I need to give some background on the situation.

I wanted to clean up my engine setup so I went ahead and started pulling what I had thought were unnecessary items out from under the hood. All the extra emissions crap like the Air Pump, A/C, vacuum lines, etc. I also had replaced the radiator at the same time because I had broke a piece off my stock radiator. Car seemed to run fine after that. A little over a week later I noticed that my temp was getting high....like 215*~220*. My fan is electric and it is wired to a switch that I control from inside the car. Whether I was doing 25 MPH or 50 MPH the car would reach 220* fairly quick. If I went over 50 MPH the temp would continue to climb until I slowed down. I swapped thermostats the other day with a Stant stock 195* one and the car was at 260* before I shut it off. I assumed the thermostat was bad. I then bought a Duralast 180* thermostat and a new Duralast water pump. Changed all that stuff two days ago and I am getting mixed results. The car will always climb to 220 in about 5~7 minutes but sometimes I can watch the gauge sit at 220* or it will drop to 180* within 30 seconds of reaching 220*. But then it climbs right back up to 220* w/o missing a beat. I can drive over 50 MPH it seems now but I'm at a solid 220* most of the time. I say 'most' of the time because sometimes it will stay solid at 180*. The last few days have all been the same weather here....mid 70's.

Now from what I've been told....the passenger side exhaust manifold has a 'heat riser' that redirects hot exhaust back thru the engine to help heat it up quicker in the winter time. I removed the vacuum line that was attached to that and was told that maybe the 'heat riser' is sticking and forcing the hot exhaust back thru the motor all the time now.

8 out of 10 times my temp gauge is reading 220* and I really don't like that. I usually turn my fan on manually at around 160* but even when I turn my fan on right when I start the car it seems to make no difference at all. Idle or driving the car will hit 220* and stay there but never go over 220* unless I'm racing around like a madman.

I've owned this car for 4 years now and have never had any trouble like this before until just a few weeks ago when I got brave and pulled all that stuff from under the hood. I can't put it back to test it since I broke some things getting them out. The 'Heat Riser is sticking' explanation seems viable since the engine temp climbs pretty quick and other times my gauge never reaches 220* and stays at 180*.

Any assistance is appreciated in this matter.
Thanks

 

Sound like your cooling system is working fine, except that it has this switch hacked into it (and all the rest of that hacking-up you mention).

Put the missing front air dam back on. That'll take care of it heating up at speed. It should stay within 5° or so of thermostat temp, even without a fan and even in 110° ambient, at any speed above about 30 mph, by way of the air flow directed to the rad by the air dam.

 

I'm not really sure how to fix your problem, but on my 84 L69 my normal temp is 220. If the engine gets hotter than that the fan turns on and it will drop a little bit below 220 then the fans shuts off and the engine will get back to 220. Sometimes on a cool night if im driving around and not getting a lot of lights or am on the highway the engine will stay below 220 and my fan won't turn on. But for city kinds of driving on a warm day 220 is about what mine sits at.

 

The air dam has been in place since I've owned the car and is still in good shape.

The manual fan switch has always been wired like that since I've been in California with the car and I've been able to do 65 MPH on Cali highways without any sign of 220*. Now on Illinois highways at 55 MPH my car sits at a nice solid 220* [with a 180* thermostat] and it's not even a hot day. Something has totally changed since I pulled out those items from under the hood. And I did happen to test this new thermostat before it went in and it does open up at 180*.