DMX -- I'm Planning to SUE Over AZ Speeding Arrest

DMX claims Arizona police had NO RIGHT hauling him into jail yesterday -- insisting there is NO POSSIBLE WAY he was driving more than 100 miles per hour ... and now he's ready to sue the cops!

X -- who was allegedly going 102 mph in a 65 zone -- tells TMZ, "I was going 85 miles per hour ... I know for a fact I didn't go more than 90."

X adds, "I'm used to driving fast, I'm a New Yorker ... but I constantly look at the speedometer when I'm driving ... I need to make sure I don't drive too fast."

The rapper says he knows he was technically speeding, but he feels the cops abused their authority by putting him behind bars ... even though his rap sheet takes longer to read than "War and Peace."

"I plan on suing ... and I plan on suing for harassment," DMX says ... adding, "I'm in discussions with multiple lawyers who are not afraid to go against the system in helping me clear my name because I have been harassed."