Rebuilding a ZZ3 to Make 485 HP
From the February, 2009 issue of Chevy High Performance
By Sky Wallace
Photography by Sky Wallace
A broken ZZ3 crate motor has...
A broken ZZ3 crate motor has been resurrected with new valvetrain components to power Larry Richards' '87 Monte Carlo in the Pony Express 100.
Reggie Jackson's high-performance...
Reggie Jackson's high-performance engine builder John Gianoli checked each main bearing for the proper clearance after torquing the caps to spec.
Crane supplied the steel-billet...
Crane supplied the steel-billet roller camshaft and the other components seen here.
Gianoli always uses a captive...
Gianoli always uses a captive roller bearing behind the cam gear to keep the gear from eating up the block.
After torquing down the rear...
After torquing down the rear main and attaching a dial indicator, the desired 0.006-inch crank endplay was verified.
The SCAT 6-inch connecting...
The SCAT 6-inch connecting rods were mated to Sportsman Racing Products pistons and rings.
The end gap was set, with...
The end gap was set, with the top ring at 0.018 inch and 0.014 on the second.
Before shoving each piston...
Before shoving each piston and rod into the block, Gianoli rotated the crank so the rod journal was at the bottom of its travel. He then carefully guided the rod into place, using his fingers to keep it from hitting the crank.
After torquing all the rod...
After torquing all the rod bolts and checking for smooth rotation, Gianoli applied silicone sealer at the ends and then bolted on the Aviaid oil pan. Aviaid also provided the oil-pump pickup.
With the motor right-side...
With the motor right-side up, the dial indicator was again called into action, this time to firmly establish TDC on No. 1.
After dealing with the valve...
After dealing with the valve seats, Mike Slover, RJHP's in-house porter, gave the heads the customary street/strip porting job.
The heads also had to be machined...
The heads also had to be machined to accept the Crane H11 tool-steel endurance valvesprings and cups.
Manley provided the severe-duty...
Manley provided the severe-duty valves for this motor with 2.02-/1.60-inch intake and exhaust.
Along with the cam, lifters,...
Along with the cam, lifters, and timing-chain set, the other Crane stuff used here included the pushrods and endurance valvesprings (230 pounds on the seat and 610 pounds open).
By removing the spring around...
By removing the spring around the top of the PC seals, a bit more oil is allowed to run down the exhaust valve stem. According to Gianoli, this results in extra cooling for the exhaust valves while still providing proper oil control for street use.
With the rocker arms in place,...
With the rocker arms in place, lash was set at 0.020 inch on the intake and 0.022 on the exhaust.
After being installed on the...
After being installed on the motor, the ported iron Bow Tie heads were fitted with Manley guideplates.
The folks at Wilson Manifolds...
The folks at Wilson Manifolds suggested this 2-inch spacer to ride on top of the Edelbrock Super Victor manifold for this application.
Engine owner Larry Richards...
Engine owner Larry Richards beams in the background, not only because his reformed toy is about to come to life but also because his son, Curtis, is helping RJHP's shop foreman Steve Kuhls ready the motor on the dyno.
These Billet Fabrication aluminum...
These Billet Fabrication aluminum valve covers include internal tubes to carry oil to the springs and threaded fittings to make the connection to the oiling system.
The final numbers for this...
The final numbers for this pump-gas, Bow Tie-head small-block were 486 hp at 6,800 rpm, 407 lb-ft of torque at 5,200 rpm, and an average of 451 hp and 389 lb-ft between 5,600 and 6,600 rpm. CHP
Regular CHP readers may recognize Larry Richards as that guy who has been top-speed racing in Nevada at the Pony Express 100 in his immaculate '87 Monte Carlo for the past couple of years. But neither of his outings there, unfortunately, was exactly flawless.
In the '97 race, Larry had the tire pressure set too low, resulting in a high-speed blowout that also took out some of the bodywork on the right rear. In 1998, the tire pressure was carefully checked before the race, only to have the ZZ3 crate motor shatter the valvetrain after an extended period of wide-open throttle.
