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Making Great Cars Better typography

BY Ron Ceridono Photography by Rob Fortier

1. Performance Online supplied all the parts and pieces to update our ’65 Chevelle. Virtually everything that was done to it is applicable to ’64-72 GM A-bodies.

BY Ron Ceridono Photography by Rob Fortier

Making Great Cars Better typography

Brake and Suspension Upgrade for GM A-Bodies

T

he ’60s were interesting times. The average new house was around $20,000, gas was roughly 30¢ per gallon, miniskirts were popular, and the Rolling Stones were touring the U.S. Of course, for many gearheads, the high point of the decade was the introduction of General Motors’ A-body lineup in 1964. It included the new Chevelle Malibu (and El Camino) as well as the Oldsmobile 4-4-2, Pontiac GTO, and Buick Skylark. A V-8 Malibu carried a window sticker of around $2,600, and the others were similarly priced.

Although GM’s A-bodies were great cars and well received in their day, by today’s standards they have some shortcomings when it comes to stopping power and handling. GM began installing disc brakes on ’65 Corvettes, but the rest of GM’s offerings had to wait until 1967 for a disc brake option. There were some notable A-bodies with lots of go and very little whoa. And while the performance versions of these cars had impressive straight-line performance, thanks to their spongy suspension, bending them around corners at speed often resulted in white-knuckled drivers, while the tires squealed loudly in protest.

Recently, we had the opportunity to follow along as a number of brake and suspension improvements were made to a typical A-body by the team at Performance Online (POL). POL has been in business building and restoring custom and classic cars as well as selling performance products for over 30 years.

Disc Brake Conversion

One of the biggest improvements that can be made to any drum brake–equipped A-body is the installation of a POL disc brake kit, as stopping power is dramatically increased. While the example shown here is a ’65 Chevelle, the parts and procedures for this brake conversion (and all the other updates shown) are similar for all ’64-72 GM A-bodies (check with POL for specific applications).
For ’64-72 Chevelles, POL offers complete kits to convert from drum to disc brakes that include:

OEM forged spindles for disc brakes
OEM caliper brackets
OEM dust shields
POL’s forged disc brake steering arms

These kits use single-piston OEM or Wilwood dual-piston calipers—they will not work with OEM four-piston calipers.

Master Cylinder and Booster
When updating to disc brakes, a power brake conversion should be part of the package. The brake system’s hydraulic pressure is increased for more stopping power, while the driver’s effort to stop the car, even in a panic situation, is reduced.

POL’s master cylinder and booster kit includes:
9-inch-diameter power booster (8-inch, dual diaphragm is optional)
1-inch bore master cylinder
Proportioning valve with bracket and lines

It should be noted that when installing a vacuum booster the angled mounting bracket will result in the integral pushrod connecting to the brake pedal at a lower point than the manual master cylinder push rod did (see photo 17). If the lower hole isn’t there, one will have to be drilled.

Steering
Unfortunately, no matter how cool the car was, time and mileage will make mechanical parts deteriorate—and our Chevelle was no exception. To cure the ravages from years of regular use the critical front suspension components of our 57-year-old car were replaced with a performance tie rod end and idler arm kit that included:

Inner and outer tie-rod ends
High-performance tie-rod adjusting sleeves
Idler arm (GM used 13/16– and 7/8-inch-diameter idler arms on A-bodies—check with POL for your application)
To completely rejuvenate the steering system we also installed a new centerlink.

Springs
To replace sagging original springs, POL offers a wide variety of replacement A-body front coils that maintain the factory spring rate. They are available in stock height or 1½-inch drop.

Rear springs are available in stock, 2- or 3-inch drop. Stock height spring rate is 138 lb/in, lowered have a slightly stiffer 152 lb/in spring rate.

Shocks
The POL team advises that shock absorbers are among the most overlooked items when upgrading or rebuilding the suspension. POL’s shock absorbers offer the advantage of dialing in damping ratios with three-way adjustments.

To adjust the shocks, they are fully collapsed, then the shafts are rotated to the desired setting:

Valving ratios are:
Front: 90/10, 80/20, and 60/40
Rear: 70/30, 50/50, and 40/60

Sway Bars
POL’s sway bar kits are designed to minimize body roll, understeer, and oversteer when cornering, resulting in improved vehicle handling and control.

