Sorry op not trying to hijack thread. Reason I asked about vacuum is I am building 470ci 400 block stealth heads 440 source .035 stroker kit. hoping vacuum will be enough hearing your combo is encouraging. Also you said it was a four speed what rpm did you leave the line at?

I will also be at close to 4000lbs with driver using 3.23 gears and a 4 speed. using Comp Cams Xtreme Energy High Lift XE285HL hydraulic flat tappet camAdvertised Duration .285 int .297 ex/Dur @.050; .241 in .247 ex/ Lift .545 in. 545 ex with 1.5 rockers. Lobe Separation Angle 110.