i think the only differnce is the more amount of pleats in the pure one. bypass should be the same for that it is for the same car. the other differnce is i think the anti drain back valve. the plus has a regular rubber i thinka nd the pure one has a silicone one which is much stronger. we are talking about anti drain back valves in bobs other post in that we think that it is causing more resistance. but thats only speculation.
i just bought a purolator premium plus today just to try and see if i get engine ticking. then ill hit up purolator pure one filter and see if i notice a differnce.
i wish that i had more resources to find out things like we are asking (size, filtration, bypass, media etc.)