Yep the ole Vmax6 syndrome. I hate that when that happens. The Vmax6 does like the higher nitro. I cured my Vmax6 blues by upgrading to the vmax7. I can run it on 15%nitro and about 3-4 washers. It runs rich like this but with plenty of power. So, If i remove washers and lean it out some, Watchout!!! My plan is that as the engine wears, reduce washers and bump up the nitro
. I dont know if thats a good plan but when I had my vmax6 installed, thats what I did, and the engine lasted a while until It wore out. I still can run my vmax6 but it needs a new piston and cylinder to get the power I would need. Hey, just my 2 pennies.