Well I looked at them, they seem to get a decent amount of power and I dont have to put alot on the top end to get the power i want out of it. I found a kit from RPM Machine (someone mentioned them to me) but for about 1700 bucks i get a 3.580 crank, a set of 6.123 I beam rods, forged dome top piston (yea like a hemi :snakeman:). So I thought it a good choice but if you think going to a 390 would be better then just give me some info about them. But I just figured it keeps me closer to a 340 haha