I'm driving and my 86 TA with a TPI 305 was running great- on the highway about 90mph at 2200rpm. All of a sudden I look down and see my temp gauge shoot up to 240* so I pull over quickly. After an hour of waiting the car cools and I manage to get 2 gallons of ice water. The car ran perfectly all the way home, although if my rpms were over 1800 the car would slowly go up to 240*. Any ideas on what it could be, I'm stumped.

My single fan works.
Radiator wasn't excessively low in the first place.
Air dam is in place.

 

Clean your radiator and condenser. Look for obstructions in front of the condenser, and between the radiator and condenser. I once sucked up a plastic sack a ran over in a walmart parking lot. I went from perfectly cool, all the time, to 220-230. I drove it like that for a few days before figuring it out. You would think they would just fall off and down when you stop moving, and the fans go off, but they don't.

If you don't find anything in the process, at least your radiator and condenser are good and clean, and you haven't spent any $$$ on parts yet.

One other thing...don't ever put ice water in an overheated car. You're better off with HOT tap water. Ice cold water can crack an overheated block.

 

Well I put the cold water in after I had the fan running for an hour so the car was a rather cool. And I didn't turn on the car right away so it didn't flow through the engine block.

Anyway, what part is the condensor?

I'm going to replace my hoses and thermostat. I only run my car in late spring-early fall, so would upgrading to a 160* thermostat be a good idea? I'm also thinking about getting a new higher flow water pump like from Flow Kooler or just Summit Brand.

This may sound stupid but isn't the fan supposed to blow towards the radiator? Mine sends air towards the engine block.

 

It's a puller fan, it pulls air through the radiator from the front, and out over the engine.

If you want a lower t-stat, go with a 180*... our cars were designed to run fairl warm, and 160 is a bit of overkill. I imagine you have a circulation problem if it's overheating on the highway and your air dam is in place, but just to be safe, check for any obstructions under the car like mentioned earlier. Replacing the hoses and t-stat is a good place to start. When you finish replacing them, make sure everything is flowing properly as the car heats up. If water doesn't flow after the temp hits 180 (or whatever t-stat you got), it may be the water pump or an obstruction in the lines or radiator.