MMH2009

Hey guys, Whats the largest size tire I can put on my stock rims? I'm looking at BF Goodrich TA's or Firestone Fire Hawks. Something that's a little bit on the wider side.

Roughrider

I think it's less the biggest size you can fit on the rims but the biggest you can fit without clearance problems. The stock size if F70-15, or the current P-metric size P215/70R15. Chevrolet didn't make fenderwell changes that would officially allow 60 series tires until the '78 model year.

That being said, I think P255/60R15 have worked on many owner's cars but not on others...it seems to be a car by car thing. Some have said going to a P245/60R15 works.

In the front a wider tire can hit when turning...in the rear the trailing arms and parking brake cable brackets are the problem.

Basically all you can do is try different sizes and see if they clear. If they do...you're golden. If not, try a smaller size, modify the trailing ams and/or the brake cable mount or stick with 70 series.

Douglas Mariani

I have P245/60R15's on my 68BB with no rubbing or clearance problems and my friend has them on his 69SB with no rubbing or clearance problems.

7T1vette

From past threads, it seems like 235/60x15's will fit almost all early C3's. Some will take up to 255's. It would be best to check yours for clearances {front, back, inside & outside of each front wheel when turned lock-to-lock} with your present wheels; then compare max tire thicknesses of your tires and all new tire 'candidates' to see what will fit.

coznocoz

Will a P225/70R15 fir my 1969 Corvette?

Thanks

Tom

Calo69

Had 235/70/15 on my stock rims all around, no problems looked good

ts_vette_st

I have 245/60/15 T/A's on factory wheels on my '74 with no issues.

loup68

I have BFG radial T/A's - 245/60/15's all around on my 68 coupe, and would highly recommend them. Lou.

ts_vette_st

245/60/15 also keep speedo close. Speedo reading is with stock 215/70/15 tires actual speed is with 245/60/15.

Speedometer Difference
Speedo Reading Actual Speed
20 mph (32.19 km/h) 19.79 mph (31.86 km/h)
25 mph (40.23 km/h) 24.74 mph (39.82 km/h)
30 mph (48.28 km/h) 29.69 mph (47.78 km/h)
35 mph (56.33 km/h) 34.64 mph (55.75 km/h)
40 mph (64.37 km/h) 39.59 mph (63.71 km/h)
45 mph (72.42 km/h) 44.54 mph (71.68 km/h)
50 mph (80.47 km/h) 49.49 mph (79.64 km/h)
55 mph (88.51 km/h) 54.44 mph (87.61 km/h)
60 mph (96.56 km/h) 59.38 mph (95.57 km/h)
65 mph (104.61 km/h) 64.33 mph (103.53 km/h)

C3s4me

Here is a great link to help you see the difference between tires and wheels.

http://www.rimsntires.com/specspro.jsp

Just plug the stock size in first and then the size you wish to try and it will tell you difference...

I think the stock tire size was an f70 x 15... Todays equivalent would a 215/70/15 rim size is 15 inch rim width 8.0 inches rim backspace is 4 inches or (-13 offset)

By plugging these numbers into the link above it will show you the difference....r