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Last month I signed in the forum asking for help on my CMC hitting very hard on the smallest of bumps. One of the suggestions was to run the  front tire inflation to 18psi and the rear tires inflated to 22 psi. My hard hitting speedster is now tame going over bumps. I have been told running the tires at a low psi will create too soft of a sidewall and I am risk of blowing a tire off the rim. I am opening up a discussion regarding the pros and cons of running tires at this psi and am I endangering  myself doing so?

opinions and data will be greatly appreciated.

Renfrance

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@Renfrance asked: "I am opening up a discussion regarding the pros and cons of running tires at this psi (front at 18psi and the rear tires inflated to 22 psi) and am I endangering  myself doing so?"

Well, you're always at risk of thread drift, but that won't necessarily be a danger, per sé.  

For about five years when I first got my car on the road (2001 - 2006) I was running 16 front (205/55/16 tire) and 18 rear (225/55/16 tire) and I thought they rode and handled great and I was a "spirited" driver back then (maybe still!)

THEN, my son and I attended a big deal Porsche weekend at the Watkins Glen road course where we got to drive the old 7.5 mile countryside track as well as the modern road course.  My son was driving and he was pushing well over 70mph, just keeping up with a vintage 911 trying to shake us.  When we hit the first hard corner there was quite a bit of squeeling from the front tires.  He scowled.  At the next hard turn, more squeeling and he turns to me and says:  "You didn't pump up the tires from your usual "Grampa-Soft" level, did'jah?  

I had to admit they were still comfortably soft.  He pressed on, regardless, as the group of 100 Porsches, of all models, led by a NY State Police cruiser, lights flashing, that took off like a Saturn V rocket just daring us all to keep up.  At every squeeling turn (and we hit most of them pretty hard) my son would look over and give me this withering look that just said; "You Dumb-A$$".  I just merrily waved to the spectators on the side of the road.  Never, on any turn, did we feel the tires rolling over onto the sidewalls nor did we feel that it was dangerous - The car is too light for that AND I had 7" wide rims on the rear back then (I now run 6" rims all around).

We eventually made it to the new track and were supposed to form up for a few laps around that track, too, but we detoured and found our way over to the garage area, pulled in and begged someone to pump up the damn tires so he wouldn't be ragging on me anymore.  We brought them up to 24 front and 28 rear and it made a YUGE! difference on all of the track turns in that there was no longer any squeeling AND my son had his huge grin back.  I just merrily waved to the spectators on the side of the track.

Heading back to the hotel we found the ride a bit stiff, so the next morning we dropped them down to 20 front/24 rear just to keep him happy, and when I got home I left them at that pressure ever since because it prevents it from squeeling on the painted pavement lines on a hard left turn onto my street and the lady living on the corner is about 90 these days and I don't want to scare her.  It doesn't ride like a Cadillac, anymore, but it handles a little crisper, like a sports car, and doesn't make any noise.

Hope this helps.

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