I would suggest using 40-45psi all around! I've seen many cracked wheels (esp. cast wheels) because they were running oem press (35 or below) in a 20-22" wheel, with 35 and 40 series tires. Running below 40 psi, you can end up with small hairline cracks and a bent wheel due to impact, and also you can ruin the sidewall of the tires because it's underflated, which means new tires and they don't come cheap in 20's and 22's.. (btw, you cant fix the sidewall of any tire
) Imagine a wheel barrow filled up with sand, and the front tire was at 5psi instead of the normal tire pressure, try pushing it!! It's freakin hard to push and manuevor, in most cases the wheel barrow tire will de-bead itself from the rim.. same thing with car tires..
