SPF GT 40 Air Conditioning

I have an SPF GT 40 that is about 6 years old #2178 and the air conditioning has always been marginal on hot days. Does anyone know of improvements to make the system colder ?
 

Rick Muck- Mark IV

GT40s Sponsor
Supporter
I have an SPF GT 40 that is about 6 years old #2178 and the air conditioning has always been marginal on hot days. Does anyone know of improvements to make the system colder ?

First you must have the relay kit to improve the blower fan operation and prevent blowing fuses. Second check to insure you ducts under the dash are not crushed, many earlier cars have them crushed/restricted to the point of 70 percent blockage.

Also keeping ambient air OUT is key, easier to cool if it doesn't have hot air pumping in: http://www.gt40s.com/forum/superformance-gt40s/29631-spf-gt-water-air-sealing-diy-thread.html

As Walt suggested a proper charge is key and make sure the compressor drive belt is properly adjusted and not slipping.

And some dufuss here sells this thing: http://www.gt40s.com/forum/superformance-gt40s/30007-spf-gt40-ac-box-seal-kit.html
 

Dave Hood

Lifetime Supporter
Larry:

I live in Charlotte where our summers can be brutal. All of Rick's ideas are good ones. I've also installed 3M Crystalline Film on the inside of my windshield. It cost about $300, but it dramatically reduces the heat and UV penetration. If that fits your budget, I highly recommend it. There is virtually no tint to the product, so it won't impact your vision in any way.
 

Tim Kay

Lifetime Supporter
^ what Dave suggest ^

I've done the windshield on a couple of my cars and love the results. I went with a light tint on the 40 and was truly amazed at the noticeable difference. For example, the black leather dash in direct So Cal sun is, without exaggeration, at least 50% less heat with the 3M than it was without. Placing my hand flat on the dash without the 3M, the black leather was almost too hot to keep my hand on it.
 

Rick Muck- Mark IV

GT40s Sponsor
Supporter
It is amazing the amount of solar loading that happens in a GT40. Considering the glass/plex ratio to the volume of the interior, it becomes obvious that you will get a LOT of heat via the transparent portion of the car.

Again whatever you can do to reduce the intrusion of heat/ambient air/engine heat will improve the A/C performance.
 
I don't know if your GT40 were built like mine (P2193) but after disassembled mine totally (I had to replace the tub) I've discovered the following about A/C / heat:

- Between the seats and the engine there was only carpet !!! Absolutly no heat insulator.

- Ducts under the dash and especialy the ones to defrost the windshield were crushed/restricted and just a very little amount of air was exiting the windshield grill.

The reassembly is 95% done so I've installed 5 mm heat insulator between seats and engine compartment + new capet and I've bought new ducts and installed/improved their passages under the dash. After testing I get now a big amount of air to my winshield.

Of course I've done many others improvments (control arms / wheel bearings / uprights / etc...).

ROBY427
 
Ummm, I put a cup holder in mine... Coffee and AC... Very nice. Finally got the car titled and promptly have been putting hundreds of miles on it! AC is nice and cool when it's 85-90 out there.. I read in another thread someone lamenting how the GT40 was so uncomfortable... That person clearly never drove a Cobra for 8 hours straight in summer heat. I have a few nice classics... The GT is by far the most comfy... My wife and I are looking froward to the annual Trek to Road America come July!
 

Mike

Lifetime Supporter
Is there a GT40 reunion going on at Road America? Maybe Watkins Glen? VIR? So glad I was able to attend Goodwood for the 74MM since we in the US are so lame and cannot muster an event of our own. How about Colorado on Labor Day weekend for a national GT40 get together? I'll set it up...
 

Mike

Lifetime Supporter
All I can do is show up. The Vail event looks like a lot of fun but just lacks the track day activities. It would be great if we could round up several GT40s to attend. I was really excited for the event at Watkins Glen but apparently it has all lost steam and is lost for good. Regardless, if you are planning on being in Colorado, let me know. We can at least meet for an impromptu get together.
 
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