Yes, it will work, but it will drive your WP and alternator slower than the 280Z unit. I have run this crank pulley with the outer pulley milled off for weight savings, for 3 years now with no ill effects.
FYI, It's actually called a Harmonic Balancer, or crank pulley. Both belt grooves are smaller diameter, and also smaller width by quite a bit on the 240 crank pulley. If you have AC, then you'll run into a problem. The smaller belt won't hold up to the pressure of driving an AC compressor, nor will it withstand the tighter tension needed on an idler pulley type belt. I'd suggest sticking with a 280 crank pulley. Do it right, or don't do it at all.
Z man of Washington
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