I think that I talked about how much overvoltage the 7135 chips can take, it was not about leds. Or is ghe quote from another of my posts?
Anyway, none of the red XP-E2’s can handle 3A. Apart from that they max out at just above 2A, the red led types are much more sensitive to warming up than blue leds, so even at 2A you can see the output lowering after a while.
But there are 660nm leds that can handle 3A, i.e. the 660nm XP-G3, a pretty cool led with a bit larger die than XP-E2. I bought it from Mouser and tested it 2 years ago but never made a proper thread about it. I did post some test results on BLF buried in another thread, and it can be found via via signature link. But here it is: [Postponed] Sofirn SP10R - deep red AA/14500 EDC - #55 by djozz
And then there is the Luminus SST-20-DR 660nm, I don’t think anyone has bought or tested one but it also has a larger die than XP-E2 so should handle 3A.