Kit includes:
11/8-inch-diameter front antisway bar
1-inch-diameter rear antisway bar
Polyurethane bushings

Making Great Cars Better

GM’s ’64-72 A-body cars, like our Chevelle, were truly great cars. And with suspension and brake upgrades, they can be made better than new. Now if gas would go back to 30¢ per gallon …
the parts provided in the POL kit are laid on a work table
2. Everything needed to convert from drum to power disc brakes is available in one coordinated package from POL. Note the vacuum booster bracket is at an angle and the pushrod is attached.
two brakes from POL’s disc brake upgrade kit for GM A-body lineup, one on its back and the other on its face, sit on a table top
3. A substantial increase in stopping power can be had with POL’s disc brake upgrade kit for GM A-body lineup. This is the best way to make the whoa match the go.
view of the current and worn stock springs
4. With the drum brake and spindle assemblies removed, the stock springs were given the heave-ho and joined the rest of the antiquated parts in the scrap metal bin.
the new 5160 alloy steel spring from POL, installed
5. POL’s replacement front springs are made from 5160 alloy steel and are powdercoated black.
mechanic greases and assembles the disc brake kit provided parts
6. Our POL disc brake kit came with new bearings, seals, and retaining hardware. All you must do is grease the bearings and put everything together.
close up of on of the Chevelle's period-perfect Cragar S/S wheels still attached to the car
7. Our Chevelle was equipped with period-perfect Cragar S/S wheels and they had to stay, which isn’t always possible with aftermarket disc brake swaps.
a mechanic works on a removed Chevelle wheel on a work table top
8. POL offers several disc brake upgrade kits. The OEM-style kit will work with 15-inch aftermarket and even 14-inch Rallye sport wheels.
two steering arms resting on a table top
9. Steering arms are different for drum and disc brake applications, compare the stock drum brake version on the left to POL’s forged disc brake replacement on the right.
mechanic drills a larger mounting hole on the steering arm
10. POL’s A-body forged steel steering arms are designed to fit most ’64-72 models with 7/16-inch mounting holes. Some spindles use ½-inch bolts, so the holes in the arms must be drilled larger.
a steering arm in place, attached with Grade 8 bolts and lock nuts
11. Our new POL dropped spindles used the larger ½-inch bolts. After drilling the steering arms, they were attached with Grade 8 bolts and lock nuts.
mechanic holds shock absorber during installation
12. We opted to install POL’s adjustable shock absorbers that offer three extension-to-damping ratios.
a new POL drum with GM single-piston calipers and new vented rotors installed on an axle
13. The POL disc brake kit we used to replace the original drums came with GM single-piston calipers and new vented rotors.
view of the exposed push rod from the brake pedal
14. With the original drum brake master cylinder removed, the push rod from the brake pedal can be seen. It must be removed to install the power brake assembly.
mechanic holds the old single-reservoir style master cylinder in hand with the new updated one installed in the background
15. Not only does the new brake system include a vacuum booster, but the car is now updated with a much safer dual master cylinder to replace the original single-reservoir style.
close up of POL's new disc brake master cylinder featuring an AC Delco-type proportioning valve that includes low-pressure warning light wire and plug
16. POL’s new disc brake master cylinder comes with an AC Delco-type proportioning valve that includes low-pressure warning light wire and plug.
arrows point to the two pushrod holes present on the current brake pedal
17. Most brake pedals have two 3/8-inch pushrod holes 1 inch apart. The upper is for manual brakes (arrow 1) the lower for power brakes (arrow 2).
view of the newly installed rubber brake hose
18. Included in the POL brake kit are new rubber brake hoses. Also available is a hardline kit for converting a single-reservoir master cylinder to a dual.
the new and original tie-rod ends sit side by side on a table top
19. To replace the worn original tie-rod ends we installed replacements from POL along with solid adjusters rather than using the stock split sleeves and clamps.
underside view of the lifted car, showing the new sway bar in place
20. POL’s 11/8-inch front sway bar will improve cornering dramatically without compromising ride quality (we did not add a rear sway bar).
the old and new sway bars sit side by side on a table top
21. The new sway bar comes with replacement endlinks equipped with polyurethane bushings.
close up of the polyurethane bushing installed with the new sway bar
22. Also included with the sway bar were polyurethane bushings. Note the flats for a wrench and the lock nuts on the tie-rod connectors that make alignment easier and more secure.
inner underside view of the POL disc brake system
23. POL’s disc brake spindles are available in stock ride height, or with a 2-inch drop. The new rotor splash shield is also part of the brake kit.
new shocks and springs sit on a table top awaiting installation
24. With the front suspension updated, we turned our attention to the rear and added new shocks and springs.
a POL rear spring in place
25. POL’s rear springs are powdercoated black and come in stock and lowered heights. At the bottom of the coils are small loops, or “pigtails,” for attaching the springs to the axle housing.
a POL rear shock in place
26. Like the front shocks, the rears are three-way adjustable to alter compression and damping performance.
mechanic fills the master cylinder
27. The last step in the update process was to fill the master cylinder and bleed the brakes.
Performance Online
(888) 216-7478
performanceonline.com
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