Life With a Cammed SBF FOXBODY Mustang 5.0 - What You Need To Know!
Real-World Camshaft Experience: The Ups and Downs of a Camed 5.0 Fox Body
Today, we're diving into the world of camshafts and talking about my real-world experiences with a cammed-up 5.0 Fox Body Mustang. If you're thinking about going down this road or are just curious about the potential pitfalls, this blog post is for you.
A Quick Recap: My Camshaft Journey
You might remember I did a video a while ago about the cam I chose for my ‘92 Fox Body Coupe. If you haven't seen it, be sure to check it out before continuing, as it’s a bit of a prequel to today’s topic. In that video, I talked about my decision to go with the Comp Cam XE 266 HR. I was excited about all the perks a cam can offer: more power, that iconic lumpy idle, and an overall more aggressive sound. But, like any modification, there are always trade-offs.
I was focused on maintaining as much of the stock 5.0’s low-end torque as possible, and the XE 266 HR was a great balance for that. It’s got a good torque curve that starts delivering power at lower RPMs, which is perfect for Sunday cruising and daily driving. But what I didn’t fully expect were the quirks that come with a camshaft, especially when it comes to the temperamental nature of a cammed small-block Ford.
Fast forward to today. I’m prepping to swap the top end on my ‘91 Convertible 5.0, and as I research cams for that project, I’ve been reminded of the issues I ran into with the 1992 Notchback 5.0. So, I wanted to share my thoughts and experiences with you all, especially if you’re considering going down the road of installing a cam your SBF.
The Good: Lumpy Idle and More Power
Let’s start with the positives. There’s something undeniably awesome about a cammed-up 5.0. The lumpy idle you get with a cam is definitely hard to beat - Especially on a cold start - and as it warms up, that idle just gets lumpier!
In my case, the Comp Cam XE 266 HR has provided a great balance. I wanted to keep the torque curve as low and close to stock as possible, and this cam delivers that. With the right tuning and setup, it can make power from around 1,500 RPM all the way up to 5800-6000 RPM, which is where you spend most of your time driving anyway. It’s not all about peak power at the top end - especially if your car is mainly used for cruising; it’s about driving enjoyment, and this cam strikes that balance well.
The Not-So-Good: The Quirks and Pitfalls
As with all things in life, there are a few downsides. And if you’re considering camming your 5.0, you’ll want to know about them before you take the plunge:
1. Idle Struggles and Vacuum Issues
One of the biggest things to consider when you install a cam is how it affects the engine’s ability to create vacuum at low RPM. A cam with more lift and duration (like the XE 266 HR) reduces the amount of vacuum your engine generates, which can cause all sorts of weird behavior—especially at low RPMs.
This reduction in vacuum affects idle stability. The car might struggle to find its idle after coming to a stop, and in some cases, it might even feel like it wants to stall. If you’ve ever driven a cammed car in tight spaces—say, parking lots or moving in and out of a driveway—you know the feeling. The RPMs can drop low quickly causing the engine to bog down or stumble, and if you're not careful, it might stall completely. This is particularly frustrating when you're maneuvering around a parking lot, stopping at a red light, or leaving a cars and coffee where everyone is watching…
2. The Clutch Dance: A Bit More Finesse Needed
Compared to a stock Fox Body, a cammed 5.0 requires more “clutchwork” and two quick feet! Stock, the 5.0 is easy to drive, and the engine’s powerband is very forgiving. But with a cam, especially one like the XE 266 HR, you’ll need to be more mindful of your RPMs.
In fact, you may find yourself needing to “feather” the gas to keep things from getting too jerky or even stalling. This makes driving in tight spots or low-speed maneuvers a bit trickier. It’s not the end of the world, but it does require a little more attention and finesse than driving a stock car. You can't just pop the clutch and go—you’ve got to know how to modulate it.
Is It Worth It?
So, is the cam worth the hassle? Absolutely. A cammed-up 5.0 sounds amazing, makes more power, and is a ton of fun to drive. But these little quirks are something you should be aware of and may even be a deal breaker for you. If you’re not prepared for it, a cammed car can make you look like a rookie driver; and can be especially bad if you hand the keys to someone else who isn’t used to the nuances of a cammed car.
Final Thoughts
If you're considering putting a cam in your SBF Fox Body, remember that while you'll get that awesome sound and extra power, you might also get a few headaches with idle and low-speed drivability. But if you're aware of these challenges going in, you'll be better prepared to deal with them if/when they pop up.
At the end of the day, it’s all about what you’re looking to get out of your car. If you love that old-school Mustang rumble and the thrill of extra power, then a cam is definitely worth considering. Just be ready for the odd time when your car doesn’t behave exactly how it did when it was stock.
Gary
KASL Customs
*The car being discussed has been professionally dyno tuned. With out a professional tune, the symptoms explained above can be even more pronounced