Turning Wrenches
With our plan in place and the parts on hand, the Charger was pulled into the shop and the wrench-turning began. Getting in for a camshaft change requires a full teardown of the front-end of the engine, including removal of the radiator and A/C condenser, if so-equipped, and all of the front accessories. Up top, the induction is easily removed; however, removing the heads is the most involved portion of the job. Getting to the outer row of head bolts requires unbolting the headers at the collectors and alternately jacking the engine at each side to provide the required clearance. There was quite a bit of anticipation when the first head was lifted from the block, which gave us our first chance to see with what pistons the engine had been built. We weren't surprised to find Speed-Pro PN 2266 flat-tops inside-a stock-replacement forged piston which, unfortunately, carries no valve notches and rests (by specification) at 0.089 inch down the hole at TDC. While we favor the Speed-Pro PN 2355 flat-tops set at zero-deck in a performance engine, the lower-compression 2266 seems to have been the favored piston of engine rebuilders over the years. The lower-than-ideal compression ratio reinforced our decision to use the relatively short-duration Hughes 2330 camshaft.
The previous owner had rebuilt...
The previous owner had rebuilt the engine in this Charger, and we had no idea which pistons we would find inside. We had our first look inside the bores when the heads were lifted off. We found Speed-Pro PN 2266s, which seem to be in every older rebuild we tear down. Spec'd for a deck height of 0.089 inch in the hole, the slugs are low on compression and have no valve clearance notches. We weren't worried about piston-to-valve clearance with our short-duration cam, but we would have liked to have seen the pistons nearer the top of the bore. With Speed-Pro's PN 2355 flat-tops having valve notches and a much better deck height available at nearly the same price, we have to wonder what these engine builders are thinking when choosing slugs. Ours measured 0.080 inch at TDC.
We pulled out the old cam...
We pulled out the old cam and found it matched the specs of the stock 440 cam.
Our Hughes cam with 110-degree...
Our Hughes cam with 110-degree lobe separation is 5 degrees narrower than the stocker, which equates to 10 degrees at the crank. That should make for a much sharper power and torque curve. The duration at 0.050 inch is some 15 degrees longer on the intake, yet the seat timing is similar, so we should see a big improvement in output, but not much deterioration in idle. The Hughes stick has about 12 percent more lift, even with the same rocker ratio-another route to noticeable power gains.
We had the engine down to a bare short-block in about half a day. The building process began with installing the Hughes camshaft and degreeing it in. We found that the intake centerline, when installed to the "0" timing marks, was at 109.5 degrees. We wanted to install the cam advanced to ensure both a clean idle and crisp throttle response. Oddly, in moving to the "A" position on the timing gear, which should have advanced the camshaft 4 degrees, we measured the centerline at 102.5, which was much more advance than we wanted to run.
To solve the problem, the camshaft gear was drilled at the indexing pin hole, and a 2-degree bushing was installed to provide a final centerline of 107.5. It shows the importance of degreeing in the cam so the installed centerline is actually measured, rather than depending on the timing marks. We lubed and installed a set of standard hydraulic lifters, PN 2011 from PAW.
Our cylinder heads were assembled with a set of Competition Cams' PN 911 single springs installed at 1.850 inches, which gives 141 pounds seat load and 346 pounds over the nose. Under the springs, Comp's PN 4700 spring locators were used to keep the spring from walking. Up top, we reused the Comp PN 732 titanium 10-degree retainers and SuperLocks-although overkill for our application, they had been on the heads before. The heads were torqued in place on top of standard Fel-Pro PermaTorque gaskets with the original head bolts, and the manifold was installed over a Fel-Pro PN 1215 intake gasket, which blocks the exhaust crossover.
Installing the Demon carb required some clearancing of the intake manifold at the choke well to clear the secondary linkage. Additionally, since Demon does not offer a Mopar throttle linkage arm, we had to do some minor adapting in this area. We found that an AFB universal Mopar linkage arm is close, so we installed it onto the Demon carb with a slight elongation of the mounting holes and a 0.250-inch spacer at the upper mounting bolt. The factory throttle linkage and kickdown arm accepted the new induction system without modification. With our hot rod parts in place, it was just a matter of bolting the headers back up and reinstalling the front accessories and peripherals. Then we were ready to run.
Spinning The Dyno
We fired up the 440 and found the idle quality comparable to the stock 440 we had disassembled only a short time before; however, when hitting the open road, there was no resemblance to what we had started with. The difference was astounding: The 440 pulled much more strongly up through the gears, with remarkable torque and a fantastic pull of power up top where the old setup would run flat. This combo really hauled, and we knew we'd come back with a healthy report from the dyno.
The cam was degreed in for...
The cam was degreed in for an installed intake centerline of 107.5 degrees, which is 211/42 degrees advanced. We had to use an offset bushing in the cam gear to dial in the cam timing to the spec we were after.
Our heads were a set of 452s...
Our heads were a set of 452s we had used as test-and-research mules in a big-block head-port development program years ago. Fully ported and polished, the flow was well over 300 cfm, but the hours and expertise involved makes them a poor choice and nearly impossible to duplicate. With the release of numerous aftermarket aluminum replacement heads in recent years, new heads are the far better alternative.
Thermal barrier-coated and...
Thermal barrier-coated and back-cut Speed-Pro valves along with Comp's 911 springs, cups, retainers, and locks, fill out the heads. The springs were set for an installed height of 1.850 inches, providing ample spring load for the aggressive hydraulic cam.