The Holley unit bolts to the...
The Holley unit bolts to the stock location, and an eccentric on the front of the cam drives the pump.
The increase in fuel drove...
The increase in fuel drove the fuel curve to the rich side, which killed a bit of power. We believe we could have installed smaller jets in the Demon carb to lean the fuel mix, but we decided to get to the task of installing the cam instead. Our thinking was that with the cam, the engine would have more air going in and would be able to use the extra fuel.
It is necessary to remove...
It is necessary to remove the distributor and the front engine dress to get the cam out.
Next, the manifold and the...
Next, the manifold and the valve covers come off.
Cam removal also requires...
Cam removal also requires the radiator to be pulled out.
Action got underway at Crazy Horse Racing in South Amboy, New Jersey, with technician Glen Knell installing the Holley High Output pump (PN 12-289-11) and then running the Capri on the Dynojet. This pump flows 110 gallons per hour (gph) and doesn't require an adjustable fuel regulator--it's bolt on and go. Not surprisingly, the greater supply of fuel fattened the curve, and this actually hurt power. Of course, we could have jetted the carburetor differently (read: down) and leaned the fuel curve, but we decided against this knowing we'd be installing the Lunati cam a few minutes later. Odds were that the larger cam would improve airflow to compensate for the rich mixture. Horsepower was now 232.6, down from 240.
Just before this test session, we learned the stock-looking stamped steel rockers were actually 1.7:1 rockers from a Ford 460 engine. This meant the 302 had 0.471-inch lift at the valves, instead of 0.444, as it would have been with the stock 1.6 arms. That was great for power with the stock cam, but we knew the piston-to-valve clearance would be too tight if we used the Lunati cam with the 1.7s. To solve the problem, we could have installed stock 5.0 rockers, but we opted for a set of Comp Cams Magnum roller-tip rockers with a 1.6:1 ratio. The Comp rockers require a screw-in stud mount, which was supplied by the company.
The cam we selected is a new grind from Lunati (PN 510A2LUN) featuring 0.525-inch lift (at the valve with 1.6:1 rockers), and an advertised duration split of 276/284 (210/218 at 0.050 inch). The stock cam duration is advertised at 266/266. The Lunati is designed to work well in the 1,000- to 5,200-rpm range, which is perfect for this combination. Lunati also has two slightly more aggressive cams in this new 510 lineup (510A3 and 510A4), as well as a bunch of cams in the new VooDoo series. Originally, we wanted to go with a VooDoo cam, but the smallest grind has 0.541/0.549-inch lift, and we felt there might be clearance problems with the pistons and the valves considering our stock short-block. Nevertheless, we did order the VooDoo cam and will consider putting it in at a later date, after we properly take a piston-to-valve measurement.
We installed the cam in the straight-up position along with the new Lunati timing chain and the Comp rockers. All the parts went in simply, and by the end of the day we had the Capri back in place on the Dynojet.
In prior testing, the engine produced the most power with 30 degrees total ignition advance, so the timing went back to that setting. We allowed the engine to reach operating temperature, then we cut it loose. Better breathing is a wonderful thing, and the little H.O. responded by delivering 255 hp to the wheels and 302 lb-ft of torque--one for every cubic inch. That was an impres-sive gain of 22 hp and 28 lb-ft of torque at the peak. A look at the included dyno charts reveals gains of over 50 hp and over 40 lb-ft of torque.
We're having so much fun with this Capri that we'll bring it back again next month, where we'll install a set of the latest AFR 165 Comp heads. The heads feature some updates over the standard 165s, so you'll have to stay tuned for all the details.