According to Michael "Ron" Slover, Richards' navigator, his immediate post-race investigation consisted of slightly lifting up one valve cover and peeking under it, then saying only, "Ooh, it's ugly!" before putting the valve cover right back down. The postmortem concluded that the hydraulic lifters had pumped up during the extended high-rpm exercise and provoked the inevitable carnage, which was luckily confined to shattered valvesprings and lifters.
At this point, the need for a better Pony Express engine was painfully obvious. Scrapping the hydraulic lifters was the first decision, so the step up to a mechanical roller cam was an easy one. Since there was no damage to the block, Bow Tie heads, or crank, retaining them also seemed to be the logical choice. And since this car is no trailer queen, maintaining a reliable pump-gas motor was an essential part of the equation.
When it came time to pick an engine builder to put everything back together, it didn't take long to find a volunteer. Besides being the Monte Carlo's navigator, Slover is also the in-house porting wizard at Reggie Jackson's High Performance (RJHP) in San Bruno, California. RJHP's manager and engine builder John Gianoli readily agreed to take on the Mouse motor's resurrection.
Once the wounded motor arrived at Gianoli's shop, it was dismantled and all the broken and useless pieces hit the trash can. Gianoli then decked and align-honed the block while the cylinder bores were cleaned up by 0.020 inch, just to conform to Gianoli's preferred clearances and set-up.
Gianoli consulted with Glenn Steyers of Crane Cams, who designed the roller-cam profile specifically for this application. Steyers plotted the camshaft on Crane's computer software and chose Crane's H11 tool-steel "endurance" valvesprings to avoid further problems. The cam is ground out of an 8620-steel billet with a cast-iron distributor gear pressed onto the back of the cam. This avoids the problems associated with the use of a bronze distributor gear that, according to Gianoli, would be junk within 1,500 miles.
While the machine work progressed, Slover began massaging the heads with a standard RJHP street/strip porting job. The spring seats were also machined larger to accept the endurance valvesprings (230 pounds on the seat; 610 pounds open), which have a larger diameter and different installed height than the stock springs. The heads were then stuffed with Manley severe-duty valves (2.02-inch intake; 1.60-inch exhaust) that are 0.100 inch longer than stock, with the rest of the valvetrain components (roller timing-chain set, lifters, pushrods, rocker arms, titanium retainers) also coming from Crane's catalog. The valvetrain action is hidden from view under a set of aluminum Billet Fabrication valve covers that are fitted with internal spring-oiling tubes.
Other hardware finding its way into this now-353-inch small-block came from a variety of sources. ARP provided all the fasteners used throughout, and an Aviaid oil pan covers up the bottom; an Edelbrock timing cover and Super Victor intake manifold reside out front and up top, respectively. Inside, Sportsman Racing Products (SRP) pistons and rings ride up and down on SCAT 6-inch, H-beam connecting rods.
Aside from building a reliable motor suitable for both the extended rigors of the Pony Express 100 and the daily grind of street driving, one of the theoretical goals with this project was to see if the small-block could hit 500 hp. After a fairly extensive test session on the RJHP dyno, the best numbers were 486 hp at 6,800 rpm and 409 lb-ft of torque at 5,200 rpm, utilizing Richards' original, decades-old four-barrel and a 2-inch spacer.
Naturally, we were anxious to find out how everything went in the '99 Pony Express race. We quizzed Slover when he returned to the RJHP shop after the event, but his ear-to-ear grin told the story. The motor ran cool and never missed a beat. They came in second in the 160-mph class, behind only a $200,000 twin-turbo, 190-mph-plus, European/gray-market Porsche. The only problem they encountered was that the car's handling was a bit scary on the long straight and a handful in the corners.
Richards subsequently discovered that the front end was incorrectly aligned, which accounted for the high-speed disorder. With that now literally straightened out, he confessed that he has indeed been taking it out on the streets around his town (just for testing purposes, of course), leaving plenty of slack jaws in the wake of this sleeper of a street-sweeper. And he's counting the days until the first Pony Express 100 of the new millennium.
10041 Canoga Ave.
2700 California St.
Reggie Jackson High Performance
4700 NE 11th Ave.
530 Fentress Blvd.
1960 Swarthmore Ave.
Sportsman Racing Products
15312 Connector Lane
649-F Easy Street, Dept MMFF
531 Spectrum Circle