hey guys recently i noticed iv been having a slight "boaty" feeling when corning and spirited driving.
i have fairly new supra lca's and tein ss for a supra and normally i feel very planted to the ground even during the most spirited driving

I am running staggered 19's with 245/30/19 in the front and 275/30 in the back

to start small i checked my tire pressure and noticed my fronts are almost at 40 psi and my rears barely at 30. the max tire pressure says 50 psi

but my QUESTION is whats ideal front/read tire pressures to help with handling? i know this has gotta be throwing me off a bit

 

one way to find out what tire pressures you need for aftermarket rims is to shade a 1/4 of your tires tred with chalk and drive her down the road straight. if the chalk wears more in the middle your tires are over inflated. if the chalk wears more on the sides then there under inflated.

 

I know this is a bit old, but I did some research on my own and wanted to share.

What is the load rating of the tires you're using? Are they reinforced or extra load rated?

Stock load rating is 1334 lbs (94V rating) and by replacing with a different load rated tire, you'll want to make sure your tire pressure is correctly set to carry the optimal load (greater than or equal to stock).

For example, I have "235/40R18 95W XL" in the fronts and "265/35R18 93W" in the rears. If I run 36 psi in the fronts for a load of 1356 lbs and 33 psi in the rears for 1345 lbs. Any less and the load drops below stock, and we get tire role, and crappy handling, and terrible gas mileage.

I hope this makes sense. I can provide the answer if you can answer my questions above.