Just bought a Petit AST. The person that sold it to me is sending me a 13 & 16 psi cap, which got me wondering, which is better and why?

Higher pressure will raise the boiling temperature, right (which would be benefitial for keeping out air pockets)? But will the added pressure increase the risk of popping hoses?

I would imagine that if you run 16lbs on the AST, you have to run 16 for the radiator cap as well, correct?

 

I eliminated my AST and I am now using a 16 psi cap. I don't miss my AST . .. but who knows maybe you don't miss it till its gone! You are correct about needing both caps to hold the same pressure ...... I can't speak for secondary effects of having too much pressure in the system other than to say others people have had success with it.