maybe a thicker top would help.

 

My NB has struggled keeping me cool. I also have a small leak in the AC that I cannot find, so even when I hit that sweet spot of refrigerant- it only lasts for ~2 months. I have insulated the floor and trans tunnel very well using a layer of foil backed tar paper stuff for sound deadening, then a layer of foil backed insulation, and in some places I used jute felt over that. I must say the insulation addition was noticeable to me.

I prefer my system slightly overcharged. I usually end up just over 30psi on the low side, with a high idle speed, probably around 2k rpm. I have used Enviro-safe 134a replacement "Freon" and I think it works great, somewhat noticeably better that 134a, but I find myself picking up a can of regular 134a at Walmart to top off when it gets low. I pay $5 for a can at Walmart, the Enviro-safe is not much more money but it takes pre-planning, which I am not so good at. What bothers me about my system is that at full cool settings, with a "hot" cabin" my unit still cycles.... I have not yet diagnosed what is telling the compressor to stop and take a break....

On a hot Florida summer day, my AC is plenty cold if I take a drive at 3pm in the afternoon, when the car was just in the garage or shade. Starting the car when its been in the sun is another story as it takes quite a while to cool down. The vent temps are cold- as low as 36-37 degrees, but it still struggles to cool down a hot car. This leads me to believe its either an air volume thing, or an insulation thing.

My windows are tinted, but with cheap tint. I can actually feel the difference in coolness when I'm in the shade of a cloud, even if its just briefly. My next step is better tint!

 

Joe, this might help you with the cable adjustment.
https://www.miata.net/garage/heater_cable.html

 

Damn rabbit holes!

http://www.possumliving.com/2012/08/...e-air.html?m=1

 

Same story here in extremely hot days. I believe it is some sort of pressure switch on the high pressure side, but have not searched into it yet.

 

if the pressure switch didn't kick it off, it would blow the valve and splooge a bunch of the refrigerant. cycling is normal. most/all cars do it

 

I thought I saw you dicking around in the same rabbit hole.

 

Thank you! That helped a lot. Mine seemed pretty good, but I tightened it up a little more to make sure no heat is sneaking by.

 

You can adjust the heater cable and still get heat in there since the foam gaskets could easily be dust by now. I've had mine blow in my face every time I move the damn temp lever.

 

Mine worked pretty well in both the dry central California heat (105F+) and the South Carolina swamp heat (95 degrees, 72 degree dew point). Then I listened to a friend and removed it because racecar, and now I can't drive the car when it's summer anymore :(

 

My experience thus far with my Honda Fit and NB1 (with a slightly low charge) has been that they're **** in traffic (when you need it). Once you get rolling, the compressor really starts to work for me. My NB1 before I took out A/C was comfortably cold if I was revving it out a bit.

 

For about 10 minutes on Monday, my A/C improved immensely. Happened about 2:30 in the afternoon. Right here in upstate SC.

 

Yeah I've had plenty of people try and tell me how my car would be fractionally faster and easier to keep cool on the track if I would just ditch that darn air conditioning. If the car didn't have air conditioning I could set it on fire and use it more often. It's absolutely essential for dehumidifying the air in the cabin and making the car even drivable 6 months out of the year. Unless I'm on the track I don't want to show up anywhere with clothes soggy from sweat. And you can actually die of heat exhaustion sitting in traffic in the car without air conditioning here. It's considered a life support system for 4 months in the summer if you've got a hard top on it.