Hi All, ADDED PIC'S
Been a lot of talk about air conditioner shut down during this hot weather due to high freon pressure.
Thought I would pass along some things I have been doing to my A&A supercharged C6 with heads/cam/headers etc-----, to keep the air conditioner cooling during this hot summer at idle, stoplights and after heat soak during shut down.
I have a Dewitts rad, (great product) keeps car cool even at idle/slow speed. The fan however was the stock unit and did not seal very well around the rad face. Got the Dewitts dual fan set up, (very nice). fits very well closed up all the gaps on the engine side of rad and has more clearance to engine than the stock fan. Stock fan pulled 30 amps according to my clamp on amp meter at full load Dewitts shows about 29 amps and flows more air. Go figure. I can actually place my hand in front of the air cond. condenser and feel the pull of air through it, I could not with the stock fan. Engine water temps with 160 deg thermostat run about 175 to 185 during driving above 30 mph, will get to about 210 at idle. This is lower than it ran stock in summer at idle. When stock in summer at idle the air would sometimes cut out on high freon head pressure. The next thing was, The A&A shroud ducting does not close up the sides or top of the rad, There is about 1/2 in along the top of the rad under the cover and down the sides have a good amount of opening. Put some foam under the top shield and around the piping (air inlet and air to maf). Fitted some foam between the condenser and the rad at top. This is to try and get the pull of air to come from the front of the car instead of short circuit from under hood where air is hot. I havent figured out how to close the openings along the side of rad yet. Next I noticed the headers on the pass side, the front tube runs about 1/2 inch from the a/c compressor rear and all the air conditioner lines run along the fender well on the pass side. Only one of which is insulated from the factory, its the return to the comperssor. My handy laser temp gun says the headers are between 450 and 550 degres, they are coated but thats a lot of radiant heat. I got some radiant heat blocker mat from Thermo-tec. The stuff is made to wrap around (but not tight and not completly around) has air gap and opening on side away from a/c compressor. This shields radiant heat from compressor, then hung a flat piece (about 15 by 12 in) in front of remaining 3 pipes, attach with screw clamps. This shields rediant heat from a/c plumping. The high pressure a/c switch is located just in front of the fuse box. The last thing I did was to mount a Spall 8 inch fan to the bottom of the rad between the rad and front cross member, using wire ties. It will pull air from under the car and push it up front of engine over and down where the headers exit engine compartment, you can place your hand next to the header exit (with hood closed) and feel movement of air. It is controlled with a Haden adjustable thermostat with remote temp bulb and relay, also has manual on/off switch you can hook up. Mounted the temp bulb next to the fuse box hanging out over the space between the box and engine. Played with the adjustable thermostat to get the turn on temp I wanted, about 160 on and it turns off (non adjustable) about 135. Used a heat gun to test and set temp. After shutting off engine on 90 deg day after idling in drive for 15 minutes the fan will cycle something like this, 10-14 minutes on, 2-off, 3-on, 4-off, 2-on, 7-off, 2-on, 10-off, 2-on, 15-off, 2-on then stays off. Total run after shut down over 40-60 minutes has not been over 30 minutes. At a max 6 amp draw this has not been a problem and should not be with a healthy battey. Fan will cycle during idle and after shut down to cool underhood temps. I know this is a lot of stuff and may be overkill but no more air conditioner shut downs and air works after heat soak at start up.
Thanks all for your time, hope this is good info.
Haden controll switch for fan, adjustable on temp

Spall fan mount location, 8 inch


foam to seal open areas

radiant shield for front header to a/c compressor

radiant shield for other three header tubes to a/c lines, thermocouple for Haden fan controll

 

good stuff.

 

I'm so sick of my a/c I may just follow everything you did at once! Can you post pics??! Or send them to me?! Nivardomeraz@yahoo.com

Thanks for the great info!!

 

Running less freon in the system is one of the best changes you can make and coated or wrapped headers. Been find C6's with overcharged a/c from the factory for years now.

 

Post of some pictures of your cooling mods

 

^^^^ what he said

 

Will get some pic's and post to night, if's its not too crazy at work.

 

Sweeeeeeet

 

 

Grand Junction, CO. nice
My sister lives in Montrose, I hope to be there in a couple of more years.
You and others are correct about the freon charge being too much. I did take a little out of mine a couple of years ago. Seems I was at about 95psi at 90 degrees when engine cold and pressure equalized, now am at about 86psi, and it did help. I think my manual showed a typical pressure at different given temps for equalized system and I am in the range now.

Left camera at home, will try pics again tomorrow.

 

add pics

Donald Hall

 

Although I don't have/noticed an AC issues but I do have an engine overheating issues which is not been solved yet in stop and go traffic!

I have the same setup as you, A&A supercharger + Dewitts radiator with factory fans then upgraded to Dewitts spal dual fan! still reaching over 242F!
outside temp is 104-110F

Right now, I'm removing the big z06 oil cooler and putting back the small z51 cooler.
Also I'm spacing out the radiator and AC Condenser,,

Using a foam to seal the gaps every where to help the fans to pull air only from front is good idea I would try
Also I will try then adding the fan underneath!! it seems also a good one!

I hope I can drive safely without being afraid to be trapped in traffic then overheating happens!

 

242?!! must have air in the system..

 

Any pictures yet

 

Pic's are up.

 

Try removing your hood blanket. I've seen my temps drop almost 15 degrees all around, city and highway since I did it. Same set up as u

 

Believe me, I'm fighting the overheating issues since day one when I have installed the A&A kit. Then i just got busy with other overheating issues with aeromotive fuel pump as it was heating and leave me stranded on road before the coolant ...right now with RSI fuel system no issue with the pump and can drive long period but again comming back to engine overheating! so i'm working on this now.

No air bobbles in radiator + changed thermostat three times (one of them was factory and working fine on other vette) + installed Dewitts radiator + dewitts dual fan + Don't have hood blanket + I changed my hood to a vented exractors hood.. still overheating in stop and go traffic.


Right now three ideas to try and I hope it will help/solve the issue:
1- removing z06 cooler and buying an oil cooler that can be mounted behind of the fog light as my z51 found it broken!
(Any brand name that will work behind the fog light? not twin cooler or big like the breathless performance!)

2- trying to mount a reverse fan infront of the AC condenser! (what do you think guys?)

3- Sealing the upper gaps between the A&A shroud and radiator.pip/air filter. (done using a wide double tape,,, just to try)

4- Adding a bottle of 40 additive to pure distilled water. (Done)

btw, spacing the AC condenser will nto work as there is no space,, it will interfer with the supercharger inlet filter ot the pip going to the throttle!

and yes I'm getting 242F and more when driving more than 20-30min in stop and go traffic! and this is acheivable with as low as 1400-2000 RPMs only!

Whenever the road opens,,, and increasing my speed with keeping the RPM fixed and low as possible ,,, You can see the coolant temp dropping slowley till 210F

If above things doesn't work in our extreemly hot enviroment,,, then :
1-Remove the supercharger kit! or
2- Park the car and wait for the winter

 

White shark... I don't understand how you are having so many heat issues. My car is worse as far as generating heat, and we are seeing the same temps here right now yet mine is rock solid. I just have a Dewitts with factory fan.

 

5. fire mechanic

 

Are your fans programed to come on earlier?