My 89 Auto Coupe has 78K. I live in Tampa, FL=traffic and hot weather. I have a 160 thermo, and a new H20 pump. and a adustable fan controller so it's on over 160 and off below it. very basic controller. The car has the original A/C condensor and radiator. Car runs 225F easily in daily driving with the A/C on. 225 w/out sitting hardley at all!!! Just wondering if anyone else's does see 225 on a regular basis. YES i've taken the whole Radiator sysetm out, cleaned it... clean/vacum the junk out every 3k. I think the A/C condensor is beat up from garbage and debre. the radiator doesn't look bad.. .. Let me know what your guys's run in daily traffic.

 

87 L98 195 thermostat, Stewart water pump, manual fan switch. 90 F stoplight, fan on, (a/c not working soon to be fixed), coolant goes to 200 F and back down to 195 when underway. With GM waterpump, coolant would go to 220. Your 160 stat isn't doing squat for your coolant temp because it is wide open all the time. C4's don't have a radiator big enough for you to operate at 160 F except in winter, they were designed to operate at `180 or 195 depending on year.

 

I'm a newbie here so I'm sure there will be some better answers, but my 85 was running 210 ish on our first 90's day here in just a 5 minute stop and go traffic "jam". As mentioned earlier it immediately goes back down below 200 on the highway. In reading various other posts, it doesn't seem like you are out of whack given your climate. I believe if you do some searching you'll find that you need to have the ECM reprogrammed to operate fans at cooler temp if you don't manually override, I also believe the thermostat issue is addressed. As mentioned by the first reply, I don't think the 160 does anything for you.

 

Is your thermostat opening, or opening all the way? Have you burped the system?

I run a 160, with stock WP and a reprogrammed chip to make fans come on at 195 and off at 175. She never sees 215 (oil), even in the worst traffic and the hottest and most humid days in SC. During summer it usually runs right at 200F oil and about 185 coolant.

 

Vader86, you state your coolant temp is 185. At 185, your 160 stat is wide open and you might as well not even have it in the car. It has no effect on your operating temperature. Your operating temp is determined by how fast the radiator can get rid of heat the engine is making and your coolant temp is going to vary all over the place according to ambient temp, vehicle speed, etc. One thing a thermostat does for you is to maintain a constant coolant temperature which promotes engine longevity. Widely varying temperatures is not good. For the life of me I cannot understand why you are a proponent of 160 F thermostats when by your own admission they clearly DO NOT provide a lower coolant temperature.

 

I run around 194F while driving and 210F if I'm setting at a light. IF get caught in heavy traffic I see temps around 227F. Something to keep in mind is what are the fans set to come on at? That is what is going to keep the car cool. My 96 the fan settings are still factory so the fans don't come on until 225F and turn off at 217F. This is one of the main reason I'm fixing to get a programmer for mine. I want to try to keep it around 200F. I would see when your fans are kicking in and go from there.


[Modified by Corvette1996LT1, 11:02 AM 7/2/2003]

 

It runs at 185 Coolant now, in hot weather in thick traffic. She gets up to 195 in the heavy traffic, and comes right back down to 175. (If no real traffic, it never gets to 195) She usually settles somewhere in the 180s. Before the chip reprog, it would run 190-210 in heavy traffic.
On the hwy, it runs in the 170s, and never gets hot enough for the fans to even come on once.

Whereas it ran at 205-225 before, in hot weather with stock fan settings. And ran right at 195-200 on the hwy. (clean radiator front also)

So it did lower my average coolant temps.

Yes, jfb, of course its going to get up to 228 if i stay in town and had no chip reprog. I dont dispute you on that fact, because our radiator is too small for the car IMO. One day when my SR and 383 are in the car, I'll probably put in a BeCool and Stewart pump and reevaluate what i need for stat temp to keep the car in the same approx temperature range.


[Modified by vader86, 12:16 PM 7/2/2003]

 

" At 185, your 160 stat is wide open and you might as well not even have it in the car. It has no effect on your operating temperature. "

Wrong, if you look at a thermostat when it's wide open the opening is a restricted opening that will slow the coolent speed across the radiator!


[Modified by grapeknutz, 6:42 PM 7/2/2003]

 

A thermostat does a few things. 1st it will fully open at the temp desired 160, 180 etc. 2nd job is for it to create a restriction for the water. EVEN AT FULLY OPEN it still creates a restriction. NO thermostat would really F your day up. You would get hot spots, and show cool temps. Not good. Run a freakin thermo. 3rd job is to help stop cavitation in the water pump. a little resistance will help out. REMOVING a thermostat is NOT GOOD!!! I have just been wondering what other corvettes run in daily driving. that's all. MY FAN comes on at 160F, and off at 160F. That's pretty dang simple. so my fan comes on at 160, but the car still gets to 225 and the fan has been running the whole time. I think i'm going to Get a new A/C condensor and Radiator and then go BACK to the Green Antifreeze.

 

On my 85 I'm running 197 on the highway and around 200 in the city w/o the A/C, with the A/C about 203 on 100+ degree days. Up until last week, I've been wrestling with high temps.

With a 195 therm and a chip to kick on the fan at 208, still had problems. I replaced the catalytic converter last week and the temp fell. Coolest it has run since I purchased the car more than a year ago.

Somthing to take a look at.

 

I just runs plain hot!!!! :reddevil

 

I'm going to replace the A/C condensor and Radiator. and put some chicken wire up in front so trash doesn't hit my A/C condensor. B/c I just did some research on our C4 radiators and come to find out, yes they are small, but the technology involved is sweet. It comes from some NASCAR technology, and it's all in the Fin design. all i know, is that our small radiators will work more efficiently than some huge monster redneck radiator, BUT BUT BUT, the minute that fins is looked at funny, your done. OR, dirt, yrs of daily driving... done. ALSO, a not so good or close to 100% perfect A/C condensor. So i guess rule of thumb would be by the 10yr mark all of our Condensors and RAd's should be replaced. I saw a new custom compnay making these fancy grille's for the under part of the C5's so trash doesn't get in. I like that idea alot. but i can make one for a lot less $$. I'm also probly going to put a Pusher fan on the front to help the efficiency rate. b/c above 50MPH my vette runs pretty good temps, but below that, i'm done. so i'm thinking the Ram effect is pushing more air in that the fan can't push idling or going 35mph. I'm pretty sure i'm on target here. Also, i'm going to put a new napa premium Tstat with a small hole drilled in the deck to help stop tstat cyling.

 

Running in South Florida, A/C on, 180 thermo, rad and pump about 4 years old - I get 220 around town.
But, I just had the head gaskets changed because of an overheat problem so I have been monitoring temps very closely the last two months. No overheat problem yet, but the oil looks higher than it used to. It can get up to 260, but the book says not to worry till approaching 300. Hmmm,,,,