The Engine Masters Challenge is one of the densest gatherings of engine-building knowledge you'll find anywhere. Each of our competitors have gleaned pearls of wisdom gathered over the course of years in the business. They've dealt with customers' expectations, and they've seen what works and what doesn't, and that experience represents a well of knowledge we just had to tap into this year. In between dyno runs, we asked the teams of builders to offer up a tip either directly related to building engines, or related to making sure you build the right engine. The result was a broad list of 23 tips that are applicable to everyone no matter what you're building. It's all good stuff to sit back and ponder before you dig into your next project.
...ask yourself exactly what the car will be used for...
Do The Math
Quality time spent researching and picking out the optimum engine components for your planned package is time well spent, but according to the University of North Carolina at Charlotte team, that's just the beginning of the work. "You have to eliminate any unknowns or imperfections in machining and manufacturing," team member Owen Wells explained. The real key is getting very precise on all the internal measurements and clearances, which means measuring, mic'ing and possibly grinding, machining, or polishing parts to as close to ideal fitment as possible. Differences of thousandths of an inch can be the separation between an engine that runs well and one that runs exceptional with increased power and longevity. The real goal here is minimizing the minute amounts of binding or drag that impede the reciprocating assembly from spinning in the most efficient manner possible.
Know Your Torque Specs
Torquing fasteners to the correct spec is engine building 101, but what some novice builders forget is that the torque specs that register on your wrench are strongly dependent on the conditions under which the bolt is being torqued. It's fairly common knowledge that a bolt torque into a dry hole will have a lower clamping force than one torqued with lubrication, but the issue TM Enterprises helped clarify is that clamping force can also vary greatly between different assembly lubes and oils. In a perfect world, every fastener would be measured for stretch, but in practice, Eric Simone of TM Enterprises says the key is consistency; i.e. use the same lube all the way through and know the correct compensation required for the torque values. For his purposes, Simone likes to use straight 30-weight engine oil and references old SAE charts to determine his values.
Air bubbles in the cooling system are a common problem during engine swaps or even just coolant flushes, and can be difficult to purge. That's an issue since a bubble of significant size can cause overheating problems. We've even run into this issue on the dyno a couple of times during the Engine Masters Challenge. The TNT Engineering team has a brutally simple and effective answer that will work for most cars: drill an ?-inch hole in the flat steel part of the thermostat to allow air to easily pass through, which should make burping a breeze.
Dyno It Before You Pay For It
We use dyno tuning as a tool to get the most out of our combinations in magazine testing, but Lynn Peterson of the Kustom Kemp team recommends it for a more practical business purpose: multiple levels of assurance. For example, an engine builder can spec out what should be a "450hp" component package for your engine, but don't take his word for it, insist on dyno sheets. Not only will you have proof of what your engine is capable of, it should be properly broken in and proven free of mechanical issues. From Peterson's perspective, that's also good for the engine builder since he has data to back his claims and has been given the opportunity to find unforeseen mechanical issues before the engine leaves his shop.
Timing is Everything
There's a good reason that ignition timing adjustments are the number-one thing we see competitors make to their engines on the dyno at the Engine Masters Challenge; there's significant power and performance to be gained or lost by making sure the spark hits at just the right time. And the more aggressive the combination, the more true that becomes. Jon Kaase of Jon Kaase Racing Engines says it makes the most difference in how his engines perform. As a matter of fact, that's usually the only adjustment we see Kaase making during the EMC unless a problem is suspected. As a practical tip, Kaase says that if you're running a cam with a lot of duration, increase the advance timing to help improve idle quality.
Know Your Date Codes
The aftermarket is full of better-than-OEM parts for vintage engines, but there are many applications where stock-style original parts are used instead. There's nothing wrong with that, but the RM Competition team cautions that you need to know the date code of the parts you use and what the specs are. For example, timing chain sets on many engine families changed a great deal during the smog era to favor emissions rather than power. The big-block Ford illustrates this perfectly: builders should make sure that if they use a stock timing gearset that it's a pre-'72 date code. That's because post 1972 the keyway on the bottom gear is in a different position that retards the timing 8 degrees from the factory. Similarly, cylinder head combustion chambers were also altered during the '70s to less power-producing designs.
Take the Time to Degree
Modern performance cams are manufactured wwwith such high precision you can install them on the stock timing marks without any further checking and continue on your way, but Ray Clayton of Ray's Dyno & Machine always takes the time to degree a cam to ensure it's installed accurately. Clayton says it's not uncommon for timing marks to be off by a degree or two, and that's more than enough to affect the engine's power output.
Drop The Drag
KMF's tip for optimizing any engine is: "Don't try to make more power, try to lose less of it." One of the ways to do that is to cut down on the friction the rotating assembly sees. Good oil with high-zinc content such as those available from AMSOIL will help things slide, but on the mechanical side look for ways to create less contact surface area. If your engine still uses thick, old-style conventional piston rings, look into modern piston forgings designed for low-tension rings, which are thinner and exert less pressure against cylinder walls. Less pressure means less drag. Coatings on some components can help as well; KMF prefers to hard anodize their ring lands. In some applications, such as in EMC, KMF will also cut down the bearing size where possible to minimize the surface area.
More Horsepower Per CFM
On the extreme end of racing engines, like those Race Car Service of America (RCS) typically turns out, Ron Stanislawczyk of RCS says that his goal is always to make as much horsepower from every cfm of air entering the engine as possible. That sounds like a no-brainer, but what Stanislawczyk is saying is that it's not always the parts choice that affects an engine's power output, it's how it manages the air that enters it. For example, Stanislawczyk says that by managing the airflow through one of GM's popular 604-series circle-track crate engines, he can typically create about 60 more horsepower while not increasing the amount of air ingested. Removing wasted space is the key to motivating lazy air and maximizing port velocity. Stanislawczyk will actually decrease the runner size by 10 cc or so to increase air speed. Similarly, he may alter the intake manifold runners to eliminate any possible spots of stagnant air.
Match Your Angles
Barry Robotnick of Survival Motorsports has heard all of the jokes about what "FE" stands for on his favorite Ford engines. "Finally Extinct" is our favorite. FEs have a unique intake manifold that places the outer edge under the valve covers. The issue that commonly occurs here, Robotnick says, is that the angles between the intake and the heads are often a little off, especially when using modern aftermarket parts on old blocks that have been rebuilt at some point, which will cause vacuum and/or oil leaks. During the machining portion of the build, make sure your builder compares the two before assembly. This tip actually applies broadly to other antique V-8 engines since the old, low-performance tolerances tend to be all over the place. In general, it's a good idea to have any V-8 older than the mid 1960s checked for squareness during the machining stage. We can personally attest that '50s Buick nailheads are notorious for being very out of square.
Keep it Clean
They say cleanliness is next to godliness, and Bradley Nagel of Bradley Built Engines concurs. One of the biggest mistakes he sees many beginner builders make is to underestimate the importance of keeping your engine-building space as clean and dust-free as possible. Ideally, a "clean room" of some sort should be established for final assembly. Nagel says, any work that results in removal of metal (filing, grinding, machining) should be done in a separate room from where you intend to assemble because transference of material is so difficult to control. As a matter of fact, Nagel recommends doing the dirty work on separate days from the actual assembly. That's because you may be able to clean the parts, but you won't be able to get everything off of you and your clothes. All it takes is one shaving to cause damage. Also, never assume any part is clean straight out of the box. Don't open boxes in your clean room and clean everything you pull out of them prior to taking them into the clean room.