Has anyone run a tricked out, streetable dual-quad 425 in a Special/Skylark onthe track? I'm trying to decide if I want to run a 425 or 455 in the future. I fell in love with the low end torque of the 401 in my old 'Cat, and have seen where the nailheads make more HP at 2500 rpm than the 400/430/455's do, just curious if it would be possible to get a streetbuilt 425 2X4bbl in a small buick to run in the 11's or 12's.
I have a 66 GS 4 speed with the nailhead and researched this myself a while back. with the limited flow from the heads and the lack of performance parts available it is very difficult to get a nailhead streetable and in the 11's. Mike T is currently working on a kit for the 65-66 GS nailhead cars so that a Belt driven blower can be bolted on. i believe i will be the first buyer of his kit and will be having Jim B build the engine that it goes on. i expect to have 500-550 hp with close to 700 ft lbs of torque and an almost stock smooth idle. cant wait to see the look on peoples faces when my stock looking and sounding GS blows their Bowtie butts away. Bob :3gears:
Just look around . Lots of 455s on the street that can run 12s some perhaps 11s. There are almost no nailheads that can do that.
I kinda figured the heads would be the limiting factor on high end... Guess I"ll have to decide between low end grunt for playing with people off the line or alll out racing.... If someone made some aluminum high flow heads for the nailhead that would make a big difference, but would ruin the benefit the nailhead does have, the low end. I really did fall in love with the nailhead in my Wildcat, except for the fact that it went through rockers hand over fist.
