Well I have a 89 formula 5.0 TPI and it gets a little too warm, it will creep up to almost 3/4 and then drops back down to half but it only does it at idle and it also surges and runs lean. I've replaced the thermostat, and did a coolant flush anything else I should do? I'm thinking that maybe my fans are coming on a little too late any ideas? I was thinking about adding a oil cooler but I dont really wanna dump anymore money into this set up.

 

first you need to figure out why your car is running lean because if your car is running lean not only will you have surging but also running lean causese your engine to run a little bit warmer i would check sensors and all that jaz if all that checks out you might look into getting some new cooling fans from your local auto parts stor the electric ones are pretty cheep and very reliable just some ideas

 

The fans don't come on until the car gets pretty hot in the first place. Also,