Cool on a hot day

Jim Craik

Lifetime Supporter
This may have been covered before,

Today was very hot, while driving my spf 40, I found that if I closed the side window vents the inside pressure from the ac fan was enough to keep the heat from the front of the tub from leaking through.

Much cooler!
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I'll have to try that Jim. I've been considering an insulator since, even with the a/c, the heat is pretty bad. I have also removed most of the padding from behind the seat...which might also be a contributor.
 

Jim Craik

Lifetime Supporter
Litumup

I have also done some sound proofing and insulation to the firewall, it makes a great differance!

I removed the carpet and first put down some Dyna-mat for noise and then some insulation that look like small bubble-wrap with aluminum backing and re-installed the carpet.

One other thing I did that helped alot, I got one of the thick Lexan firewall window replacements from Oltoff in Florida, a very nice peice of kit.

As of yet I have not done any work to insulate the front of the tub, but in the meantime keeping the window vents closed seems to help alot!
 
I am curious, are some superformance gt40 louder than others ? The reason I ask, is that the one I drove with a small block 427 was just plain unbearable. Are all these Superformance gt40 like this or do they very? I have a Pantera can they be quited down or is this as good as it gets?
 

Jack Houpe

GT40s Supporter
Jim, the biggest help will fix the front nostrils so the radiator heat doesn't heat soak the foot well. I did temp readings before and after and the foot-well area of your car is about 105 degrees if you haven't changed the nostrils. After the fix, it dropped down to low 80s. The change over isn't easy but I have pictures if you need them. The heat here in Arkansas with humidity is well in excess of 100 everyday now and my car keeps up. I did find that in the winter I didn't need the heater before the change over, all the heat from the radiator heated the foot-well and the engine heated my back. Glad your on the road!
 
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Jack Houpe

GT40s Supporter
I am curious, are some superformance gt40 louder than others ? The reason I ask, is that the one I drove with a small block 427 was just plain unbearable. Are all these Superformance gt40 like this or do they very? I have a Pantera can they be quited down or is this as good as it gets?

Yes, they are loud, no room for mufflers. Ear plugs or bose's headsets on long trips. All my friends who own Pantera's and GT40s know that the difference in cars is like day and night. I once owned the oldest know Pantera to exist, it was nothing like the GT40.
 

Rick Muck- Mark IV

GT40s Sponsor
Supporter
While prepping a couple of SPF chassis today it struck me that the brake cooling intakes on either side of the radiator intake are blanked off, that is the tube that would feed the brake cooling hose is there as is the intake on the nose but the tube is blanked off by the inner fiberglass structure. All one needs to do is trace the tube opening onto the inner glass panel and cut away. You will get all the air from the left and right nostrils into dumped into the front behind the nostril panel. Of course, it will be ambient air, but that will always be cooler than what is coming out of the radiator! This could provide a good flow of air to wash away the excess radiator flow. It will also dump water in front tray when it rains, but overall I think it will reduce footwell temperatures.
 
Jack,

Can you please elaborate on the front nostril mod? Although I have a MKII, I'm hoping what you've come up with might work for me.

Rich.
 

Jack Houpe

GT40s Supporter
Jack,

Can you please elaborate on the front nostril mod? Although I have a MKII, I'm hoping what you've come up with might work for me.

Rich.
You have the best air outlet of the SPF GT40s, the Mark II has the single outlet which directs all the air outside, or lets say much better than the MK I. The MK I has about 33% of the air from the radiator heat soaking the front of the tub and creates pressure coming out of the wheel well area with the duel nostril outlets. I took a IR gun and took readings of every part of the inside of the cab looking for heat, the foot well area and the rear bulkhead was the hottest part of the car, both heat soaked from either radiator or engine, 105 F on the front of the tub and 117 F on the access cover of the front of the engine. As you all know an AC unit can only do so much but by reducing all the heat soak I have made it much better than when first purchase. Adding insulation and sound deadening all helps but redirecting the air from the radiator really did the trick. The MK II outlet is great, if you seal up the area where the single nostril exits around the radiator I think this would be all you can do beside insulate the foot well area. I know these are race cars but I am in my mid 50s and need as much comfort as I can get while I can still get around. :) The first of these pictures are from my templeting the area where I wanted the air to exit, notice the foam around the fans that seal against the new outlets I fabbed. I used poster board to form the pattern then fiberglass mesh and fiberglassed everything. I am not a body man so anyone know better way please chime in.
 

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Steve C

Steve
GT40s Supporter
Jim,

Good call on the "closing toll windows with A/C on"; it does improve A/C performance.

