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Old 07-02-2021, 10:59 AM
98 SNAKE EATER 98 SNAKE EATER is offline
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Question Largest 18" wheels that will fit without rubbing? (factory height)

Love the look of the factory JW's, but want another set of wheel/tires that I can thrash around with.







I wanna go bigger (Pro-Touring style), but still want the Rally II look


Love the WV/Circle Racing Billets on the Losi T/A and actually prefer them over the Year One Aluminum Rally II's

From what I can tell, I think he's running 19's, but I don't wanna go bigger than 18's









He's also running air suspension, so what fits his may not fit the factory leafs




Question is what are the widest 18's I can fit the factory suspension without cutting or rolling lips?


Contacted Circle Racing and they said the following:

18 x 8's front @ 4-1/2
18 x 9.5's rear @ 5
Possibly 10's in rear @ 5-1/4


Just curious what you guys have been able to stuff under the fenders/quarters without rubbing

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Old 07-02-2021, 12:20 PM
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Your car looks really good............... **as is**

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Old 07-03-2021, 01:16 PM
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The underside of the "Losi" car is just horrid. Gotta wonder how they keep the rear from chucking.
I have seen a bunch that people just lay on the undercoating and say its sound deadener.
Being that it shines, it really looks like a hack job, not saying it is, just an observation.. IMHO..
Ps, the wheels look like magnum 500's from a distance. Too tall for me, but I like the design and chrome.

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Old 07-03-2021, 01:29 PM
98 SNAKE EATER 98 SNAKE EATER is offline
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Quote:
Originally Posted by bird72 View Post
Your car looks really good............... **as is**

I think so too, but I still want another set of wheels/tires I can go race around with.

Quote:
Originally Posted by Formulabruce View Post
Ps, the wheels look like magnum 500's from a distance. Too tall for me, but I like the design and chrome.
Closest I've seen are these VN501's from American Racing


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Old 07-03-2021, 01:41 PM
98 SNAKE EATER 98 SNAKE EATER is offline
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BTW, here's what a set of 17's look like on a 1st Gen for reference (pretty sure I took these at the Power Tour years ago)






Would like to see how they look on a 2nd Gen




I prefer the look of the stepped offset and smaller slots over the Year One wheels with the single dish and huge openings that would only reveal my factory brakes lol



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Old 07-03-2021, 02:13 PM
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Originally Posted by 98 SNAKE EATER View Post
I think so too, but I still want another set of wheels/tires I can go race around with.
I will be curious your take on handling improvement, with that tire change and no other changes. I would expect a bit tighter on the twisties. I am putting a WS6 box in my 72 for a different approach.

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Old 07-03-2021, 02:44 PM
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Quote:
Originally Posted by 98 SNAKE EATER View Post
I think so too, but I still want another set of wheels/tires I can go race around with.



Closest I've seen are these VN501's from American Racing

I can't post a picture from work but here is a link to Restore a Muscle Cars Ebay site. They sell a 17 and 18 inch rally II style wheel that looks good.

https://www.ebay.com/itm/32329215186...QAAOxyuR5Taqib

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Old 07-03-2021, 02:53 PM
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Quote:
Originally Posted by bird72 View Post
I will be curious your take on handling improvement, with that tire change and no other changes.
I don't expect much gain if any, but I'd rather not wear out the factory rubber and save the JWs for shows


Quote:
Originally Posted by jhein View Post
I can't post a picture from work but here is a link to Restore a Muscle Cars Ebay site. They sell a 17 and 18 inch rally II style wheel that looks good.

https://www.ebay.com/itm/32329215186...QAAOxyuR5Taqib
Not a fan of the flat offset and large cutouts

Prefer the stepped offset and smaller cutouts of the Billet wheels as they look more like an oversized JW

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Old 07-03-2021, 03:12 PM
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Handling? What about ride too? Put tires with no sidewall
, designed for a very fast Strut suspension, on a old car, and you have a 3 ton truck. The response of old squeezed rubber and too tight anti sway bars gives you a ride your body, your back, and the ice cream will never like.
I highly recommend at least installing Del~a~Lum bearings in the entire suspension to speed up the response to absorb bumps and keep tires on the ground.

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Old 07-04-2021, 12:51 PM
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I ran a set of 16x8 Torque Thrusts with 4" BS and a 245/50R16 tire on that car for a while. Those wheels are now on my SD455..

