Tire size help!
Thread Starter
Pro
Joined: Nov 2005
Posts: 655
Likes: 0
From: Virginia
Tire size help!
Alright I am thinking of getting some 18x12's for the back and some 18x9.5's in the front will that be big enough for the front while going that big in the back? If so, I want to get some BFG g-force T/A Drag Radials and they dont come in 335's but 345's......will those fit without rubbing?..........I know I will have to remove the brake ducts though. What BFG's should I use for the fronts that will match the tread style for the back or just which ones will look good with the drag radials in the back?
Drifting
Joined: Oct 2002
Posts: 1,710
Likes: 0
From: Langhorne PA
Originally Posted by wamara
I THINK that unless you have the tire sticking way out past the fender, you would need to tub to run 345's in the rear. Good luck.
Don't think that the 12's will clear either, depending on the offset.
Race Director
Joined: Jul 2005
Posts: 11,308
Likes: 1
From: The Beautiful Greater Bay Area California
345mm wide tire will fit beautifully on an 12 inch wide rear wheel. However, to properly accomodate this extra widened wheel width without having the wheel and tire protrude well beyond the edge of the rear fenderwell (as seen in common HOW offset repro wheels), you really need to "tub" the vehicle.
However, if you are so inclined (again, based on a custom positive C5 offset), you can modify the rear fenders, OR actually replace them completely. And, along that vein, ACP does offer a small 3/4 of an inch extra extended rear C5 replacement fender kit to help clear 335's, and, barely the 345's without tubbing.
The critical factor here will always be what custom wheel offset measurement you specifically choose to best accomodate your specific application needs. Call HRE Wheels in SoCal for an in depth and enlightening conversation regarding wheel offsets to better acquaint you with the realm of wider wheel and tire fitment. Frankly, this is an expensive, but, fantastic upgrade.
However, if you are so inclined (again, based on a custom positive C5 offset), you can modify the rear fenders, OR actually replace them completely. And, along that vein, ACP does offer a small 3/4 of an inch extra extended rear C5 replacement fender kit to help clear 335's, and, barely the 345's without tubbing.
The critical factor here will always be what custom wheel offset measurement you specifically choose to best accomodate your specific application needs. Call HRE Wheels in SoCal for an in depth and enlightening conversation regarding wheel offsets to better acquaint you with the realm of wider wheel and tire fitment. Frankly, this is an expensive, but, fantastic upgrade.
Race Director
Joined: Jan 2002
Posts: 19,557
Likes: 1,470
From: I love you & miss you Linda
2017 C7 of the Year Finalist
St. Jude Contributor
First, here is something that may interest you. You may know all this, but in case not. It's always good to understand offsets, especially when you are thinking about putting 12" wheels on your car with those HUGE 345's...
NOW, how about using an 18x11" wheel and the BFG 315/35x18 Drag Radial and match them with BFG KDW 265/35x18's on your front 18x9.5" wheels.
NOW, how about using an 18x11" wheel and the BFG 315/35x18 Drag Radial and match them with BFG KDW 265/35x18's on your front 18x9.5" wheels.
Race Director
Joined: Jul 2005
Posts: 11,308
Likes: 1
From: The Beautiful Greater Bay Area California
Originally Posted by Glennm27
First, here is something that may interest you. You may know all this, but in case not. It's always good to understand offsets, especially when you are thinking about putting 12" wheels on your car with those HUGE 345's...
NOW, how about using an 18x11" wheel and the BFG 315/35x18 Drag Radial and match them with BFG KDW 265/35x18's on your front 18x9.5" wheels.
NOW, how about using an 18x11" wheel and the BFG 315/35x18 Drag Radial and match them with BFG KDW 265/35x18's on your front 18x9.5" wheels.
(Hi Glenn! 
) Now, this is an excellent upgrade that will not force you to modify the body, fenders, cargo area, nor, even fenderwells with the proper o.e. C5 offset to accomodate this specific wheel sizing. In fact, this particular wheel sizing has been a common Corvette upgrade since the introduction of the C4 ZR1 which had 275mm tires mounted on 17X9.5 fronts, coupled wth 315mm tires on 17X11 inch rears. Again, tire sizing, and, availability of matching models for BOTH axles will always be the deciding factor. As many of you have already discovered, not all sizes and models are offered by all tire manufacturers.
Race Director
Joined: Jan 2002
Posts: 19,557
Likes: 1,470
From: I love you & miss you Linda
2017 C7 of the Year Finalist
St. Jude Contributor
Originally Posted by Glennm27
NOW, how about using an 18x11" wheel and the BFG 315/35x18 Drag Radial and match them with BFG KDW 265/35x18's on your front 18x9.5" wheels.
Check the links below..
BF Goodrich g-Force T/A Drag Radial
BF Goodrich g-Force T/A KDW
Hi edensknight
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Race Director
Joined: Jul 2005
Posts: 11,308
Likes: 1
From: The Beautiful Greater Bay Area California
Those tire sizes sure are, Glenn. And, that set up has been one of my all time favorite wheel and tire combos as an tire and wheel upgrade for the C5 since its introduction. Frankly, I had this great set up for several years previous to my current 13's with Pirelli PZero Rosso Assimetrico's. 
And, that set up has been one of my all time favorite wheel and tire combos as an tire and wheel upgrade for the C5 since its introduction. Frankly, I had this great set up for several years previous to my current 13's with Pirelli PZero Rosso Assimetrico's.
Team Owner
Joined: Jul 2004
Posts: 24,652
Likes: 298
From: NJ
St. Jude Donor '05-'08
Originally Posted by C6this
So will a 18x12 with a 64 offset fit in the back with 345's? I mean I dont care if they stick out a little past the fender what is the big deal with that?
the big deal is that they will rub the fender and thus could crack it.
I would not go with that size tire without tubbing the car. I just bought CCWs 18x10 fronts and 18x11.5 rears. I can fit a nice size 315 tire on the rear without tubbing.
Why are you looking for a wider tire that might help with some answers.
Race Director
Joined: Jul 2005
Posts: 11,308
Likes: 1
From: The Beautiful Greater Bay Area California
Hello, C6this,
Greetings, to you. I just now, happened to see your latest query. And, yes, you will need to "tub" the vehicle in order to accommodate 18X12, or, 19X12 inch rear wheels with an wheel offset based upon an common "positive offset" C5 application. Moreover, you will also need a 74mm positive offset which is a traditional positive offset standard (as commonly applied to the Corvette C5 with HRE Wheels in 12 inch rear wheel width's).
In fact, there are other positive offset measurements that can be utilized beyond the 74mm application. However, the 74mm positive offset is an important, and, common standard as mentioned above. And, again a 345mm width tire size is perfect on an 12 inch wide wheel. Please do feel free to PM me with any futher questions, and, I would be more than happy to offer you further assistance. Best wishes to you.
Greetings, to you. I just now, happened to see your latest query. And, yes, you will need to "tub" the vehicle in order to accommodate 18X12, or, 19X12 inch rear wheels with an wheel offset based upon an common "positive offset" C5 application. Moreover, you will also need a 74mm positive offset which is a traditional positive offset standard (as commonly applied to the Corvette C5 with HRE Wheels in 12 inch rear wheel width's).
In fact, there are other positive offset measurements that can be utilized beyond the 74mm application. However, the 74mm positive offset is an important, and, common standard as mentioned above. And, again a 345mm width tire size is perfect on an 12 inch wide wheel. Please do feel free to PM me with any futher questions, and, I would be more than happy to offer you further assistance. Best wishes to you.