I have about 25k miles on my Southbend Stage 3 Endurance non-silent, and 98% of the miles was at 501WHP, while the remainder was at 440WHP. Made about 10 passes down the drag strip with a couple different drivers (myself included) with no issues.
Not sure if they stock piled the kit or are just the reseller for CM but I will email them to make sure
check it when you get it, and if you get the old version email CM and i'm sure they'll replace it. they're selling fast so hopefully anyone that continued to sell the old version after it was replaced got rid of them by now.
I assume the newer version is the grey steel one? My mechanic bought his CM FX400 right around the same time I bought my FX350. I got the grey steel TOB/slave cylinder and he got the black plastic version.
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