What is the top speed of a Grumman LLV?

Interestingly, in the 70s, the USPS had AM General make a handful of electric-powered DJs. They could travel at 33 mph. If you were a mail carrier driving one of those, I imagine transitioning to a LLV would seem like stepping up to a racecar, pokey pushrod 4-cylinder engine, 3-speed slushbox and all.