I'm going to replace my large ugly plastic header tank with an alloy one from Optimum Balance Products but need to buy a pressure rated cap as well. The ones they sell are rated between 10psi to 20psi (approx) is there a set pressure for the expansion tank cap on a 2.0litre Pinto engine or is it not too important which one i fit

think the standard pinto one is 8psi will have a look when i go out to the workshop later. i do know that a 14psi corsa one is bad as you end up like this when a hose blows off.