For about the past three years, MM&FF has tackled a lot of projects using Three-Valve engines. We have made ridiculous power thanks to the latest forced induction components, as well as having some fun with the giggle gas stuff. Our staff has also beat the latest mod motor to death on chassis dynos, dragstrips, road courses, and even engine dynos, to show what the aftermarket has to offer. In reviewing some of the previous stories on the engine, we noticed a trend of working mostly with forced induction or simple bolt-ons. This month, we ventured to Livernois Motorsports and tackled a naturally aspirated buildup. We decided to swap the heads and camshafts on a stock engine, which was bolted up to Livernois' in-house engine dyno.
In stock trim, the Three-Valve engine made 313 hp and 314 lb-ft of torque. Our test engine
The latest modular engine features some interesting technology that addresses some issues of the modular line. First and foremost, the small cubes definitely hurt overall torque output. To solve the problem, without hurting high rpm power production, Ford turned to a neat trick that other manufacturers utilized in their small-sized engine packages. It's called Variable Camshaft Timing. Essentially by adjusting the cam timing, the power curve can be shifted up or down. In the past, once you set cam timing you were stuck with its results, but not anymore. The Three-Valve engines have the ability to move the camshafts while the engine is operating.
In stock trim, Ford sets up Three-Valve engines with 7-degrees advance and then retards the camshafts as the rpm powerband moves north. The computer is capable of shifting the camshaft timing as much as 60 degrees (in relation to the crankshaft). That puts camshaft timing at a total of negative 2 degrees (a total of 9 degrees retard from the initial setup). To accomplish this task, Ford uses a series of channels and reservoirs in the camshaft sprocket in order to physically move the camshaft while the engine is running. The system is a really basic concept where computer controlled valves (one for each cam) regulates the oil flowing in and through the sprocket. The rule of thumb with camshaft timing is that advancing the cam shifts the powerband to the lower rpm levels. Retarding the cam timing moves the powerband higher. Combine the new camshaft movements with a killer set of Three-Valve heads, and Ford built a modular engine that out performs the previous generation of Two-Valve mod motors and even some of the naturally aspirated Four-Valve cars.
The stock heads were removed and discarded. We reused the stock camshafts for our first te
Back in the Aug. '08 issue of MM&FF we explored the concept of limiting variable camshaft timing (VCT) in Three-Valve modular engines ("Lockdown," pg. 128). In the article, we tested Comp Cams' Phaser Limiters, which restrict the camshafts to just 20-degrees of movement. Limiting the camshafts works well, and we picked up a lot of power with our test subject, a 300ci mod motor. As with everything in this hobby, there are many different ways to get results, and Livernois Motorsports has its own version of locking down the VCT. Its engine shop has developed special inserts that completely lockout the cam timing, making it a fixed entity.
Livernois has vast experience with these engines and has chosen to completely lockout the VCT using inserts in the cam sprockets. Why would they decide to do so when it seems the system works so well, giving these Three-Valve engines both low-end grunt and top-end charge? "The main reason we prefer the full lockout method is that currently we have seen far too many issues and failures to feel comfortable with the VCT system functioning. We have seen completely stock VCT systems have issues with cam phaser failures. This is why we suggest to lockout the phaser," says head Livernois engine builder Mike Schropp.
The short-block was stock and untouched. This particular piece has been abused many times
In addition to locking out the VCT, we swapped on a new set of CNC-ported heads (done in-house at Livernois) and then upgraded to new cams with the VCT lockouts. Schropp and his staff showed off the capabilities of its parts and pieces on the in-house engine dyno. They first dyno'd a bone-stock Three-Valve engine that serves as an R&D tool. In stock trim, with just a set of long-tube Kooks headers, the engine produced 313 hp at 5,500 rpm, while torque came in at 314 lb-ft at 4,300 rpm.
Did Ford underrate the engine, since we saw 313 hp? In all fairness, the 300 number is probably close. Remember, our dyno engine wore a set of long-tube headers, which probably hurt a little in stock trim. But more importantly, we ran without the accessories like A/C, power steering, and alternator. Another deviation from stock was that this engine was run with an open throttle body thanks to the FAST XFI fuel injection system. No restrictive inlet tubes or MAF sensor to contend with, and the computer had a custom tune. The VCT was also locked out. So it was slightly better than the way Ford tests its engines.
The stock intake manifold and throttle body was used for all testing.
We chose to swap out the heads first and keep the camshafts stock. A change in bumpsticks would follow for a combined power gain. Changing heads on an engine while on the dyno is ridiculously easy. The Livernois staff worked quickly as one guy per side made the process go twice as fast. It seemed like an instant that the new heads were on the engine and the test mule was blasting through the rpm range again. The Livernois Stage 3 CNC-ported heads are available for the ripe sum of $2,899, including the cylinder head castings. Stage 3 heads are capable of flowing a max of 300 cfm through the intake ports, while the single exhaust port moves 215 cfm. Intake valves are custom units that check in at 35mm. On the exhaust, the inconel pieces are 38mm. Some pushrod enthusiasts might be wondering why the exhaust valve is bigger-it's because the intake has two 35mm valves per cylinder. It's no wonder we have seen 8-second capable Three-Valve modular engines with ported stock heads.
