My '87 auto n/a seems to hate thermostats - seems there's not enough coolant flow through the engine but it seems to be running a lot warmer than normal (not quite overheating) with a thermostat in. Is it reccommended to keep the thermostat in the car? If so, what's a good brand / temp. opening for it?

yes thermostat needed

and i think temps are 180deg

When I got mine at Advance they offered a 160, 180 and 190. I think then you might want to get the one that suits your climate, but like she said, you do need one or it will overheat. Check out your fan clutch too, it should be kind of slow to turn when cold, not free wheeling and the fans when the A/C is on.

Russ

Yep, replaced the fan clutch and water pump a few months ago; swapped out the thermostat at that same time but I think I got a faulty one. I decided to go with a Failsafe at 180. I live in Dallas, TX, so heat is definitely an issue.

Strange, though... w/o a thermostat in my car (I'd been running it that way for about a month) it never came even close to overheating except one time when I forgot to refill my coolant back to normal spec.

sounds very familiar to me

yes dd it is de ja vu,isn't it?.

Okay, added the thermo, overheated, shut down before it redlined.

Took thermo out, ran it, overheated, shut down before redlined.

No white smoke... no coolant in oil... no oil in coolant... no gurgling noises behind dash... though I'd been experiencing some coolant loss in the months past. I know my radiator drain plug gasket is shot, I'm leaking slowly via the heater hose on the back of the engine between the valve covers, leaking very slowly from two hoses off of the block itself. Day before last I'd run some block sealer / head gasket repair through the cooling system to seal it off... bad move. I think it may have clogged the cooling system. Problem is, it's my day-to-day driving car and I'm short on funds financially. Suggestions?

replace the head gasket

Take out the radiator and get it cleaned out. Before you put it back in, blow out the lines with clean water, open drain on side of engine. Pull the hose ends off the heater and flush that out too. There is a radiator flush you can try from the local part stores. Then fill it up with plain old water and try to find the tester for head gasket leak I have heard others talk about on this forum. That at least should let you know if the gasket is leaking.

It is amazing just how fragile the head gasket seems to be on these cars. The last quite a while stock but eventually they do start leaking, like all cars do. It is not always a blown head gasket when the engine starts to overheat. Water leaks, fans not working, fan clutch not working, etc. I still think the car needs a bigger radiator. I put one in mine and it works great and it has been over 100 each day for quite a while. I put an electric fan on it and I love it!

I have gutted the thermostats in a lot of my cars and they all ran too cool. It doesn't always work that way, but I thought the Supra would react the same way. You just can't have any air in the system with these cars either. Make sure your radiator cap is working right and allowing water from the purge tank to be sucked back in the system as it cools down.

Let us know how it works out. Driving in this heat is a pain in the ass with an overheating car. Too hot to run the heater...lol.

Russ

go to autozone and get the flush kit. it connects to your heater hose. you put in line of the heater hose and turn on your garden hose. it will flush whatever crap is clogging your system.
drive it.
if it keeps getting hot, check the summitracing.com for a radiator. call them if you like, just measure your radiator beforehand. keep in mind where the hoses go. they can sell you a universal aluminum radiator cheap, that you can install.
it will keep it way cooler.