Tire and wheel choices.

[oldchevyguy]

Hi guys! My car came with older corvette 16 inch wheels with 225 rubber. What is everyone using? 18/19's ? Will 345 30 19's fit in the rear? I need information including offset or backspacing, etc. Thanks, Bill

[oldchevyguy]

42 people read this and no one replied?

[GoDadGo]

My suggestion is to send a private message to" "The Stig"
He'd know for sure.

[Jim Haar]

Bill, 345/35/19's will fit fine, I bought my rims from FFR and don't remember the offset etc.
They would tell you i'm sure.

[Cattrax]

Bill,
I bought a rolling basket (*******) case with wheels and tires. I will go get you what it has. The rear does have spacers (1"+-) that I am not fond of but they may have come with the kit, don't know. Regardless, you can adjust the back spacing if you do not have the spacers. Give me a few minutes to pull the wheels (Corvette) and measure the backspacing.
Ken (Another old Chevy guy. My current track car is an Austin Healey Kit with a 383, I just could not do the Cobra with a Chevy. Also I just sole my Crown V-8 Vair. I bleed orange.)
From my notes, Front 245/40-18 Rear 295/30-19
Ken

[Cattrax]

Bill,
Fronts appear to be about 8 1/2" wide with 6 1/2" backspacing. That calculates out to 2 1/4" offset. My guess is a 55mm offset since many seem to be metric these days.
Rears are about 10" with 8" backspacing. Thus 3" offset. That would be about 75mm.
As noted above, they are Corvette wheels that appear to match. You can probably find a database of Vette wheels to match up and get the exact dimensions.
I think you can fit larger with more of the wheel/tire to the inside. I think mine look pretty good as far as alignment with the fenders go but they could be a bit wider on the outside depending on your taste.
When I was building the Austin Healey, I just took a piece of perforated angle iron and bolted it to the hub. I then cut a piece of wood the width of the tire I wanted to run (245's), beveling the corners a bit, and then I bolted it to the angle iron at half the diameter of the tire (Tirerack has all tire dimensions) and rotated and turned the wheel, adjusting the board location in and out until I was satisfied of the best offset. It takes a little time but it works.
Ken

[RumRunner]

Also purchased my rims from FFR. Tire sizes 245/40-18 up front on 18x9 rims, 335/30-18 in the rear on 18x12 rims. Sorry don't know the offset.

-Michael

[The Stig]

Hi guys! My car came with older corvette 16 inch wheels with 225 rubber. What is everyone using? 18/19's ? Will 345 30 19's fit in the rear? I need information including offset or backspacing, etc. Thanks, Bill

Hello,

I have the offsets that CCW used with my wheels.

I'll have to look through my files on my computer. (I'm in Cleveland this week).

I'll post it as soon as I have a chance.

Mike

[VRaptor SpeedWorks, LLC]

As Michael posted above, the FFR option wheels are 18" all around. FFR has the offsets listed on their website in their parts catalog where the wheels are listed. Those wheels do not use the wheel spacers provided with the kit....they bolt up direct to the hub.

I think you'd be pushing it with 19" 345's.....

[crash]

My suggestion is to contact John at CCW. He knows the GTM well and can get you what you need...no spacers required.

[oldchevyguy]

What is CCW?

[Blast3r0]

What is CCW?

Complete Custom Wheel
http://www.weldwheels.com/ccwheel/

[mlkwd1]

I have the Factory five 18s. 335/30s on the rear and 285/35s on the front. Toyo Proxess 888s. The combination is perfect. Be cautious with running tires this wide on the front. You have to trim the inner hood a little and body area where they have a thick molded section. Not a big deal and should be done before paint. Not a big deal to manage and the 285s definitely helped with a small amount of push with the huge rear tires and a very tight limited slip differential. The front grabs pretty good and you can manage any understeer with the throttle.

Spacer is not required with the FF wheels.

[Drdw]

Mine has Forgestar wheels
Info from factory five
Set Part Number: 26111
Front Wheel Size (Diameter x width): 18"x 9"
Rear Wheel Size (Diameter x width): 18"x 12"
Front Wheel Backspace: 6.95" (50mm Offset)
Rear Wheel Backspace: 8.49" (51mm Offset)
Wheel Lug Pattern: GM style 5 lug x 4.75" bolt circle
Material: Flow formed AluminumColor: Titanium
Tires Michelin Pilot Sports 335/30/18 rear 245/40/18

[oldchevyguy]

Thanks very much for the information guys!