The MX-5, from what I remember, takes about 7.9 seconds to hit 100 km/h... I still can't believe C&D's 6.5 second time to 60 mph... atmo corrections or not... the 6.9 other magazines are getting (C&D's SAE corrections are usually about that optimistic) seems better, but I can't help feeling that there's no way you can get an MX-5 that fast except at a drag-strip.
FWD cars will be slower off-the-line... but not necessarily from weight transfer... just due to the inadequacy of suspension geometry to keep the tires on the ground. Front-engined RWD cars also have similar issues, though to a lesser extent... but it's there... in fact, in some RWD cars, they design some softness in the rear to
allow weight transfer, which means bad things for the handling. In FWD cars, you want to prevent weight transfer to the back, which means a stiffer rear... which means
good things for the handling.
Still, a FWD car is handicapped off the line, but once underway, it can hold its own, and thanks to clever traction control, torque-limiting strategies (a la Mazdaspeed3) and, of course, better tires, they can be quick at anything past a standing start.
235 is
not an excessive size for front-tires, for a front-driver. especially a new one... I know some track-junkies running up to 265 in front on older FWDs... which weren't designed to take more than 215... for newer cars, which already have bigger wheel wells and fitments, it's not unknown for tuners to stick 245s on in front. This is what's on the Civic Type R that beat the S2000 at the racetrack... same tire compound, same sizes, same power... the Civic had 245/205 and the S2000 had 205/245... the Integra that lost to both was stuck to 205s since it couldn't take wider tires.
The Golf GTi R that was tested in Sport Compact Car from 0-60 in
well under 5 seconds had 265 tires in front, and that was apparently no handicap on the racetrack. Oh... it did have R-Compoundds... so that may be construed as cheating...
