Anybody knows why Mazda whent from 1.1 to 0.9 radiator caps?
 

I searched allready and didnt find an answer. A .9 bar cap will open the system sooner than a 1.1 cap causing the water to boil earlier. I just installed a 1.1 cap and a AST and most people dont recomend that because of Mazdas recalls; but nobody has a explanation about it.

The laws of physics says that water boils at a higher temp when is at higher pressures. All of us FD owners would like to buy as much insurance to prevent the failure of a O-ring(rotor housings) , therefore delaying the water from boiling by raising the pressure should do the trick(about 10-20 degrees). Some say the extra pressure is not good for the hoses but its only 3 more pounds those hoses will easily hold 10 more pounds.

Raising the overheating temperature 10-20 degrees higher seems to keep us from engine rebuilts and the only drawback would be putting 3 more pounds of stress on some hoses that will probably would not even feel it.

What do you guys think? Im I missing something?

fisrt of all the fd's had 1.3bar caps on them. the recall changed the caps to .9, and all of the throttle body hoses, plus if nessesary the water pump, upper radiator hose, water level sensor (they came in a kit). this is also when they put in the fan control kit
the stated purpose of the recall was to keep coolant fron leaking on to the top of the engine and having the car burn down.

mike

They must of have put hoses that cant hold 1.3 bar so thats why they when down to 0.9 bar caps. wouldnt you agree that a 1.1bar caps would be extra insuranse if the hoses were upgraded?

They must of have put hoses that cant hold 1.3 bar so thats why they when down to 0.9 bar caps.
wouldnt you agree that a 1.1bar caps would be extra insuranse if the hoses were upgraded?

we have been putting the 1.1 caps on for years, they seem to be the perfect compromise, .9 is too low unless you drive like an old man

mike