i'm thinking you are thinking right. The E & F pumps (I run an F in my Taylor) have a shorter and steeper suction housing and the pressure difference from impeller top to bottom rears it's head sooner than the longer pumps. If the perssure to the top of the impeller drops low enough, cavitation happens.
Dad ran my Taylor back when new to 72 on Nitrous back in '79 after DuaneHTP put the nitrous on, tuned the pump, and modified the rock grate to a sorta-loader. We had no hi-sped cavitation problems.
I'm now running a pro-loader I bought from him last spring. Due to the scarred up hull, I was only running 64 or so this past fall, w/o the fun-gas and still breaking in the rebuilt engine so I can't say much about it otherwise. $180 or so, new, larger bolts/screws included, I'd buy one.
http://hi-techperformance.com/