What should my tire pressure be with after market rims and tires?

I have a vw golf and just replaced the stock wheels (15") with 18" alloys and lower profile tires, how can i find out what tire pressure i need to have in them? As obviously the factory recommended tire pressure relates to the stock wheels?|||The tire pressure doesn't count on the vehicle weight, it's the tire load index. At stock rim, the pressure is about 33 to 38 Psi. For 18" rim, same pressure can be done, but it won't protect the rim when the pressure is lost or hit a rough road even a hole at road. Add the pressure for about 40 Psi, it will be feel hard, but will protect the rim on bad road or less pressure. Never use pressure over the tire manufacture recommendation as wrote on the side wall.|||your tire pressure is in no way related to the maximum rating of the tire itself and is is directly corresponding to weight distribution of the car itself .. over inflated and your going to wear the inner tread of the tire before your wear the outer and under inflate the opposite you wear the outer edges of the tire but not the inner .. if i remember correct your golf should be 32 psi front and back with the spare being 60 psi .. and this tire pressure does not chance with the size (height) of the tire and rim nor does it chance with the wall height or tire base again the pressure is based on the weight distribution of the car on the tires .. you can confirm the 32 psi rating by either looking on the inside door trim on the driver side on the sticker .. or sometimes located on the sticker in the glove box but usally it is in the driver door trim or door itself|||i think its like 25 lbs . and you can have hydrogen put in them to help prevent swelling . seriously your going to regret those bling bling tires . they may look good but need to be checked often . and if one goes out you will have to replace 2 . if you dont the other 3 will eat up the new tire . i use to watch racing and would think those would be so cool on street cars . then after they came out i realised how usless they are on normal roads .|||Best tire pressure is 35 for ur rims. I also have 18 inch rims with low pro tires. But since u have low pro tires ur ride will be rough. Check ur tire pressure alot cause when u have low pro tires u dont want one of the wheels to have less air cause u will bend ur rims easier|||If your maximum Cold tire pressure is 51PSI then i would set all 4 tires to 40PSI. You can find the maximum cold tire pressure on the sidewall of the tire.|||The tire pressure is marked on the tires themselves - inflate to within 5 psi of the maximum pressure|||low profile tires should be reading about 30 lbs pump pressue|||PSI is PSI. Same as stock. Wow... 18" rims on a golf would look pretty horrible plus make it drive like crap.|||Ask the guys who mounted the tires.....................|||100psi