 112mm and were drilled 5 on 4.75” GM intermediate. Rear drums started out 4 on 130mm and ended up the same as the fronts, 5 on 4.75” (120.65mm). One of the holes had to be plugged on the rear drum because no matter where you tried to place the new 5 bolt pattern one would always interfere with that hole.

All the machine work was done at my workplace in our machine shop as a favor by one of my coworkers, I just had to figure out how to get it the way I needed it to be.

Stuart 02-13-2023 09:04 PM

To be honest wire wheels aren't very fashionable these days outside of the lowrider crowd, so it will probably be hard to find a 15" set on the used market. You could probably get a new set from Truespoke but of course they won't be cheap. https://www.truespoke.com

scottydl 02-13-2023 09:35 PM

Unfortunately I don’t have any buddies with machine shops, and those pics are great (thanks for posting) but it sounds like it was pretty experimental. So I’d want to find a shop that knows what they’re doing with this kind of project. What did you plug the holes with?

Although the lowrider craze from the 90’s is probably what got me started liking wire wheels, that’s not the look I’m going for necessarily and that style of wire wheels (like Daytons) are different than the criss-cross spoke style pictured above. Such a great classic look IMO. Better on a cruiser like mine, than something sporty… for my preference anyway.

b-man 02-13-2023 09:49 PM

I used a lug bolt (older VWs like some modern BMWs use lug bolts not studs) to plug the hole. Red Loctite secured the bolt then I cut the head off the bolt and ground it flush, this way I didn’t have to weld and possibly distort the rear inner hub.

The machinist who helped me on my project back in 1989 asked me what the hell I was doing. I told him to shut up and just do it and he’d see the results later. I have over 50 thousand miles on those 16x8.5” 1984 Corvette wheels so I’d say my experiment was a success. :)

scottydl 02-26-2023 11:31 PM

Striking out on machine shops in my area. I called 4 and only one said it MAYBE was something he could do. But he’d have to see it first. He quoted me $60-90 per wheel, and that was for bolt drilling only and didn’t include the center bore modifications that would also be needed. I don’t think will be a worthwhile expense unfortunately.

I really didn’t imagine this request would be so complex, especially for these shops that routinely work on trailer axles etc. *shrug*


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