17" Tire Options?
Heel & Toe
Joined: Oct 2025
Posts: 21
Likes: 14
From: Portland Oregon
If anything the ride quality improves going to a larger diameter wheel. More firm and direct for sure, but it doesn’t have the bouncyness/squirrelyness of 15s. You would have a night and day difference going to a 17” or 18” setup with summer tires and Bilsteins, especially coming from those good looking albeit heavy P02 hubcaps.
Race Director
Joined: Mar 2016
Posts: 14,337
Likes: 8,142
From: Napa Valley California
17” X 8” with 4” back spacing.
They are manufactured by Trans Am Racing and available through Vintage Wheels.
Le Mans Master
Joined: Oct 2007
Posts: 7,445
Likes: 971
From: Tennessee/Rhode Island
If anything the ride quality improves going to a larger diameter wheel. More firm and direct for sure, but it doesn’t have the bouncyness/squirrelyness of 15s. You would have a night and day difference going to a 17” or 18” setup with summer tires and Bilsteins, especially coming from those good looking albeit heavy P02 hubcaps.
Absolutely, Totally true! ^^^^^^^^^
The crap 15 inch tires available in the C3 sizes are, frankly, junk tires.
Yes they are round and black and will roll but in terms of modern tire construction along with ride and performance, they are severely lacking. When I switched 15 years ago from the 255/60/15 BFG Radial TA's T rated (118 mph) to Ultra High Performance Summer Only 255/45/17 W rated, I was stunned at the improved ride quality and, of course, real tire performance versus the antiquated tires from Goodyear/BFG etc....I would never go back to the 15 inch tires currently available. My next move will be possibly 18's.
503Mel, I understand completely the issue of trying to keep it stock which I faced as well with my originally totally stock L-82 4 speed with the gymkhana Sport suspension. I have continuously changed/modified a host of tweaks over the 40 years including the OEM L-82 now a 355 which is a modern version of the L46/L79/LT-1 on Steroids now by a lot, upgraded modern GM C3 suspension with improvements, super efficient modern exhaust, and of course, modern rims allowing modern tire tech. My 78 C3 stills feels like a C3 when I fire her up and drive it, just better all the way around....Hope that helps!
Last edited by jb78L-82; Dec 2, 2025 at 06:46 AM.
Race Director
Joined: Mar 2017
Posts: 11,931
Likes: 4,497
From: Virginia
You won't regret 18" wheels. 18" tires are much better.
If you like the classic look, E-T Mags makes LT-III wheels in 18", with a host of width and backspace options.
https:/www.etmags.com/index.cfm/page/ptype=product/product_id=17/mode=prod/prd17.htm
If you like the classic look, E-T Mags makes LT-III wheels in 18", with a host of width and backspace options.
https:/www.etmags.com/index.cfm/page/ptype=product/product_id=17/mode=prod/prd17.htm
Race Director
Joined: Mar 2016
Posts: 14,337
Likes: 8,142
From: Napa Valley California
They are a beautiful wheel as well.
