Curious why people are concerned as to the weight of an alternator, does 1 kilo really matter in the scale of how much a zed weighs, also why the need for high amperage alternators if the 240z was built with a 50 amp and that ran every thing i cannot see the sense of upgrading past say 60-70 amp taking into account modern items you may fit in the car, i weighed my 240z yesterday it came in at 1160kg that includes chevy engine, R200 dif, twin 3" exhaust,cast iron exhaust manifolds, half a tank of gas and spare wheel, (but not a 40 + something driver trying to regain his youth in a fast lookin sports car) seriously though i could reduce the weight by dropping the spare tyre changing to exhaust headers( in progress) changing to single 3" exhaust pipe apparently very minor loss in power but lot of gain in less weight, remove the rear anti roll bar apparently not needed on a v8z change the rear drums to discs ( in progress) doing the above would save around 40 kilos+ oh and empty the washer bottle another kilo, doing the maths as now 1160kg/300bhp = 3.86kg per bhp, compared to new 1100kg/150bhp= 7.3kg per bhp obviously these are just numbers and not sure of the exact bhp of engine either but close enough, but to compare reduce it by 40kg is the same as gaining another genuine 10 bhp from the engine, but look at the list to do all the above would cost several hundred £££ for little gain in performance, so overall reducing the weight of the car as a means of more power is not a cost effective solution, with regards to alternators the one on my car is off a linde 6 ton fork lift truck 70 amp alloy body, built in voltage regulator made by bosch and best of all was free.