AH1951 wrote:As Joe lives in a tropical climate, it might be wise to blank off the heater inlet and outlet connections at the engine, throw away the Rancid Valve, discard the two miles of heater hose, block off the water connections to the heater box, and get the air conditioning working.
Oh, and ditch those clips that hold the bonnet ajar.
It completely ruins the beautiful lines of the car.
Rancid Valve I went in the chip shop late after the pub yesterday, "Got any chips left" I said, "yes" said Georgio .. "well you shouldn't cook so many then"!!
Grant. You win. The hood risers are going this weekend. I just used them when the heat was 95 and above for two months we are now in the 70's and low 80's. The blower system works and I have no heat buildup in the car. I did note some heat coming out of the far right AC vent but just closed the vent. The big test was the wife. No complaints. She actually enjoyed the ride. The new Jaguar XJS 4 Pod Calipers with the same pads (RedStuff). Really do the Job along with a 94 F150 master brake cylinder. RacerJoe
Grant. You win. The hood risers are going this weekend. I just used them when the heat was 95 and above for two months we are now in the 70's and low 80's. The blower system works and I have no heat buildup in the car. I did note some heat coming out of the far right AC vent but just closed the vent. The big test was the wife. No complaints. She actually enjoyed the ride. The new Jaguar XJS 4 Pod Calipers with the same pads (RedStuff). Really do the Job along with a 94 F150 master brake cylinder. RacerJoe
Hi Joe, did you need to make mounting brackets to fit the XJS Calipers?
Also the master cylinder, I presume you mean 1995 F150 Ford Truck do you Joe?.. did that fit the original Jensen Servo/booster then?
With kind regards
Grant
The fibreglass drain tray/air duct has to be a consideration of how heat can be drawn into the cabin.
Placed out of the way in an area where little or no heat evacuation happens there is no insulation and a big cut out at the rear corner I presume for wiper mechanism maintenance.
When it gets a little too hot switching on the cabin ventilation fan draws air via the tray/air duct so I have taken the step of insulating and when re-fitting will fully seal it up.
From an earlier post have made sure foilcloth is covering the gap between firewall and wing tops.
Water tray. Do you not have a metal deflector insulated with heat reflectant to keep engine heat from not getting past the tray area. There was a factory effort to keep engine heat from getting past the tray. RacerJoe
Aslef. If you peel back the silver foil from the front of the water tray and you see three holes where screws may have been removed. The factory made an air deflector to keep engine heat from bei gang pushed against the firewall and past the water tray through to the cock pit. The reason for my hood risers was to release the heat and back pressure forcing engine heat to enter the car. The heat evacuation system really has made a big difference. Outside the car you can really feel the hot engine heat. It is all cumulative in causing heat sink. RacerJoe
Thanks for the info Joe,when it's all reassembled I will be paying particular attention to sealing up all around the area.
As you mention cumulative effect plays a big part of the problem.
As an aid to getting as much cool/fresh air into the cabin I have inserted heat resistant tubing to the air ducts that carry air from the front of the car to the footwell air boxes.
Rap72. The diagram indicates that the heat buildup at the rear firewall which I was trying to evacuate with my two marine fans was in theroy correct. I have never seen that drawing. Yes the hood risers let heat out and some could be drawn into the vent. I do not have all the answers but as far as my efforts so far I have not experienced the heat buildup I remember. So far so good. RacerJoe
That drawing was from the workshop manual I bought through regalia. I know Ross Hockley in Australia had plans to move the battery to the boot ( trunk ) and then use a fan to the vent to extract the Hot air that way. I don't know if he did it though. Keep at it.
I applaud any effort t correct short Cummings of the Interceptor I can tell you that the heat generated by the block and the exhaust manifolds is excessive for the Interceptor without some help. My next move would be to install two more marine in line fans toward the rear of the tranny tunnel trying to evenly pull the firewall heat away from rising toward the air vent. I feel the pressure from the two big radiator fans just puts too much back pressure of heat to the firewall. RacerJoe
Tim. I do not have all the answers but you have to keep the engine running at the correct temperature first so with that said then do what you think will help solve the heat buildup at the firewall. Your car your option. A lot of what determines what is the discomfort you have to deal with. My objective is total comfort at a relative easy effort. RacerJoe
I went in the chip shop late after the pub yesterday, "Got any chips left" I said, "yes" said Georgio .. "well you shouldn't cook so many then"!! 
) and then use a fan to the vent to extract the Hot air that way. I don't know if he did it though. Keep at it.