I'm trying to choose a lightwt flywheel. Jun has a steel one weighing 14 lb(?).
One of their marketing claims is that their product won't "warp or distort like aluminum". Jwt, unorthodox, rps and stillen are aluminum. Nismo and jun are steel. So my question is has your aluminum fw warped? If so, can you give details? If not, can you post how long and under what conditions you have been running your aluminum fw? thanx guys.

 

The JWT for approx 7k mi with no prob..

 

Aluminum has a low melting temperature... it definitely could warp under heat load (lots of clutch burning). Steel is MUCH denser though, but certain steels i.e. inconel are extremely heat resistant. There is a tradeoff between the weight of the flywheel and the durability over long term. Of course, nismo and Jun may have optimized the weight/durability ratio which would be in your best interests. You don't want to go too light with Aluminum and have to replace the flywheel too often, right?