1970 Pontiac GTO - Humbler to Rumbler

Sure, we'd all like to say that our GTOs are as fast, can handle as well, and stop as well as modern performance machinery, but the truth is that they can't excel in all of these comparisons in stock form. However, vintage GTOs can be built to compete with late-model performers with the aid of a solid plan of attack, mechanical aptitude, and an armful of aftermarket catalogs.

Enter Craig Pachar, whom with his dad Brinson, purchased this '70 GTO 6 years ago at the age of 14. The plan was to clean the Pontiac up to make it a driver and be a father-and-son project that resulted in a high school graduation present. What you don't know is that Craig's dad had owned, restored, and raced GTOs for years and is the proprietor of Triangle Speed Shop in the family's hometown of Orange, Texas.

Needless to say, the plan to build an easy streeter soon developed into a frame-off buildup with much more than stock replacement parts. "I wanted a GTO but wanted it to be modernized with the best parts and technology available," Craig said. With a family-owned speed shop and a desire to be an automotive engineer, you can see why this now-20-year-old auto technician and Lamar University student would covet such aspirations. The results of dad's and his own vision is this '70 GTO.

Except for the obvious 17-inch Boyd's Smoothie 2 wheels with wide Cooper rubber and its lower-than-stock stance, this Goat appears factory fresh on the outside. There is a reason for this. Craig explains, "While I knew that I wanted a GTO, I just needed to decide which year. Finally, I found the one that I was looking for--a '70 model with a 455. I like the '70 because of the sharp lines of the fenders and its other subtle changes from the previous years." With timeless styling, there was no need for drastic body mods.

Engine And Drivetrain
Beneath the hood was a different story, however. The 455 cubes has given way to 467 thanks to an overbore of the 455 block to 4.180 and the installation of an Eagle crank with 4.25 stroke (stock is 4.210). A set of 6.800-inch Eagle H-beam forged-steel rods were employed to connect the Ross forged pistons--wrapped in chrome moly rings--to the crank via Clevite bearings at the big end and full floating pins at the small end. Melling's high-volume pump sips from a stock oil pan and delivers crude where needed.

A custom Comp Cams solid roller lifts the valves from their seats via Crower lifters, Trick Flow pushrods, and Crane Gold 1.65:1 roller rockers to the tune of 262/272-degrees duration at .050 with .646/.652 lift and has a 108-degree lobe separation angle.

Edelbrock heads were ported, resulting in 296 cfm on the intake side at .600 lift. Ferrea 2.11 intake valves were installed, but on the exhaust, the seats were machined to accept larger 1.77 valves. A three-angle valve job was performed, and the valve springs, retainers, and keepers are from Comp Cams.

Compression checks in at a usually-too-high-for-pump-gas 11:1, but Craig claims that he can run 93-octane on the street without detonation. At the track, he runs 110-octane race fuel and bumps the timing to 40 degrees.

BIGS Performance (Altoona, WI) supplied a 950 Stage 5 carburetor, which is bolted to the Performer RPM intake through a 1-inch HVH Super Sucker Spacer. Jet sizes are #78/#83, and fuel delivery is provided by a Holley Blue pump and regulator. Ignition is capably handled by an MSD Billet distributor running 38-degrees total timing at 3,000 rpm. The coil and wires are also from MSD, and the plugs are NGK FR4.

The task of ushering combustion remains to the atmosphere falls to the Indian Adventures headers featuring 1 7/8-inch primaries and 3 1/2-inch collectors. A Dr. Gas X-pipe with 3-inch inlets and 2 1/2-inch outlets joins the flow and delivers it to Walker Ultra-Flo mufflers and Torque Tech 2 1/2-inch tailpipes.

Channeling all of this power to the rear via the driveshaft and HD U-joints is a '70 Turbo 400 trans with a reverse manual valvebody. It was built by Bakers Transmission in Orange, Texas, and connects to the crank via a TCI flexplate and a serious 4,500 stall Hughes converter. Out back is a '70 12-bolt Posi with Moser axles and 3.55 gears installed.

Suspension And Brakes
Lest you think that this GTO is simply a racecar with very nice paint, I think it's time we discussed the suspension and brakes. Though the '70 GTO was one of the best handlers of the bunch by Nixon-era standards, it can be improved upon today. To that end, Craig installed Eibach Pro-Kit springs front and rear to lower the GTO's stance and increase the rates. Up front, the factory 1 1/8-inch stabilizer bar remains, but in the rear, a Hellwig 1.00-inch Antisway bar was installed to further thwart lean in the corners. KYB gas shocks were chosen to better control jounce and rebound, and urethane bushings can be found reducing deflection throughout the suspension system. Boyd's 17x8.5 and 17x10-inch wheels with 245/45ZR17 front and 275/40ZR17 Cooper Cobra rubber in the rear keep the GTO stuck to the street.

What good is mountain-moving power and great cornering if you can't stop? Realizing the performance potential that the GTO now had in other areas, Craig smartly decided to upgrade the braking system with a set of big 12-inch Aerospace Components disc brakes featuring four-piston billet aluminum calipers for the front and the rear. Not only will they loosen your dentures on deceleration, but they also look great between the spokes of Boyd's wheels.

Conclusion
This father/son project took four years, and its initial investment of $3,200 to purchase the Pontiac swelled to $30,000 to build it. So far, it has won Best of Show in four local events and a Best Interior award. The Golden Goat also captured a First place in the Altered class at the Southern Nats in 2002 and won awards at the 2004 Southern Nats. What does Craig like best about his Goat now? "I am happy with all of the mods that I have done to bring this classic GTO up to date, and I like having all that power at the touch of the throttle. I drive the GTO on weekends and to shows. It's totally street legal fast and beautiful." Future plans include further upgrades, more detailing, and possibly an overdrive trans. Given the execution of the mods seen here, it would seem that this Humbler has certainly graduated into a Rumbler.