i am going to eventually have a beefy 350 in my truck capable of over 400 horsepower and i am deliberating what type of secondaries to go with... since its heavy and relatively geared for low-rpms, should i get vacuum secondaries? it will have a comp cams 262 hydraulic flat tappet cam, so it will have decent but not excellent vacuum, somewhere better than 10-12 at idle. would i just have to swap out the power valve to one that opens at less vacuum since the carb is prolly configured for stock vacuum levels?
any ideas and suggestions muchly appreciated, thanks