Mine is doing it with the 85mm, I'm thinking of throwing the 82mm pulley on to see if it corrects it.
My 82mm VMP stage 3 is doing the same thing. Has anyone's tuner identified root cause? I have Justin from VMP doing a remote dyno tune on Wednesday - I will update when finished.
I have the same issue with a VMP stage 2 85mm JLT 123 cai m6 car. When I put it in neutral and coast the car would die Justin said to block the air intake that comes from the grille to the airbox, he said it could be causing to much turbulence, and that has worked so far. I was also having slight surging issues when I would let off the accelerator slightly then the car would surge or feel like a push pull.
My tuner said the same thing (Lund), however when I blocked it off, I don't think it helped that much....nor do I want to block off that cold air inlet permanently...
My car is a 2011 TVS, 85 mm, stock air box, T56 Magnum XL, that also failed to idle from time to time when the motor was cold. This issue began the day the Magnum went in. After a retune, it now fails to idle when it's hot. It will be going back to the shop to fix the stalling as well as this damn clunking noise in the 1-2 shift that's driving me nuts! My RXT is clattering at idle too.
FWIW. I run a JLT and my car has never stalled.
Can any tuners confirm that it's ok to swap from an 85mm to 82mm without a revision?