I have done what Rick suggests above (cutting out the brake tube openings) and have no noticable heat soak in the footwell.

Also have upolstered removable closed cell foam bolsters behind each seat that prop the back forward 2" and act as thermal insulation (see pic in SPF forum under 2125 upgrades). With individual bolsters if a tall passenger rides the passenger bolster can be removed for seating comfort.

Steve P2125 (MKII)
 

Jack Houpe

GT40s Supporter
Jim,

Good call on the "closing toll windows with A/C on"; it does improve A/C performance.

I have done what Rick suggests above (cutting out the brake tube openings) and have no noticable heat soak in the footwell.

Also have upolstered removable closed cell foam bolsters behind each seat that prop the back forward 2" and act as thermal insulation (see pic in SPF forum under 2125 upgrades). With individual bolsters if a tall passenger rides the passenger bolster can be removed for seating comfort.

Steve P2125 (MKII)

The MK IIs really have a much better design on the radiator air outlet. The SPF version of the early MK I is not like the original cars at all other than the looks from the top.
 
You have the best air outlet of the SPF GT40s, the Mark II has the single outlet which directs all the air outside, or lets say much better than the MK I. The MK I has about 33% of the air from the radiator heat soaking the front of the tub and creates pressure coming out of the wheel well area with the duel nostril outlets. I took a IR gun and took readings of every part of the inside of the cab looking for heat, the foot well area and the rear bulkhead was the hottest part of the car, both heat soaked from either radiator or engine, 105 F on the front of the tub and 117 F on the access cover of the front of the engine. As you all know an AC unit can only do so much but by reducing all the heat soak I have made it much better than when first purchase. Adding insulation and sound deadening all helps but redirecting the air from the radiator really did the trick. The MK II outlet is great, if you seal up the area where the single nostril exits around the radiator I think this would be all you can do beside insulate the foot well area. I know these are race cars but I am in my mid 50s and need as much comfort as I can get while I can still get around. :) The first of these pictures are from my templeting the area where I wanted the air to exit, notice the foam around the fans that seal against the new outlets I fabbed. I used poster board to form the pattern then fiberglass mesh and fiberglassed everything. I am not a body man so anyone know better way please chime in.

Jack,

Thank you Sir. I'm probably going to extend the ducting or build some side and lower ducting out of aluminun to help seal but I think my biggest problem is the rear bulkhead and tunnel. Maybe some expandable foam might help these areas.

Rich.
 
An additional problem on some cars is the AC ducting going to the dash vents is crushed (during assembly) and does not give you full low from the blower.
I am going to pull the dash out and change them as mine are flattened.
Dave
 

Jim Craik

Lifetime Supporter
My car may run cooler and quieter as I have a 302 based engine after puting in the Dynamat and such the noise level is much lower.

I always though that the main differance between the GT40 and the Pantara is that I never pretend I'm driving a Pantara. (sorry, I could not help myself).
 
I am curious, are some superformance gt40 louder than others ? The reason I ask, is that the one I drove with a small block 427 was just plain unbearable. Are all these Superformance gt40 like this or do they very? I have a Pantera can they be quited down or is this as good as it gets?

If it was a SB427 with FI and the eight stack inlets, it is louder than say my 427FE with a single carb....increase the airspeed into a smaller intake (or 8 of them) and it will be louder. I can carry on a normal conversation at cruise with the thicker rear window and firewall upgrades.
 
On tthe topic of A/C, I was talking to Debra S. of Superformance and she mentioned that their GT40 had A/C lines pinched during construction and the A/C was marginal. They replaced the pinched pipes and the A/C blows much colder. She made it sound like other cars could be afflicted with the same issue. I don't have specifics, but she should (or she should be able to get them).

Mike
 

Jim Craik

Lifetime Supporter
Spydermike,

You may be on to something, my right side dash vent blows much stronger than the left, any thoughts on how much work to replace the crushed hoses and are they standard type or do I need a special SPF one.
 
I haven't any idea what they look like. I imagine they are some kind of SCAT type convoluted tubig, but I haven't looked into it and I am not near my car.

Mike
 
My dash is currently, should I say floating. All the screws are out but it’s still tethered with wires and such. I did notice that one of the lines to the demister is crushed and unless I move the outlet to another spot under the demister grill it will never work at all. If you sitting in the car it’s the one on the right. I’m going to take a peak tonight before I bolt it all back together to see if there are more issues.

Can anyone tell me does the A/C compressor come with oil already in it?
 
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