On the highway it runs about 140 to 160 and in traffic it runs about 200 to 220.
It has a 160 stat and aftermarket chip.
Is this normal or is there something wrong.

 

my car likes to do that too, when cruising down the highway it likes to stay at what APPEARS to be 140*, but i've been told several times that the stock temp guage is nowhere near accurate enough and the temp is actually much higher than what it appears. its not a bad thing to actually run that cool you'll just use more gas.

 

Running too cool can hurt power too - especially on a carbed car. I had a 160 t-stat and electric fans running all the time in my camaro - it actually picked up about 15hp by putting in a 180 t-stat and setting the fans for 200 degrees. TPI cars are the opposite - the cooler, the better (within reason).

 

On a 730 ecm and datalogging, right before the "quarter" mark that you are talking about its about 160-170*. The temp gauges on our cars are an optical illusion. The quater mark to the 220* mark is only about 50* difference. The 100* mark (1st) to the quarter mark is about a 70* difference hence the thought of overcooling. I always thought mine was overcooling until i hooked up my datalogger and found out. Next time if you pay attention it takes alot longer to get from the 100* mark to the quarter mark then it does to get from the quarter mark to the half way mark.

*note* you also have to factor in rising momentum.

Check this post.........Overcooling?