Suggestions on 455 engine mods

[Stage1muscle]

Hey everyone,

I just joined this forum a couple of days ago, and so far I love what I see . . .from everyone . . . keep up the good work!

As for the subject of this thread:
I own a 1972 Buick GS 455 (Stage 1). I recently had the engine rebuilt after a piston cracked and scratched my cylinder wall all to heck. I chose to use a 1968 buick 430 I had as the replacement based on how well it would accept my Stage 1 parts, and besides it's rated at 360HP stock.

Other than the 430 block and new 10.2:1 compression pistons, the remainder of the parts came from the 455 Stage 1 (or are new Stage 1 spec). Heads, crank, cam, carb, etc.. The only other new addition would be a switch to a hotter Accel coil with new 8mm shielded sparkplug wires. Other than that everything is stock 1972 Stage1 specs.

I was just wondering what everyone's thoughts were on what I should do next to increase my performance. I am certainly getting headers next, since we all know Buicks love to breathe easy. What about switching cams, or getting rid of my "Quadra-junk" carb? Electronic ignition? I have no idea what my HP or torque numbers are at the current moment, but I am always in persuit of better performance.

Any comments would be more than welcome. Thanks!

[curtis73]

Absolutely switch cams. The 30-year-old technology in that bumpstick can be truly trumped by today's cam technology. Don't get rid of the Q-jet. By far the most advanced carb ever to come out of the the US ever. People call them Q-junk because they are nearly impossible to tune unless you're a master. Trust me on one thing. When you have all of your parts ironed out, send the Q-jet to Jet Performance, shell out the cash, and tell them what you have. They will send you the best performing carb you've ever bolted on any engine. I consider myself a good carb tuner, but those folks over at Jet are geniuses. The Q-jet is load-based flow. Properly tuned, no carb will give you more accurate metering or better efficiency than that Qjet. You also have a nice example of a classic and keeping at least an appearance of stock looks might keep its value a little higher.

Having said that, buy a Rochester carb book. That Qjet is not a very common piece if its the original S1 455 carb. Not only is it your wisest choice, its a rarity.

By all means, just a simple HEI swap with a good MSD or Mallory factory replacement distributor is a very wise investment. Since you might rev a little higher with the Buick, go ahead and invest in the MSD electronic module. Much better spark above 5000 rpms, and a $70 investment.

Most importantly, the Buick's weakest link is the oiling. Go to TA performance's website and get their front cover and oil pump. It is a complete fix for the weak stock oiling and will save your butt.

Not sure why the 430 displacement, though??? Why not machine the 455? Really great bore/stroke ratio and more cubes?