Re: Pick my cam for my blown sbc 350....shooting for 700ish horse
with E85, if I wanted to go for 700hp and the basic build your suggesting, I would like to see at least 210 heads and a bigger solid flat tappet that will make power winding to 6500+ and around 15 or 16 pounds of boost. at 700 hp, you want to see some good parts for relability and I hope it is not a Weiand 6-71 that you are trying to make more than 15 pounds of boost with.
I know some guys that push just over 12 pounds of roots boost with hydraulic FT lifters and some decent RPM with no problems, but I dont see much higher than that. I think for your average hot rod blower motor that comes with a hydraulic roller, they are fine with 7 or 8 pounds of boost, maybe even up to 10 pounds as long as you dont try to push it over 6k rpm. Anymore requires careful planning with your valve springs and dancing on the edge of valve float. Trying to handle the boost levels you mentioned, I wouldn`t attempt. I am running 15 pounds of boost and a HR cam and keep it to 6k rpm, but I would not recommend it to anyone as I had lots of issues and painful learnings along the way and I do it with 175 pounds of set pressure and Morel lifters. My next motor will have a solid cam if I try to run this boost level again, so I dont have to worry again about an intake valve hanging open and a kaboom in my intake, which is not such a nice thing to happen to your blower motor.
1973 RS Z28: 401ci Dart Little M, Littlefield 8-71 supercharger @14lbs boost, Callies Magnum crankshaft, Lunati Pro-Mod rods, JE pistons, 7.8:1 compression, AFR 227 Comp heads, T&D 1.6 shaft rockers. Reed solid FT cam (240/250@.050, .523/.542 lift, 112 LSA), QFT 750 carbs, Tremec TKO-500, Lemons headers, Moser 12 bolt, 33 spline axles & 3.42 gears