SUpposing everything (thermo, fans working, no exuast leaks, fresh tune up, etc...) is in good shape....what improvements can I make to reduce my average temp by about 15-20 degrees? I'm also looking to make it so the car doesn't reach peak (overheating temperature) so easily.

thanks!

 

Heh. My car ran a lot hotter after a complete tune up. :-)
The thing ran so hot (with a coolant flush, new t-stat, and new water pump) that I had to pull it over an let it cool during the summer if I hit traffic.

1) Reprogram/custom chip & low temp t-stat. This cured it for me! I can sit in traffic all day in the middle of summer now.

2) Clean that radiator!!

3) Ram air. I did the Vortex ram air mod that scoops in outside air instead of the hot under the hood air. Runs plenty cooler while driving.

4) Water wetter. Haven't tried it yet, but I hear mixing it with the 50/50 coolant mix could lower you 5-10 degrees.

5) Turn off that AC!

 

have a chip burned to turn your fans on earlier
160 thermo
clean the radiator front
bottle of water wetter

thatll drop them a huge bit

 

Clean the debris out of the front of your radiator (that you can't see and don't know is there). The best way is to remove at least the radiator shroud and better still is to remove the radiator. Also, clean and straighten bent fins on the a/c condenser, both sides. C4's have either a 195 (early) or a 180 (later) thermostat in them. The radiator is sized for these temperatures and to run lower temps requires an aftermarket radiator. Most temp soaring occurs when stopped or below 35 mph when inadequite air is flowing through the radiator. You can install a manual switch to force the fans on, or install a chip programmed to come on at a lower temperature which will help. In hot weather with the a/c on, hot air from the a/c condenser flows through the radiator making its heat ridding capacity less and you will have to expect higher coolant temps. Don't bother with a 160 thermostat because it won't do squat!!! If your engine temp gets well above 180, then your 180 stat is WIDE open and so then will a 160 stat. The temperature of your engine is not solely controlled by the thermostat!!! Excursions to 220-240 at stoplights will not harm your engine and the 15 psi radiator cap will not allow the coolant to boil, so relax , do all you can to maximize air flowing through the radiator. If you can't stand it , buy a 2 row aftermarket radiator and install it.

 

If you don't have a factory oil cooler get one of those. That should do the trick. My 85 runs at 170-175 on a 95 degree day with the ac on. How you ask, well here is my formula.

1. Z-51 car (bigger radiator, factory oil cooler, factory aux fan)
2. 160 thermostat
3. hypertech or ADS chip (depends on my mood) which turns the main fan on at 180 degrees
4. clean the rad. housing out as well as flush the rad. once a year
5. put timing to factory specs (changing your timing can make your car run hotter

 

I dont think the factory oil cooler is any help at all, an aftermarket one could help though.

 

I think mine helps out. My oil and water temps are almost identical. My oil temp is usually 180 while the car is at 175.

 

I've done everything here but the Water Wetter, and I no longer have any cooling problems. I should have done these mods on Day #1.....

 

Water wetter dropped the temp. on my corvette, when I had it, almost 10 degrees. Just like most of the guys said, just clean out your rad. and make sure that your chin spoiler is still attached and upbroken.

 

Yeah, my chin spoiler's a bit broken (only on the black bottom part, a few too many bottoming-outs). It's not bad by any means, but if you looked at it closely you'd see that the center part of the chin spoiler (black bottom part) near the radiator is pushed back a slight bit, but it's not like it's dragging on the ground. I guess I'll stop by a tuner in Santa CLara and have him clean off the radiator, and reprogram/burn the ECM/chip (i have a 94 auto lt1). Maybe I'll try some water wtter too.

 

since you have an 94, you could just buy a Hypertech PP and do it yourself, might save you some money plus you would be able to play with shift points and the rear gears someday

 

Here is what I did with my ’90 L98 automatic. I have historically been having over heating problems. Has never gotten to boiling over but would get dangerously close to the red hazard area in stop and go traffic. The '90 does not give a digital read out of the temp (without going into the computers diagnosis mode) has only an analog gauge that reads from 100 to 260. Looks as if the red hazard area would be about 250-260. I had grounded out the cooling fans so that they ran all the time to try to keep it cool.

Last year I pulled the shroud and shot water through the radiator from the back to clean out the fins. Unreal what came out of the areas right in front of the cooling fans. Looks like it may have been blocked solid in those areas. That would be good preventative maintenance for any C4. But this year I was getting a small water leak. Could not tell where it was coming from but the lower radiator hose was wet on top up by the water pump. So figured the pump may be going.

I pulled the radiator and cleaned out all the cooling fins. Thought about taking it to a radiator shop for cleaning but it did not appear that bad, inside looked good. Then I pulled the stock pump and replaced it with a Stewart Stage I pump. This pump claims to flow about 40% more then stock. Put it all back together, filled it up with tap water (no anti-freeze), added Prestone rust inhibitors and a bottle of Water Wetter, ungrounded the fans, and installed a 180-degree thermostat.

Results: The highest the gauge has gotten is half way up the gauge. That was on 95-degree day in stop and go city traffic. Normally is running between one third to half gauge. I am happy What did it? Don’t know if it was any single item or just a combo of all of the improvements. But if you are running warm and have never had the radiator out, I would recommend pulling and cleaning the radiator. That will probably be a huge step to solving your problems.

tom...

 

Where would you mount an aftermarket oil cooler?

 

I just got done pulling the radiator and cleaning it off and reinstalling it.......

I'm currently going through the fill with tap water, run, drain repeat until water comes out clean......

When I fill the car, I am going to fill with a 50/50 mix of the green Prestone as that was what was in it before.........

Last night when filling the car for the first time, I noticed that the temp did not go above 200 degrees while idling for quite some time......

Have to report back with the final results.......

 

When I put the Stewart pump on mine I asked the Stewart people about what coolent mix to use. They said to use just tap water and add a bottle of Prestone Rust Inhebitor. No antifreeze. That is no antifreeze except for the amount needed to keep car from freezing. So during the summer, just tap water. Here in central Texas, freezing is not a real issue, so will run tap water year around. If further up north, then may want to run tap water in summer and change to an antifreeze mix in winter. The Stewart peoples thinking was that anti freeze did nothing to cool the car, only kept the water from freezing.

tom...

 

Contributors who mentioned that they refilled their systems with
tap water might want to check out some of the recent threads
about overheating, headgasket failure and corroded cylinder heads.

If you are lucky enough to live in a climate where you don't need
freeze protection and you want to ignore Corvette's
recommendation to use a glycol mix, at least spend four bucks
on distilled water to help ensure that the inhibitor you toss in
doesn't immediately have to start work counteracting the nasties
that might be in the tap water.

Just my $.02 worth