What do you think - would a bypass on the spring under the brass cap help much? I'm think'n it might on these modded setups. It looks like a high quality, (beryllium?) spring but it's carrying a ton of amps through it. We are probably over 25 amps and thinking the output curve on the SBT90.2 is probably flattened out anyways (djozz LED test), so probably not much of a factor.
Hhmmm... Maybe it would help to hold higher amps for longer