I recently removed an aftermarket coilover suspension system from Cross and replaced the original OEM suspension components. Nothing wrong with the Cross stuff, just didn't like the ride. But there was no objectionable grind felt in the steering wheel.


So with the original suspension at the Porsche recommended tire pressure of 36 and 44, it still rides like a truck. The rebound is dampened fine and there is no bounce. But road ripples come through to the steering wheel in a more annoying way than the Cross kit. Kind of a grind in the steering wheel.


The original suspension only had about 10k miles and visually they looked perfect. So I don't think there is a problem with them.


I reduced the pressures to 32 and 40 and it is better but still pretty rough.


Porsche says 32 and 40 is probably fine but would not drop it any further. These are the correct OEM tires for the car.


Does anyone have any data or opinion on how far I can drop the pressures to ?? Can I run them at 30 and 38? Even lower? I am not tracking the car. This is for around town only.


Thanks for any thoughts on this.

I wouldnt go any lower then that ,especially on the street..Mushy feel and more prone to dented rims..
Now at the drag strip is a different story..lol
That's why I went to larger diameter tires for a better ride and a bit more clearance on the street, plus it makes my oil changes easier..

32 and 40 is what I run as well. I think 30 and 38 is about as low as I would go. I think the stock 36/44 is too high and may be the directive when driving at high speeds for long periods of time. At that pressure, the rear tires were wearing in the middle, which tells me it is too high.

Low pressure isn't bad but you will get some sidewall flex and the tires will heat up more. None of which will be a problem driving around town (except for big pot holes then ).

Just as a side, I would agree that the stock suspension is pretty harsh. My BMW is lower on H&R coilovers but has a much better ride. Coilovers are really the only way to dial it in perfectly.

I didn't believe it BUT when I take long road trips on the highway I have noticed that having it 4psi lower, cold, then called for does effect mileage from the 36/44 pressure.

I do 35/36; this setting is ideal (to me) to run on windy roads.

Makes sense. I actually always check that the pressure is up to spec on our SUV when taking long road trips. It's already a gas guzzler as it is, so may as well save a few $$ by taking 2 min to check the tire pressure

Thanks for the feedback everyone. Confirms what I have been able to figure out through seat of the pants measuring!


I do agree that the lower pressures will decrease miles per gallon.


I think I will experiment by dropping another 2 psi. But I suspect that I will end up in the long run just staying where I am now at 32/40.

I run 31 front and 32 rear cold
This puts me at 35 front and 36 rear when hot

Better overall with these pressures, much less tramlining and better stability at speed. I run JIC Cross suspension, no issues with weird steering wheel feedback.