Hydraulic lifters are self-adjusting and feature a plunger and spring combination that regulates oil pressure inside the lifter body. Solid lifters are one-piece units that don't have oil-regulating plungers or springs. The small wheels at the bottom of both types of lifters are the actual rollers. Rollers reduce cam-to-lifter friction, which helps aggressive cams reach higher speed and lift levels.
When it comes to making a choice between hydraulic-roller cams and solid-roller cams, you need to have a good idea of the usual rpm of your 'Stang's engine.
Hydraulic-roller cams are your best bet for street and moderate race applications. As we've explained in this report, there are plenty of profiles available, and custom grinds can be developed to give a 'Stang's engine a big boost in performance. Other great qualities of hydraulic camshafts are that they are low-maintenance, don't require any adjustment once set, and are quiet. Hydraulic-rollers are perfect for engines that don't see more than 6,500 rpm on a regular basis.
Although there are plenty of solid-roller setups on the street, they're more racebred than hydraulic-rollers since they're intended to support engines that spend most of their running time in the 7,000-plus-rpm range. The hardware associated with a solid-roller cam (lifters/rocker arms) is typically noisier than hydraulics. Because of the way solid cams are designed, the lifters require frequent checking and lash adjustments for proper piston-to-valve clearance, which could become a pain for engines that see a lot of street time.
Camtastic ToolsWe had to include a few cool cam-related tools in this story. While there's probably many more specialty items associated with this subject, we think this group of user-friendly equipment offers something for everyone, from do-it-yourself to master-Melvin 'Stangbangers.
Anderson Ford Motorsport makes this neat set of tappet tools (PN AF-0601) for removing camshafts in pushrod engines. The tools are installed through the pushrod holes on 5.0 engines. They raise lifters away from cam lobes and allow removal of a cam with the heads and intake manifold. | 
Those of us with more Melvinistic tendencies than others will agree that a Cam Doctor is probably one of the coolest instruments ever made. They're basically computer driven devices that can give us incredible amounts of information about cams, but engine builders and gearheads call on the Doctor to give the actual specifications of a camshaft. Sure, cam manufacturers provide the key data on the included cam cards, but the Cam Doctor provides a method of double-checking the specs, ensuring you have the camshaft you want and need for your engine. | 
We've been working with this cool digital cam-shaft-degreeing tool for a while now, and we really like it. CamLogic is a simple-to-use device that eliminates all of the manual calculation and confusing elements of degreeing process. Advancing or retarding a camshaft moves and engine's toque band by changing the timing of valve events, either in front of or behind the movement of the pistons. CamLogic is invaluable to engine builders and racers testing camshafts on an engine dyno, as it allows cam adjustments or removal without having to take the tool off the engine. |