Muscle Mustangs & Fast Fords
Ford 5.0 Engine Build - Bolt-Up 5.0 power
Have It Pro Built, Or Bolt It Together At Home.
Our bolt-together 5.0 power project is being assembled by a group of students from the University of North Carolina at Charlotte's motorsports program, who put together a 5.0 using a set of ported aluminum heads with 1.94/1.60 valves. The idea was to use these heads and, with the help of the good guys at D.S.S., build a long-rod street motor using the company's billet lightweight 5.4-inch rods. With a 270/280 Comp Xtreme flat-tappet hydraulic cam and an 11:1 compression ratio, this test engine made 370 lb-ft and about 415 hp. There was, however, a lot of engine-component prep, such as porting the heads, which could be done at UNCC but not necessarily by most guys in the garage at home.
The long-block for our project was essentially the same D.S.S. block as was used with our initial build. All that was done here was to strip and clean the entire bottom-end parts. To save money, the D.S.S. main girdle and windage tray were left out of the build this time around. This may have cost us a little top-end power, but it was accepted as a casualty of cost cutting. Except for the deleted windage tray, everything else went together as per the original build, including the Calico coated D.S.S. pistons, and Total Seal rings along with Calico coated rod and main bearings.
Upon inspection, the Total Seal rings from the previous build had worn no more than whatever it took to break them in. This being the case, they went straight back in the bores from which they originally came. On the front of the crank, which was the earlier and sturdier 28 oz/inch item, a D.S.S. Power Bond crank damper was installed.
From the previous episode of our D.S.S. long-rod build, it was shown that for a shorter-period cam, a flat-tappet design can actually deliver more area under the curve. The point where a roller's area superiority takes over is about 275 degrees of seat timing. In this bolt-it-together phase of our build, we wanted to be a little more traditional in terms of a 5.0 cam selection. This meant using a hydraulic roller.
Allowing the fact that this had to be a totally streetable motor meant we had better not go overboard on duration. With this in mind, a search was made through Comp Cams' hydraulic roller profiles. Throwing everything into the equation, including the flow characteristics of the heads to be used and the need for respectably high lift, resulted in the selection of the intake and exhaust profiles. The intake profile was 280 degrees of off-the-seat duration and 284 on the exhaust. Both were 224 degrees at 0.050 inch. Another consideration was that the intent was to run with the springs the heads came with. This meant the agenda included investigating profiles that were easier on the valvetrain than, say, Comp's Xtreme series. With the 1.6:1-ratio Crane rockers, which actually measure out closer to 1.65, the measured lift came to 0.575 on the intake and 0.545 on the exhaust.
With the profiles selected, we went ahead and ordered our cam, which was to be ground on a 110-degree LCA with 4 degrees advance, together with lifters and a new spider and dog bones.
Timing the Cam
Having diligently selected a cam that is essentially a known performer, it makes sense to time it so that it actually delivers the intended valve event timing. Another factor you should know is that a cam with too much retard has more negative impact on the power curve than one with too much advance. We had to shoot for 4 degrees advance, but 5 or 6 would still be OK, whereas 3 would not. To achieve the desired timing, we used Comp's nine-keyway sprocket set. This gave us the ability to adjust in 2-degree increments. By using this timing set, the called-for 106-degree intake centerline timing was precisely achieved. At this point, the valvetrain for the No. 1 cylinder was assembled, as was the optimum pushrod length to produce a centrally placed sweep over the valve tip. With that knowledge, a call was put into Comp to ship us the requested length.
The next valvetrain item we need to talk about is the rockers. Crane rockers were selected because our own tests had shown they had the geometry to lift the valves a little quicker off the seat than most others out there. This is important. Remember, we are now using a roller cam, which has less acceleration in the first 7-10 degrees than a flat tappet. This is the downside of a roller, but it can be compensated for in part by making an informed choice when it comes to rockers. Crane 1.7:1 rockers were considered here as we are looking for all the lift possible, but they would have put the system dangerously close to spring-coil bind. Our second choice was the 1.6, and this is what we went with.