A 5-axis CNC machine performs its duties on the Three-Valve cylinder heads. Using a CNC ma
Adding Livernois heads to the stock short-block netted us over a 100 horsepower gain-on the engine dyno. Power shot up to 420 at 6,100 rpm while torque got a shot in the arm by going to 354 lb-ft at 5,200. As you can see, peak rpm for both torque and horsepower increased greatly. This is due to the better breathing cylinder heads, as they moved the powerband since the engine was able to breath easier in the upper rpm ranges. The engine was at the limit of the stock camshafts, and Livernois had a pair of Comp Stage 4 cams waiting to be installed to remedy the problem.
Like we mentioned earlier, Livernois prefers to completely lockout the VCT actions. A simple block that Livernois produces handles the task. "The lockouts put the cam in the neutral position. This is the position that the spring on the front of the phaser wraps the cam gear into naturally. By locking the phaser out, you have a little more control over what camshaft profile you want to run," said Scrhopp. Eliminating the VCT removes the chance of failure, and allows for a custom profile camshaft to be dialed in exactly where the engine builder wants it for max power. "The factory camshafts have a different lobe profile that allows them to work in conjuction with the phasing system. Some aftermarket cams also carry this trend but do not work as well when the camshaft is locked out. This is where coming up with a profile that fits the engine without the VCT can allow for more room in the camshaft design."
From the CNC machine room, the heads are brought to the Cylinder Head Assembly clean room.
Here is a look at the combustion chamber with its three valves per cylinder configuration.
The intake ports flow 300 cfm while the exhaust moves 215 cfm.
Naturally, Livernois-spec valvesprings are utilized in all of the cylinder heads.
The Comp Cams Stage 4 cams that were installed on the engine featured here are pretty aggressive. The cam, however, is completely street worthy. Just don't expect to claim it to be stock when you are at the street races, it is quite noticeable. The head and cam package will enable a Three-Valve engine to rev to 6,500 or so rpm, in naturally aspirated trim. Thanks to the Livernois valvesprings, achieving that type of rpm range was really easy.
Like the cylinder heads, installed camshafts with the engine out of a car made the process so much easier. In no time, the camshafts were swapped and the engine was purring on the dyno. The extra air let into the cylinders was worth a whopping 31 hp. That brought total output to a rather impressive 451 at 6,500 rpm. Torque output rose as well with a peak of 401 at 5,500 rpm.
Schropp lowers a fresh set of Livernois heads onto the engine block.
Cranking out 451 naturally aspirated horsepower at the crank is good for something in the low 12s. Those types of times would require 4.10 or 4.30 gears, super sticky rear tires, skinnies, and the usual assortment of suspension upgrades. Naturally, the driver will have to run through the gears very aggressively. Swapping to the ported heads and larger cams is something that can be accomplished with your engine still in the car. Schropp gave props to the Three-Valve engines and said they respond very well to boost. He did caution that it is easy to push the engine beyond its safe limits when power adders come into play. It just so happens that Livernois has short-blocks to go along with its induction pieces as well. Horsepower sure does come easy these days.
Stock cams were used initially with the ported heads, and then we swapped in a set of afte
After the chains have been properly reinstalled, the front engine cover is bolted back on.
Here is a computer-controlled valve that regulates the flow of oil to the cam sprocket. Oi
Dyno Test Results
Stock Three-Valve short-block
Stock: Stock heads and cams
Heads: Livernois CNC-ported Three-Valve Heads
Cam + Heads: Livernois CNC-ported heads and Comp Cams Stage 4 camshafts
|RPM||Stock HP||Heads HP||Cam + ||RPM||Stock TQ||Heads TQ||Cam + |
| ||Heads HP||Heads TQ|
Once we dyno'd the engine with the ported heads and stock cams, it was time to take off th
Here is the cam sprocket that includes a special oiling system and a huge spring. It is re
Cam caps hold the cam in place, much like a main cap on an engine block.
Comp Cams Stage 4 sticks replaced the stock units.
Livernois sells billet inserts designed to lockout the VCT.
Here is one of the reservoirs that fills up with oil in order to retard the cam timing.
The Livernois insert prevents the internals from moving, effectively locking out the VCT.
Here it is installed.
Use Loctite on the bolts when reattaching the sprocket cover.
The engine is almost ready to be retested with the Comp cams and the Livernois ported head
We were ready to dyno as the Kooks headers and EGT sensors were attached. The new heads an