By way of interest, I recently measured a stock new transporter van, standard suspension, no load, at 700/700 mm front/ rear. ( bottom of rim to arch)

My transporter campervan when fitted with the RR suspension and trip ready at 2800kg measured 680/650 mm f/r, and now with the Lovell's constant load rear springs, sits at 680/680 f/r. Also measured a new campervan, same conversion, with standard suspension unloaded at 2340 kg at 680/680 mm.
Interesting!