Heads and Intake
Obviously, before the top half of the valvetrain could be installed, the heads had to go on. We used Edelbrock Performer RPM heads, and the justification for using these is covered in detail in the "Cylinder Heads" sidebar. As usual, our head gaskets of choice were from Fel-Pro, as were all the other gaskets. As with our previous build, the intake chosen was an Edelbrock Performer RPM Air Gap. It delivers the bottom end Edelbrock says it will, but given enough carb capacity, much more top-end output and rpm than the company claims. Based on our dyno testing, our recom-mendations for carburetion are a 650 for cams up to about 275 degrees duration and a 700-750 for 280 or more.
Remember, before you take these recom-mendations as being universal, they apply to a dual-plane intake, which has substantially different requirements than a single-plane unit. For carburetion, we started the ball rolling with our trusty 750 vacuum secondary Road Demon from Barry Grant. As you can see from the lead shot of the finished engine, the induction system was complemented by an AED throttle linkage and bracket. If you want to really spoil yourself and get a smart, functional, throttle linkage into the bargain, this is what you should use.
In most cases, if we see the opportunity to make life simpler and still achieve the goals at hand, we take that route. Using a Performance Distributors, Ford-adapted, GM H.E.I. does just that. These distributors come from Performance Distributors with a custom advance curve that is just right for the job. In addition, it is capable of delivering a race-intensity spark to about 9,000 rpm in a manner as precise as we would all like. Lastly, and probably most importantly, it's a one-wire hook-up deal. Just connect the red wire to 12V on the positive side and your entire ignition system is ready to go. Now how simple can that be?
As for plug cables, we usually use Accel's bright-yellow wire wind 8mm race stuff. When our engine builder, Mike Keena-Levin, got around to the plug-to-distributor wiring, it was found we had only the Accel super-high-temperature heat-resistant, black cables in our stock of parts. Now you may well ask where the snag is here-that is, if you even thought there was one. The truth is that Accel's yellow cables are more than up to the job-and are photogenic, to boot. Our Accel high-temperature black cables are known to do a great job on the dyno. Here, the exhaust heat is far more destructive to plug boots than when the engine is installed in a car. If your budget allows, consider running these high-temperature Accel cables, especially if you have headers really close to the boots. In all other cases, I would say save yourself some money and use the Accel wire wound yellow (or red) cables.
Any 5.0 Ford application could end up with one of two water pumps, these being the forward and reverse rotation items. Since we're never sure of the ultimate application of our project engines, life normally gets a lot simpler by dynoing with an electric water pump. Not only is this simpler for the test installation but, in most cases, there is horsepower to be had, as mechanical water pumps can absorb up to as much as 10 hp. As you can see from our lead shot, we have a CSI pump installed.
As one might expect, Keena-Levin was really looking forward to dynoing the finished project engine. We were now in the new UNCC Motor-sports building, which has a dual-installation dyno cell. This was looking really good, and the gleaming 901 Superflow dyno was nearly ready to do battle with our engine. It all looked so photogenic, unfortunately one small, but highly significant detail, was to be our undoing here. The water supply to the dyno cell proved to be too small, and a new, bigger system could not be installed in time to meet editorial deadlines. This caused something of a panic. Although we know plenty of people who have dynos, they are all busy doing race-car stuff (Charlotte is Cup Car country central). In addition to availability, we also needed a bigger-than-average dyno cell that was light and photo friendly (most are not).
Here is where what could have been a bleak situation reversed direction. Your author knew that his friend Lloyd McCleary, Busch engine builder (he has had as many as 25 engines in one Busch race) and boss at T&L had just the photo-friendly cell (three, to be precise) we were looking for, but is usually too heavily booked for an immediate test session. Well, we got lucky. When we called, McCleary said to "be here Saturday morning at 11 a.m. We can run your engine 'til 4 p.m., but you must be out by 5." That may sound like a high-speed deal where it leaves us little time to do much, but McCleary's shop is geared to dyno a lot of engines. He sometimes has four engines through a cell in one day.
We arrived at T&L at 10:30 a.m., and by 11:00 we were wheeling the engine into the cell. About 20 minutes later, the engine was on and the Kooks headers were installed. The only problem we ran into was that the CSI electric pump was not instantly compatible with the hose arrangement on the dyno. Rather than spend time heading off to hunt down parts, we elected to swap out the CSI pump for a mechanical one McCleary had on hand. With that done, we were ready to go.
