The enjoyment of owning any custom classic truck intensifies greatly with the addition of each new improvement. There is almost nothing more fun than outperforming some poor unsuspecting soul in his brand-new high-performance whatever-he's-driving with an old pickup. By outperform we mean not only straight-line acceleration, but outhandling and outbraking as well.

Even if you're not inclined to blow the doors off of something, these characteristics are essential to helping your irreplaceable old truck survive on today's idiot-packed mean streets. When the subject is narrowed down to Tri-Five GMC and Chevrolet trucks (which actually could be called Five-Five trucks, since '58 and '59s are virtually mechanically and cosmetically identical to the Tri-Fives), there is an infinite number of high-performance and safety options available.

Almost without exception, the first major change any custom Tri-Five owner goes for is to plug in more horsepower. It's only a matter of time before the trusty ol' stovebolt six-banger is tossed in favor of a small-block V-8. It's really hard to imagine anyone who wouldn't get an ear-to-ear smile the first time they hit the loud pedal-so why stop when you're having fun? Well, if you don't want to end up with your truck appearing as a hood ornament on a Buick, you're going to have to be able to swerve around or stop in time before you plow into the beast.

To be able to handle both skills means faster steering with better brakes. The best solution entails swapping out the Tri-Five's drum brake recirculating ball steering and straight-axle frontend with an IFS featuring disc brakes and rack-and-pinion steering. For the majority of Tri-Fives on the road today, a V-8 conversion with an IFS frontend swap is as far as most guys go. The truth of the matter is they are only two-thirds of the way home.

Even with a stock Chevy 6, the Tri-Five's half-elliptical rear leaf-spring suspension is pretty much maxed out, optioned with a 265 or 283-inch motor, and one is guaranteed wheel hop or axle tramp.

"Axle tramp is a common attribute in powerful, rear-drive vehicles with leaf springs. The unpleasant sensation-also known as wheel hop-causes a loss of traction and an alarmingly bumpy ride under hard acceleration." This definition of wheel hop is from the Ford Motor Company of Australia's website, and it applies to cars. In the case of Tri-Five pickups, where there is much less weight on the rear wheels, all it takes is a six-banger to break 'em loose.

What this translates to for the most commonly utilized powerplant in today's Tri-Fives, the powerful 350-inch small-block Chevy, is a truck that can't leave the line without spinning in its tracks in a fog of burning rubber.

Straight-line acceleration is just the start of things (no pun intended). Now let's talk about the Tri-Five's stock leaf-spring suspension when it comes to brisk highway driving characteristics. The leaf springs' unpredictable behavior while cornering near its limit is caused by the rear of the truck steering itself without any input from the driver. Rear-end or rear bumpsteer, as it is known, is caused by the sideways movement of the differential.

Boy, it's almost enough bad news to make one afraid to drive their stock rear-suspended Tri-Five anywhere, but have no fear, because we have the cure. And not only do we have a solution to this pesky problem, but it's one you guys can handle at home just by following these photos and text.

SOURCE
Total Cost Involved Engineering
1416 W. Brooks St.
Ontario
CA  91762
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