BDR OEM radiator/cap/pressure

[socalliving]

Hello all. Just want to say that this site was a great resource when shopping for my cobra two years ago. Thank you for all who responded.

Background on what I have:

Engine: 408W, OEM rad(BDR), 16" electric fan(BDR), header tank, and 180 stat

Been running great, fan would kick in at appropriate temp, never ran over 195 degrees.

Then: noticed weeping from the cap and found the upper seal had been compromised. No big deal. Old cap had no lbs printed on it. Called engine builder, they use 16 or 18 based on my engine. Replaced it with an 18, went for test drive and came back and it was spitting fluid and from overflow and a little from upper rad hose at the water pump. Placed a 16 on it and did the same but not out the rad hose?

My question is: is the engine builder correct? Do I have other issues? What psi should the cooling system be running at? Also, how good is the OEM rad from BDR and should I upgrade? If so, any recommendations on a better radiator?

Thanks for your help.

Want to get back on the road.