A camshaft’s role in the engine is to act as something of a brain. It’s responsible for how much air and fuel enters and exits the combustion chamber for a given amount of time. Without the camshaft, an engine simply wouldn’t run. The profile of the camshaft dictates the performance capabilities of the engine. And so, picking the right one for the job can be a bit tricky. Luckily, one particular company has been in the business of developing camshafts since the late ‘70s. And since then, they’ve produced hundreds of camshafts for just about any domestic application regardless of the intended purposes. Meet the COMP Cams XFI camshaft, one of their latest designs in an already-impressive lineup.
Xtreme Fuel Injection (XFI)
XFI stands for Xtreme Fuel Injection. These camshafts are hydraulic roller type cams aimed specifically at fuel injected engines. For a refresher, roller lifters have a few advantages over flat tappet designs. One in particular is that they allow for a much more aggressive lobe profile. This, in combination with the exceptionally wide lobe separation angle on this line of cams, makes for major gains in response and performance. COMP Cams has these camshafts ground to perform on a street performance level, along with mid-range power and (of course) top end as well. This makes it easy for any builder to take advantage of the camshaft, whether it’s on the street or the track.
This isn’t the first line of hydraulic roller cams COMP has introduced, but they are distinguished from the others. We all know that camshafts can only do so much on their own. That’s why COMP Cams designed these cams to work in conjunction with some other valve train modifications, aimed at the same engine platforms. To get the best performance out of these camshafts, COMP recommends the use of their EFI cylinder heads and intake manifolds. Additionally, they suggest that the engine uses bee hive valve springs and the Pro Magnum increased ratio rocker arms. Doing so will give the engine all the tools it needs to put the cam profile to use.
Roller vs Flat Tappet Cams
Roller camshafts have been around for a long time. Some of the engines for which these XFI cams are available, already come equipped with roller cams. Others are set up from the factory with flat tappet cams. As we said, roller cams can have more aggressive angles on their lobes; this is because of roller lifters. With flat tappet camshafts, if the grind is too aggressive, the edge of the lifter itself would dig into the lobe of the cam. Roller lifters don’t have that problem. This means that even with the same amount of lift, roller cams can have much longer duration than flat tappet cams.
The XFI grind uses wider lobe separation angles so they can keep duration without overlap. But one thing to keep in mind is that flat tappet cams are ground in a way to keep the cam still as it rotates. Roller cams are not designed like this. Therefore, when installing a roller cam, a cam plate will have to be installed to keep it from moving back and forth.
As for real world performance, the COMP Cams CFI camshafts are on the more aggressive side. They do have street grinds available but they will be less practical than other choices, and aren’t recommended for the faint of heart. This camshaft is available for Ford small block platforms along with Chevy’s LS, LT, and small block engines. They are an excellent choice for late model builds, along with engines that still utilize fuel injection fuel delivery systems. These cams can be purchased individually and will run right around the $300 mark at retail cost. COMP Cams has always done an excellent job of catering to customers’ needs, so they also offer complete kits featuring this camshaft. Those will run around $800 at retail, but everything you need is right there for you.