I bought Ron's old machined 225mm flywheel. I think he had it down to around 14lbs or so. Ron am I right? Anyway, I run it on my 240Z with the L28 bonestock, with triples, and headers. It will never see anything past 6000 in this config, so it should be OK. I run the Fidanza on the turbo car. I love the effect of the light flywheels, it really fits my style of driving.