Actually, they are both 901 threads, period... so that shouldn't/couldn't be different. I checked both the LR and HV and the wick over the bridge inside are the same size, even.
I must have picked the right one to use at 6V, as I haven't popped it in the last few days. THough I only get about 4-5 hits off it before my 2 drops evaporate completely.