We carefully disassembled...
We carefully disassembled the top of the engine (novice 'Stang techs should consult a good Ford service/repair manual like Chilton's or Haynes for guidance on how to properly take apart and put together an engine-and for the all-important torque specifications for the various bolts on the motor). Then we yanked the stock camshaft out of Fumiko Alston's '93 GT convertible and replaced it with Crane Cams' PowerMax 2020 bumpstick.
Horse Sense: Cam swappers should be aware of the importance of selecting the right camshaft. The super-lopey, high-lift cam you think is your ticket to low e.t.'s might be the very thing that makes your 'Stang even slower than it was before you made the change.
That cam sounds gooood! - is usually the unanimous statement of approval at car gatherings, the track, in the shop-pretty much anywhere-whenever the rumble of a cammed, small-block Ford is heard. Man, there's something about the lope of a hot bumpstick. The sound can make many a 'Stangbanger salivate like Pavlov's dog, and forces even novice enthusiasts to say, "Whatever's under the hood of that thing definitely isn't stock!"
Selecting and purchasing a performance camshaft are among the first internal-engine upgrades a 5.0 enthusiast makes when he embarks on the road to improving his Pony's performance. In a conventional, pushrod 5.0 engine, the cam is the long, forged-steel rod with round and egg-shaped lobes (one lobe per each valve) that runs through the center of the engine block from front to back. The camshaft's role is to actuate all the components of the valvetrain (lifters, pushrods, and rocker arms) that control the operation of the intake and exhaust valves. By opening and closing at points initiated by the camshaft's timing profile-after, and before bottom dead center and top dead center-the valves let in the air/fuel mixture and send exhaust gasses out of the combustion chamber.
Here's Crane's PowerMax 2020...
Here's Crane's PowerMax 2020 hydraulic-roller Ford camshaft. The cam sports 0.530/0.530 intake and exhaust lift, with 0.208/0.216 duration at 0.050. Hydraulic roller lifters and a billet timing gear make up the rest of our cam-swap package. Also shown are Crane Gold 1.70-ratio aluminum roller-rocker arms and chrome-moly pushrods. The rockers are a bit too big, and the pushrods too long (651/48-inch) for Red Ruby's factory-stock combination, but they'll boost the cam's 0.530 lift to 0.563 on both sides.
We wanted to see what kind of performance difference installing a good, street camshaft would make on a stock 5.0 Mustang. We also wanted to show newcomers to 'Stangbanging one of the easier bolt-on projects that can be accomplished in the driveway or home garage. Mrs. Fumiko Alston owns-yes, it's her car, not her husband's-the virgin '93 GT convertible with AOD we used for our cam swap. The 'Stang, which Fumiko affectionately calls "Red Ruby," was a daily driven, untouched ride we knew would be perfect for this project.
With Fumiko's blessing and assistance from her husband, Ward (who owns and races an '88 hatch GT in NHRA's Stock Eliminator category), we installed a PowerMax 2020 camshaft (PN 444211), hydraulic roller lifters (PN 36530-16), and a roller timing chain (PN 44975-1) package from Crane Cams we hoped would give the 'vert more zip on the freeway and put a "not-stock-anymore" burble in the exhaust note. Follow along as we take you through the project.
We saturated the new cam with...
We saturated the new cam with two tubes of engine assembly lube prior to stabbing it into the block. When installing a camshaft, do not nick or bang the cam bearings as you guide it in. Once the cam is seated, be sure it can be rotated freely by hand and doesn't bind or hang up inside the block. Brand-new Crane hydraulic-roller lifters were also added to Red Ruby's powerplant after soaking them in fresh motor oil for a few hours.
Once the camshaft was in,...
Once the camshaft was in, Crane's double-roller timing chain and billet gears were installed and the cam thrust-plate bolt was tightened to 9-12 lb-ft of torque. The actual cam timing gear gets 40-45 lb-ft of torque for a small-block Ford application. The crankshaft sprocket features three keyways that allow you to advance or retard the cam's timing by 4 crankshaft degrees, without needing offset keys or bushings. While the idea of degreeing the new cam to change the power curve was inviting, we decided it was best to heed Crane's recommendation and install the cam straight up, with the timing marks for the crank and cam gears meeting each other at 12 and 6 o'clock respectively (also called "dot-to-dot") and the piston in the No. 1 cylinder at top dead center on the compression stroke (both valves closed). If you elect to advance or retard a new cam, you might experience piston-to-valve clearance issues if your engine has domed pistons or, in the case of a stock 5.0, the cam has a ton of duration or more than 0.544 inch of lift.
After finishing our installation,...
After finishing our installation, which included adjusting the rocker arms to zero lash and reinstalling the top of the engine and its accessories (we retained the stock 1.6 ratio), the all-too-critical California Air Resources Board sticker was placed on Red Ruby's core support to let SMOG inspectors know the rumbling cam had been OK'd for use in the eco-conscious Golden State.
While changing a cam isn't that difficult on a 5.0 Mustang, there are still a few things you can do to help make things go smoothly. We recommend you try these tips.
The water pump and timing-chain...
The water pump and timing-chain cover can be unbolted and removed from the engine as one piece. This will save a few minutes when you disassemble the engine on your quest to reach the camshaft, and it also means one fewer gasket (water pump) will have to be replaced. After disconnecting the alternator, we were able to remove the alternator/smog-pump bracket as a single unit with the smog pump still attached.
Try to keep all the parts...
Try to keep all the parts that are removed during the process, organized and out of your way. Bolts, washers, clips, and such should be kept with their respective parts. Plastic zip-style baggies and a permanent marker are handy items that can be used for cataloging the many fasteners and small parts that are removed when you swap a cam...
...First-timers might also...
...First-timers might also want to mark each sensor and injector plug with an ID number or letter and write the information on a pad. Wiring harnesses almost always become tangled when they're disconnected, despite best efforts to keep them in control. Numbering the connectors can speed up the plug-and-play process when you button up everything.
Take the time to clean up...
Take the time to clean up things. There's nothing like trying to reassemble an engine with parts and bolts that still have more than 100,000 miles' worth of rust, crust, or worse. A gasket scraper (and replacement razor blades), a steel brush/wire wheel, parts-cleaning solvent and mineral spirits, and a medium-size pan will be a huge help when you start doing this kind of maintenance. If you have an air compressor, an angle grinder with the small, brown 3M abrasive discs (don't be frightened by the word "abrasive"-they're safe) works great for knocking stubborn gasket gunk from the heads, block, and intake manifold.
While our cam swap involved...
While our cam swap involved replacing 16 hydraulic-roller lifters, sometimes only a camshaft is being replaced and a full dismantling of the top of the engine (removing the lower intake) isn't necessary. Anderson Ford Motorsport makes this cool Tappet Tool (PN AF-0601) setup that makes it easy to swap a cam with the lower intake in place and lifters still in the block. The tool consists of 16 powerful magnets attached to the tips of long bolts that fit in the pushrod holes of each cylinder head. A simple tug on the bolt when it makes contact with a lifter and a wing-nut adjustment to hold the raised lifter in place are all that's necessary for keeping lifters off the cam lobes while you pull out the camshaft.
Be careful! Parts breakage...
Be careful! Parts breakage at any point of the project (especially when you're installing new stuff) can be disheartening. We were in the process of finishing up our cam swap when this 11th-hour mishap occurred. We first thought the bolt had snapped inside the intake manifold.Thankfully, it was only the ear that broke away from the thermostat housing, after we tightened the bolt a little too much. To get it out using a drill or EZ Out-or having to remove the lower manifold after everything was ready to go-would have been a depressing scenario.