I have 305/30 19s on the rear and 255/35 18s on the front. What tire pressure do you think will be ok. Temp here is around mid 90s.

Thanks

 

Just like it says on the door and in the Owner's Manual:

30 psi cold.

Set pressures with a good hand held gauge - the DIC is for reference when driving only and can't be used for setting/adjusting tire pressures.

Bob

 

I have 30 in them now but I have a dirt ring on the outer wall. Thats why I'm thinking I need to raise it to around 35. It is in the mid 90s so i dont think it would hurt too much

 

I dunno???

All I can tell you is that the recommended cold inflation pressure is 30 psi.

It doesn't matter what the ambient temperatures are, "cold" means before you start driving and build up heat due to flexing of the tires. If it's in the mid 90's now, after the car has been sitting in the garage overnight and there's no elevated temp and pressure due to the tires being heated up from driving, set the pressure to what ever cold inflation pressure you want to go with.

As temps cool off this fall and into the winter, the pressure will go down something like 1 psi for every 10 degree drop in temperature, and you'll need to adjust your cold tire pressure.

As far as the profile of the tire, the OE tires are:
Your tires are sort of between the base and a Z06.

The profiles give less sidewall height on the Z06/GS and the ZR1, and both the Z06/GS and the ZR1 tires all have a recommended cold inflation pressure the same as the base C6 of 30 psi. And that's for all the OE tires that have been put on the car: the Goodyear F1 EMT; the Goodyear F1 Supercar EMT; and the Michelin PS2 ZP.

So....I dunno what to recommend to you. However, if you want to run 35 psi cold that's not going to hurt the tires at all. If you're tracking the car you may well want to increase the cold pressure a little to get hot pressures when you come off the track up to as high as 40-42 psi, but that will depend on the tires you're running.

You may want to experiment around and find what gives you good traction and wear for the tire you're running.

Bob

 

35 psi as a start pressure is too high. All c5 - c6 Corvettes are set to 30 psi. Some folks that track their cars will run 26 to 28 psi before the track event with the mind set that the pressure will increase as the tires heat up. I can tell you from experience running higher than 30 psi will cause uneven wear center to outside edge of the tire.

 

I run 28 cold in my 305/30/19 rears and see even wear.

30 in my 265 fronts.

 

im right at same thing.

what brand of tires do you have? me and floyd are on hankooks differnt brand might need lil more or lil less to get even wear.

one way to tell is do nice lil burnout look at parttenr left behind. see if its light or dark in middle, even, or what. wont help with fronts but will help you dial in rears.

 

I understand that the jamb says 30...my Invos are set at 30 but I seem to be riding too much on the sidewall. The top inch of the sidewall has a dirt ring. That's why I was thinking of increasing the pressure. I don't know if its from cornering too hard or if they are like that running down the road. I'll try and get a pic to show my concern. Perhaps it will be ok running them like that. Guess its more aesthetics to me. I hate scrubbing the dirt off the sidewall everytime I was it. Didn't have that problem with the stockies.

 

I just had my 2011 Coupe re done with nitrogen and they put in 35psi. I guess thats too much.