Gymkata

Thanks for the comments. I've never had an issue running 36psi except for one gouge on one of the wheels when my wife pinched the sidewall entering a driveway too fast. I imagine running a higher psi will help avoid pothole flats a little, but I don't want to lose grip.

BTW, if I tried the 90% rule with my truck tires, I would be running 72psi!!! As it is right now they are at 42psi and don't bulge at all with 2000 lbs in the bed...they are Kevlar lined though and have much stiffer sidewalls that the stock tires.

LexusISF19

I run 35 psi all around still curious to see what others use

v8sten

iTrader: (1)

I run 33 psi hot all the way around, I found in the owners manual that you can set the pressure on the TPMS, Im not sure what page but it is in there and I did set mine. With it being almost midnight im not gunna go out to my car to find out for sure, but i do know the info needed to reset the TPMS is in there.

PinkBear

I also run 35 psi on all 4. No problems!

lobuxracer

iTrader: (2)

Hot? Like after 10 laps on a road course hot, or just drove awhile on the freeway hot? There is a huge difference.

flowrider

iTrader: (9)

I set mine cold - at 37lbs. for all four corners.

Lou

kdm

The other day, TPMS light went on. Went to the gas station to fill up on air. Realized front right tire was running on around low 20s, which was surprising. All other tires were at 30 psi.

Is this because the IS-F has "pulling to the right" issues?

flowrider

iTrader: (9)

^^^^Sounds like a slow leak If you drive to the gas station for air, you do realize your heating up your tires, right? And you can't get a good cold pressure reading. Better to have a compressor at home and fill them up cold.

Lou

itsmike177

iTrader: (3)

I've played around with air pressures on the PSS (stock size, stock wheels) and 36-37psi cold is a good balance for daily driving and curvy mountain roads. Tried 44 psi cold as well and when the tires get heated from driving, they definitely have less traction upon hard acceleration/cornering.

I would never go below the factory recommended PSI settings on tire pressures while driving on public roads.

On the track, 36 psi cold, after a session, 44psi hot. The PSS' don't last more than 4 laps (2.8mile course, 20-30min sessions) before they lose grip and get greasy. Even after dropping the tire pressure to 36 psi hot, same issue. Due to the weight of the ISF, it really needs r-compound tires for track duty.

In conclusion, everyday driving = 36 psi. Track duty = depends on the track layout and other factors if running stock street tires.

lexuz125th

iTrader: (1)

Had 36 PSI cold, after a few laps it was 48 PSI. People at the track recommend I put it down to 38 PSI when hot. Thoughts? ? Suggestions? ?

lobuxracer

iTrader: (2)

I wouldn't go that low. I aim for 44 psi hot on a road course. It works out to 32 psi cold (air temp around 72F - 22C) the next morning.

v8sten

iTrader: (1)

"Spirited" freeway and "spirited" regular road driving. I did that for comfort mainly. If I were to take it on a road course I would up the pressure