Blackjack

iTrader: (3)

Just curious to what tire pressure specs everyone is running with 20s. My pressure was low yesterday so I put in oem 35lbs. Should we run higher with 20s?

MaxToTheG37

iTrader: (3)

245/40/19s and 275/35/19s pressure also???

EZDozzit

iTrader: (4)

Yeah I'd like to know too.

TomG37

+1 I would also like to know

g37rider

iTrader: (4)

I have the same wheels/tires you have, and I set mine to 35. Sharif had set them to 34 before shipping.

oOmikeyboy

iTrader: (3)

I assume it would be a about 5-7psi below max (when the tires are cold)? I think on stock people are usually at 35-40, and max reccomended psi is like 45?

IP37

put mine at 37

silent06

Auto manufacturers designate a specifc tire pressure to provide performance/handling characteristics under a certain vehicle load at a maxium top speed. So, the tire pressure psi should only need to be changed, if there is a significant change in vehicle load or top end horsepower/torque.

Below are links to charts at Tire Rack illustrating the adjustments as vehicle conditions change:

http://www.tirerack.com/tires/tirete...adj_Wspeed.jsp

http://www.tirerack.com/tires/tirete...adj_Yspeed.jsp

http://www.tirerack.com/tires/tirete...adj_Zspeed.jsp

http://www.tirerack.com/tires/tirete....jsp?techid=72

silent06

Here is an excerpt from a Bridgestone article outlining requisites to ensure proper tire inflation, when plus sizing:

The concept of plus sizing is not new, but has expanded in the marketplace beyond high performance sports cars. It is important to remember the following:
Always refer to and follow the vehicle manufacturer's replacement tire recommendations.

In some cases, a vehicle manufacturer may specifically advise against the application of replacement tires that are not the original size or type. Always refer to and follow these recommendations.

• Plus sizing typically aids handling performance, but may result in a less comfortable ride; the substitute tires - and their wheels - may also be more susceptible to damage by impact with potholes, road hazards, and other objects such as curbs.

• Never select a tire with a smaller size, or with less load carrying capacity, than the tire specified on the vehicle tire placard.

• Substitute tires should never be inflated below the pressure shown on the vehicle tire placard.

• Never exceed the maximum load capacity and/or inflation pressure listed on the sidewall of the tire.

• Never exceed the maximum load capacity and/or inflation pressure of the wheel.

• Never utilize an unapproved wheel or one that does not meet the approved rim width range for the selected tire size.

• The overall diameter of replacement tires should be within vehicle manufacturer tolerances. If tolerances are not provided, use a guideline of +/-3% from the overall tire diameter of the tire specified on the vehicle tire placard.

• Acceptable load capacity and/or overall tire diameter do not imply acceptable vehicle clearance. Body and chassis clearance must be checked on the vehicle's front and rear axles.

Here is a link to the article by Bridgestone:

http://www.tiresafety.com/images/Tir...ent Manual.pdf


Here is a link to an additional article published by Toyo that provides the Standard Load Inflation table under the ISO Metric (ETRTO) standard.

http://marktg.toyotires.com/file/loadinflationtable.pdf


This table will allow you to determine the OEM load capacity by cross referencing the tire's Load Index by its Inflation Pressure (psi). Once you have determined the OEM load capacity, you can use this chart to ensure your replacement tire meets or exceeds the OEM load capacity by cross referencing the replacement tire's Load Index at a given Inflation Pressure.

Example: The front OEM (225/45/19) load index is 92 and at 35psi has a load capacity of 1345. The typical Toyo replacement (245/35/20 REINFORCED) load index is 95 and at 35psi has a load capacity of 1312. So, the replacement tire needs and requires the inflation pressure to be increased to 36psi, which has a load capacity of 1356. Remember, never lower the inflation pressure below the OEM recommended cold inflation pressure on the tire information placard.


Additional Info:

Tips on Wheel Torquing

• Always, always, always use a quality, calibrated ratchet-style torque wrench to install a wheel. And make sure to torque each fastener to only the specified torque. Air guns and uncontrollable, and can easily over-torque a fastener.

• Treat each wheel as though you paid for it out of your pocket.

• Always allow wheels to cool to room temperature before loosening or tightening the fasteners. And never try to remove a custom wheel while it’s still hot. This will help prevent warping or other damage.

• Tighten fasteners in the proper sequence. Tightening fasteners in a sequential or random pattern can cause warping or cracking.

• Properly support the tire and wheel assembly when torquing fasteners, particularly when you’re working with lug-centric wheels.

• Make sure to use the right socket size. Using an incorrect size socket can damage the fastener edges or scrape the finish.

• When faced with recessed nuts, never use a thick walled socket. These could jam into the nut pocket causing damage, and they can also scrape the wheel’s finish.

• Make sure to handle fasteners carefully. Don’t drop them, and don't bang on them. Also, make sure your sockets are clean so they don't mar or scratch the fasteners or wheel.

• While hand-tightening the fasteners – before final torquing with a torque wrench – carefully rock the wheel to make sure each fastener is centered properly

• Never hand-tighten wheel fasteners then lower the vehicle to the ground before final torquing. Always final torque all wheels before lowering the vehicle.

• Make sure the wheel’s centerline matches the centerline of the hub. If they do not – especially with lug-centric wheels – get another set of wheels that do match properly.

• Never try to get to the full torque measurement at one time. Work gradually up to the final torque to distribute the fastener torque evenly, and avoiding wheel warping or cracking. Go bolt-by-bolt in the prescribed sequence, increasing torque in increments of 20 to 25 percent with each pass. Example: If the final spec is 80 foot-pounds, on the first time through the sequence, torque each fastener to 20 ft. lbs., to 40 ft. lbs. on the second pass, to 60 ft. lbs. on the third, and reach the final 80 ft. lbs. with the fourth pass.

• It is a good idea to retorque each wheel to spec after the first 100 miles of use. This helps assure the wheel is properly seated and fastened, and will help overcome any bolt or fastener stretching that may have occurred

cartronics

im running 20's and from what i remember the wheel shop telling me...i put 35 in the front and between 40-45 in the rear...works fine for me

finagle69

iTrader: (3)

i called Falken Tires to get their take. they asked the full trim of my car (presumably for weight) and told me to set my tires (20") to 37PSI front and rear.

Blackjack

iTrader: (3)

I asked around to a few places as well and was told 36 PSI at most so I believe in the 36-37 range is probably the best way.

NJlakeshoreG

iTrader: (1)

i like to run 34-37 psi in summer and 30-32 lbs in winter...i like to run 5lbs less in winter jsut cuz the summer tires in the cold asphalt....love this set up and i been doin this for years...