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Old 07-04-2021, 03:57 PM
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I bolted on some 18s on my 71 a few years back, so the info is a little fuzzy, but I think they were:

Rears 18×9.5 with a 5" backspace, 275/40R18
Fronts 18×8 with a 4.5" backspace, 245/45R18

They fit pretty good.

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Old 07-04-2021, 04:33 PM
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Same as 72projectbird.

FWIW...CARiD guaranteed that 285s would fit in the rear, but I opted for 275s to be safe with my disc conversion.

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Old 07-05-2021, 03:28 PM
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I like the look of the Trans Am style superlite wheels. I feel its a more classic/racing look


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Old 07-05-2021, 11:36 PM
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Quote:
Originally Posted by 72projectbird View Post
I bolted on some 18s on my 71 a few years back, so the info is a little fuzzy, but I think they were:

Rears 18×9.5 with a 5" backspace, 275/40R18
Fronts 18×8 with a 4.5" backspace, 245/45R18

They fit pretty good.
No rubbing? Those are the sizes I'm planning to get when I order new wheels and tires for my car.

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Old 07-06-2021, 12:30 PM
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Quote:
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No rubbing? Those are the sizes I'm planning to get when I order new wheels and tires for my car.
I only put about 2 miles on the setup, but no rubbing. My car sat kinda high when I had them on. I never got to try them once I changed my springs.

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Old 07-07-2021, 10:11 AM
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Quote:
Originally Posted by 98 SNAKE EATER View Post
I think so too, but I still want another set of wheels/tires I can go race around with.



Closest I've seen are these VN501's from American Racing


There is these too: https://us-mags.com/trans-am-us722-w-5713.htm

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Old 07-08-2021, 12:33 AM
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Quote:
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Doesn't have a stepped offset and the slots are too big



Anyone happen to know the actual size(s) of the wheels on the Losi T/A?


I thought they were 19's, but after zooming in on the tire size, they apear to be 18's (I think)



If that's the case, I'd like to go an inch smaller so I can stuff a little more meat in there and not look like rubber bands

The 17's on the 1st gen posted above look good, but if I go with staggered offsets, I'd like for the rears to stick in rather than out (if that makes any sense)

Like make the wheels wider without making the stepped offset wider

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Old 07-08-2021, 03:05 PM
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Couple things to keep in mind.

With OE width and offset (8" wide, zero offset), you can do a 275 in the rear, and a 255 in the front pretty safely. (as long as you maintain aspect ratios for plus sizing)

Many 2nd gens, the rear is more towards the passenger side, so use the passenger side for calculating/measuring.

The taller a sidewall is, the more 'squirm' you get, and the more squirm you have, the more clearance you need between the tire and contact points.

The 3 contact point in the rear are the fender lip, the leaf spring, and the rear seat belt bulge.

You can roll the fender lips, giving you about an added 1/2" more clearance. To roll the front lips, you need to trim the inner fenderwell from about 10 o'clock to 2 o'clock. (look at the Herb Adams approach for a guide)

Switching to disc brakes on the rear adds about 1/2" per side to the track width. You can compensate by using a wheel that's offset more to the inside, or narrow the rear housing.

With the front lips rolled, and aftermarket upper control arms, you can run 275s. (with 9" wheel width and between 5-6 offset, depending on your suspension)

With all the planets aligned, and correct wheel width and offset, the max size rear tire that clears is in the 295-305 range. On the front, max is about 255-275.

Some wheel manufacturers state wheel widths in whole numbers, some in half numbers, and some in both. Usually, ones that are half number are measured from outside of lip to outside of lip, whole numbers are from bead to bead. You need to ask, and even then, you may not get the correct answer.

The same size tire may be different in widths and/or sidewall bulge from different manufacturers. Look at the specs of the tires you are considering, and compare to others to be safe. Tire Rack lists section width and tread width in the specs for all the tires they carry.

18x8 with zero offset for the front is just about perfect, and 18x9 or 9.5 in the rear. Start with 245s in the front, and 255 or 275s in the rear. See how much room you have, and size your next set closer to YOUR car's max. That's the safest approach.

Both 255s and 275s technically call for a min 9" wheel width, but you can get away with an 8. (You will have more sidewall squirm though, and it adds sidewall width)


.

