I would assume the difference in whp numbers is going to boil down to what dyno its on. all dynos read differently, mustang dyno's, dynojet dynos and dynodynamic dynos will post similiar but never spot on numbers as ive seen living in my 4 cyclinder world. also, dynos from different states seem to vary alot also, ie: north east dynos to down south florida dynos.
My second guess would be the difference in carburated l's to his fuel injected l. i skimmed the thread but is this car running a stock 280z ecu or a aftermarket standalone. i would wager that being the huge factor in him making more whp then most.
but it boils down mph in the 1320.
beatiful zed by the way !
stratton.