factory tire pressure on the hatch and coupe thu 89-93 was 29 psi with H rated tires.
i’m pretty sure the Car manufacturer recommends a tire pressure that makes sense for the vehicle weight.
If you have a light 240sx and inflate to 29 Psi the tire is going to have optimal pressure, but if you inflate to 40psi you’ve now over-inflated the tire for the car weight. It won’t flatten enough because of the lack of weight and the tire will wear more in the center because its not making even contact.
This is my theory on tire pressures.
the tire placard only applies to the specific tire that CAME on that car O.E.M
anything after wards should be inflated to the tire manufacturers specifications.
even though. tire pressures vary between everyone. it all comes down to the (cold) part of the psi. i’m no tire boy per say. but have been in the trade for 10 years now. and i know that everyone has different “tastes for pressure” as we say at work. yet generally. 2-3 pounds under the maximum pressure at i believe 14 degrees is proper. at least that’s what i was taught. so far. so good. never had a tire come in that i have installed with any concave of any sort.
and xsnrge…alignment. has A LOT to do with braking. sure sasha will tell you that.
that’s my 0.02
wow. way more posts then i expected to be in here…
is around 1psi in difference every 10 deg c up or down…
atleast thats the general number i’ve learn at school
yeah… shouldn’t the tire pressure be based on the actual tire itself? The tire will usually indicate what the max pressure you can put into it.
Ok to clear up some stuff on this thread.
The factory recommended tire pressure is only good if you are running stock rims and the correct factory equipped tires for those stock rims.
A wider then stock tire on a factory rim inflated at a high pressure will cause you to ride on the center of the tire therefore wearing out the center of the tire before the rest. Running too low of a pressure will wear out the inside and outside of the tire before the center. Ok i hope that makes sense.
Now the load rating of a tire detrmines the side wall strength on a correct rim width and only when the tire is at it’s recomended pressure.
Simply put you probably don’t have the original tires that came on the car and quite possibly might not be the original size. Remember all manufactures tires actually measure slightly different for an example a Dunlop vs a Hankook maybe 0.5 smaller diameter and 0.2 wider. Catch my drift?
Therefore duckJAI is correct when stating somewhere around 30-35psi when cold should be sufficiant enough for a DD with close to stock size tires.
How about winter tires?
Same thing?
Anywhere around 30-35psi?
Or again, its all dependant on the tire right?
winters are the same. the only diff with winter tires is the tred.
but as everyone should know, in the winter is the time when you should check your tires the most. usually a huge change in temp all the time
^^ Thanks for clearing that up Adrian
I would use common logic and say to slightly over-inflate a winter tire because it’ll in essence, make the tire thinner, therefore helping to cut through deep snow and slush.
when you over-inflate a tire, it wears down the center more since it “balloons” the tire.
remember, i said SLIGHTLY over-inflate.
So if you’re usually running 32-35psi, run maybe 38ish.
that’s my theory