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Old 07-09-2021, 10:04 AM
98 SNAKE EATER 98 SNAKE EATER is offline
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Quote:
Originally Posted by HWYSTR455 View Post
Couple things to keep in mind.

With OE width and offset (8" wide, zero offset), you can do a 275 in the rear, and a 255 in the front pretty safely. (as long as you maintain aspect ratios for plus sizing)

Many 2nd gens, the rear is more towards the passenger side, so use the passenger side for calculating/measuring.

The taller a sidewall is, the more 'squirm' you get, and the more squirm you have, the more clearance you need between the tire and contact points.

The 3 contact point in the rear are the fender lip, the leaf spring, and the rear seat belt bulge.

You can roll the fender lips, giving you about an added 1/2" more clearance. To roll the front lips, you need to trim the inner fenderwell from about 10 o'clock to 2 o'clock. (look at the Herb Adams approach for a guide)

Switching to disc brakes on the rear adds about 1/2" per side to the track width. You can compensate by using a wheel that's offset more to the inside, or narrow the rear housing.

With the front lips rolled, and aftermarket upper control arms, you can run 275s. (with 9" wheel width and between 5-6 offset, depending on your suspension)

With all the planets aligned, and correct wheel width and offset, the max size rear tire that clears is in the 295-305 range. On the front, max is about 255-275.

Some wheel manufacturers state wheel widths in whole numbers, some in half numbers, and some in both. Usually, ones that are half number are measured from outside of lip to outside of lip, whole numbers are from bead to bead. You need to ask, and even then, you may not get the correct answer.

The same size tire may be different in widths and/or sidewall bulge from different manufacturers. Look at the specs of the tires you are considering, and compare to others to be safe. Tire Rack lists section width and tread width in the specs for all the tires they carry.

18x8 with zero offset for the front is just about perfect, and 18x9 or 9.5 in the rear. Start with 245s in the front, and 255 or 275s in the rear. See how much room you have, and size your next set closer to YOUR car's max. That's the safest approach.

Both 255s and 275s technically call for a min 9" wheel width, but you can get away with an 8. (You will have more sidewall squirm though, and it adds sidewall width)


.

Thanks for all the info

I was actually thinking about having a custom wheel shop take measurements to see what will really fit in there

https://www.youtube.com/watch?v=4cx9apL7HhY&t=583s

https://www.motortrend.com/how-to/fi...-fit-your-car/


CR got back to me with ricing on the 18's

Quote:
18 X 8 Pontiac Rallye II $742.72 each
18 X 9.5 Pontiac Rallye II $757.03 each
Shipping $275.00
ouch

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Old 07-09-2021, 10:48 AM
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Custom billet wheels are not cheap, as you recently found out. You want sticker shock? Price some forged billet wheels. (HRE, Fiske, etc)

Honestly, unless you are building an autocross or other competition car, picking wheels that are offered in 'popular' sizes is a much more affordable solution. You might be cornered into using a size tire that is one or two sizes smaller than the 'max', overall, you can still get acceptable performance out of them.

Using this approach, you should still be able to run a pretty decent size tire, as mentioned before. Also keep in mind, it is possible to go too big. When a tire patch (what is actually making contact to the ground) gets bigger, the corner load is spread over a greater area, and downforce is reduced. Not to mention things like the hydroplaning factor increases.

If your' budget has no bounds, with a DSE hydroformed frame and associated suspension, I have seen 325s on the front of a 2nd gen. Doing the rear Qudralink, you can go to a 355. But if $750 a wheel is mustering an 'ouch', don't bother looking into the DSE top of the line options.

You can have a 'custom' shop do the measurements for you, but it still only gets you close, and it is still dependent on the skill level of the shop. I personally think it's a waste of money, with time and attention, a DYI-er can easily do the measuring.

Also keep in mind once you go over 275, you will need wider wheels, and you already are squealing on the 8s & 9.5s.

You can also go to cruises and shows, look at similar cars and what they are running, to get ideas of what will fit.

Remember too that once you go to shorter sidewall tires, to get the 'correct' look, you will have to lower the car some. That's where all the 'rubber band' comments come from, a poor execution of plus sizing.

True too that once you go to a shorter sidewall, you need to make your suspension articulate freely in order to have proper handling and ride quality. But honestly, you should already have done that anyway, since to OE suspension is fairly ridged.

.

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