By 12:15 the engine was primed and ready to start. The BG Demon was given a half-dozen stabs to put fuel from the accelerator pump into an otherwise-dry manifold, and the starter was hit. After a couple of revolutions, the fuel hit the cylinders and the engine roared to life. Timing was set to about 5 degrees less than was expected to be finally used, and the break-in was carried out. Because of time constraints, it would have to be a short break-in, and we would have to forego an oil change to a more powerful synthetic like Mobil 1 or Joe Gibbs Racing's new synthetic race oil.
While the engine was breaking in, McCleary asked what the engine spec was. We told him what was contained within and that, with a few minor variations, it was essentially a D.S.S. build that we had done. "Well, those guys at D.S.S. must have a good handle on things" he said. "We build a crate-motor spec for those race customers of ours who want a reliable street motor, and it is really close to that. If you guys have done a good job, you should see better than 370 lb-ft and 375 hp. If you are really on the ball, it should better 380 lb-ft and go right around 400 hp."
After only a 20-minute break-in, our first pull was done, and a huge miss instantly made itself apparent. Pulling the plugs revealed two cylinders were running unbelievably rich. This led us to suspect a blocked jet. A subsequent rebuild of the carb revealed debris probably acquired during our move into the new shop at UNCC, but we had no time to do a rebuild. McCleary had a number of Demon carbs on hand, so we grabbed the first-available photo-perfect 750 off the bench and bolted that dude on. Things got better, but it was still way too rich. We were about to go into it when McCleary remembered it was a customer's carb and had been set up a day or two before on a 550hp-or-so 383-inch engine. The next carb was one of McCleary's dyno specials (i.e., it never goes on a car). It was ugly from extensive use but had been on an engine that McCleary thought might not be too far off from what we wanted. Time was ticking away, and it was not until about 3:30 that we got to do the first real pull.
The carb was close but not spot on. The engine made all the right noises on this pull and cranked out 378 hp along with 367 lb-ft-not bad for only 24 degrees of total timing. Now before you go thinking we should have set the timing at 34 degrees right off the bat, remember that one of the reasons the Edelbrock heads were used is that they have good swirl. This means a faster burn and, as such, less timing is needed to get the job done. Previous experience with heads having adequate swirl have shown they rarely need more than 29-30 degrees of total timing to maximize the horsepower. For the next pull, we ran 26 degrees, and output jumped by 12-some-odd horsepower and 14 lb-ft. This prompted going to 28 degrees total timing advance. The result was 385 lb-ft, 395 hp, and our deadline of 4 o'clock all at the same time.
Achieving 400 hp would have been nice, but no one was disappointed. Why? Because it was pretty much certain that another degree or so of timing would have netted a couple of horsepower as would the change to a synthetic oil. On top of that, a look at the plugs indicted some minor jetting changes would also have helped to an estimated tune of 3-4 hp. Given all these factors and a longer break-in, it looked fairly certain that this engine would have topped about 403 hp. As for it's streetability, we found that the dyno, which was set up for high-rpm race engines, would not lug our 5.0 down lower than 2,200 rpm because of its strong, low-speed torque. At 2,200 it showed a steady state 289 lb-ft. That's more than a stock 5.0 peaks out at.
At the end of the day, we think we can say that not only did we get a good-looking engine, but also a cost-effective one that met all our needs for a true street machine as well as high performance on the track.
The choice of heads for our project engine was not something that came about simply by hunting through catalogs. The UNC Charlotte flow bench was put to good use, and the results of many (but not all) of the popularly used heads were compared. One factor that played a strong role was the out-of-the-box flow-bench performance in relation to price. Here, the Edelbrock Performer RPM heads scored well. Not only did they closely replicate the flow figures of our smaller valved but ported Windsor Jr. Lites from World, but they also delivered some of the highest swirl numbers of any 20-degree Ford head. All these assets made them look good for our purposes.
A check with a few well-known engine builders who have great experience with a wide variety of heads sealed the deal, and a set was duly obtained from Edelbrock. The fact that the heads have high swirl means that better low-speed output is likely. This in turn allows a slightly larger cam to be used without the low-speed output becoming unacceptably low for the street. In practice, we found we could use a 280-degree-seat duration cam and still come up with a better low-speed output than an otherwise stock engine with a much smaller cam.