Q: I bought a 1969 Pontiac Firebird a few weeks ago. I has a factory 400 V8, which I’m told makes 345 horsepower. I’d like to get 600 horses out of this car, but I’m not sure where to begin. Any advice would be greatly appreciated!
A: We better to get to work, then!
Let’s start by getting more displacement. A 455 crank with the main journals ground down .25 inches to 400 main size, boring the block .030″ over, and some 455 pistons will get you up to 455 cubic inches.
A rebuildable 455 would also work and save you some cash. At this level, connecting rods like Eagle Specialties H-Beam rods would be useful.
To complement the greater displacement, you can install an Edelbrock Victor Intake and an 850 cfm double pumper carb, and Edelbrock cam and lifter kit, 1.61:1 roller rockers, 1 7/8-inch Hedman headers, and an NOS Cheater nitrous system.
Use the 150 hp jets, and you’ll have your 600 horses.
Use a 2,500 rpm stall torque converter and a 3.55 gear to put that power to good use. You’ll also want some subframe connectors and a roll cage to keep your Firebird in one piece.