Q: My 1967 GTO has a 455 Pontiac powerplant with Edelbrock 87cc heads, .030 over Ross pistons, Total Seal rings, Eagle rods, a Crower cam (int./exh. duration 248°/252° @ .050″, lift .512″/.524″, lobe separation 112°), 1.5 ratio rocker arms, and Clevite bearings.

The engine was shop built and balanced, and is also equipped with an Edelbrock 850 cfm carburetor, Torker II intake manifold, MSD 6AL-2 ignition, and a Mallory Unilite distributor. My drivetrain includes a Centerforce clutch, Richmond Gear 5-speed (3.25:1 first gear), and a Moser 9″ Ford rear end with a 3.25 ring-and-pinion. I’m also running Hoosier 26″ x 9″ x 15″ slicks.

My car weighs about 3,650 lbs. (with me and a half tank of gas) and launches at around 3,600 rpm. My 60-foot times are from 2.0 to 2.2 seconds, and my ¼-mile time is in the 12.70s. I’ve seen GTOs in magazines running in the 11-second range (with less cam and inferior heads).

What’s wrong with my setup? I need some help!

a dark blue 1967 pontiac gto with a 455 pontiac v8 under the hood
(Image/OnAllCylinders)

A: It sounds like you’ve built an awesome hot rod, so let’s see what we can do to lower those ETs!

Your 60-ft. times should be closer to 1.5 or 1.6 seconds to get the results you’re looking for. If you’re using traction bars, tuning them might help you get off the line quicker, plus your 3.25 ring-and-pinion is not the best choice for drag racing.

We suggest that you move up to at least a 3.70 rear gear—Richmond Gear’s 3.70 set is a great choice for high performance street and strip duty. With the proper ring-and-pinion ratio, your Goat should be turning between 5,600 and 6,000 rpm when you cross the line.

Finally, you should check your fuel pressure at full speed and in high gear to make sure your engine is being fed properly!

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