Improving Engine Performance - More Power For Less Money

Yes, we all know the famous saying usually credited to the great Smokey Yunick that goes something like, "Speed costs money, so how fast do you want to go?"

And in many cases, it's perfectly true. But the other side of the coin is that Smokey, like many other successful racers, was also very imaginative and found ways to tweak nearly every part on every car he raced. No matter what you race, there is almost always a way to inventively squeak out just a little more performance-especially when it comes to the engine. And very often these tweaks aren't all that expensive. To give you a head start, we've put together a list of 10 ideas to get more power from your engine, and each will cost less than a grand. In fact, it is possible to do most of the work yourself, with the possible exception of rolling the cylinder heads, and you can do the entire list for under a grand.

This list is only intended to get you thinking. It is possible that you already take advantage of some of the power-ups, and it's also quite likely that a few are illegal in your class. Use what you can-or what you think you can get by with-and come up with some more of your own. Are there any good ones we've missed? Send us a letter to share the wealth.

Advance Curves
A mechanical timing advance system is standard issue in carbureted street engines, but the majority of racers have locked out the advance mechanism in their distributors for fear of a failure. A mechanical advance, with its weights and springs and pivots, requires at least a regular visual inspection, but it really is no more finicky than anything else on your race car, and it can potentially help you make more power down low.

The purpose of the advance is to allow you to set your timing at a point where the engine will run well lower in the rpm range and then automatically advance the timing as the rpm levels increase so that the ignition timing always stays optimized. For many racers, the rpm range on the track is always above the point that the advance is fully engaged. But if you stall your engine on the track, a hot race engine will be much easier to start with the timing pulled back a few degrees by a functioning advance mechanism. It can also help you increase low-end power if you lug the engine on restarts. Companies that specialize in performance ignitions, such as Performance Distributors, can actually tune the advance curve to your engine package and help you determine if running a mechanical advance will help your performance on the track.

Oil Control
Oil is critical for protecting your engine, but it often can get in the way of making power. In top-level racing series, engine builders spend much of their time trying to get the minimal amount of oil where it needs to be (rod and main bearings, rockers, lifters, and so on) and then getting it out of the way. Excess oil, or oil that is too viscous, creates windage and is a drain on the engine.

The first thing you need to do is make sure you are using a high-grade synthetic that is the correct viscosity for your needs. Many engine builders know what works best in their engines from years of research, but if you race a crate engine or build your own, try contacting an oil manufacturer for a little help. Companies that specialize in high-performance racing lubricants have tech departments set up for helping guys like us.

Once you have the correct synthetic oil, make sure you aren't running more oil pressure than necessary. For years, a high-volume oil pump was considered a standard performance upgrade. But in a stock car racing engine that is designed to operate at high rpm levels, this often isn't necessary. A well-built engine with good bearing tolerances should function quite well with 50 pounds of pressure. At high rpm, a standard oil pump will provide plenty of pressure at speed, and a high-pressure pump will only kill power by making the engine work too hard.

Finally, even if you aren't an engine builder, you can make one simple engine modification to free up a little power. Stock engines are designed with a few oil drain back holes in the center of the lifter valley. This, however, drains oil right onto the camshaft and crank, which gets slung around and causes windage. Purchase a set of lifter valley standpipes (Comp Cams sells a set for $35) and install them in the drain back holes. The standpipes allow the pressure to equalize between the crankcase and the lifter valley while preventing oil from dripping through. The oil must drain to the pan through the larger holes in the front and back of the lifter valley. It can drain straight to the oil pan without hitting any other moving parts.

Less Bearing
You've probably heard about running a crank and rods with smaller journals to free up power. This works because the smaller journal diameter requires less bearing speed, which means less friction. This falls out of our range of cheap power enhancements because it requires a specialized crank and a new set of rods.

But that's not the only way you can free up power with the rod bearings. Standard bearing sets are normally a bit wider than necessary, and you can cut friction by reducing the bearing's surface area. Smart engine builders do this by cutting a wider chamfer area on each side of the bearing in a lathe. This requires a little work because you have to either find or cut a piece of round stock that has the inside diameter (ID) of the bearing and chuck it up in the lathe. Then clamp the bearing around the round stock so that you can cut it.

Electric Power Equals Horsepower
Make sure your engine is getting at least the 12 volts it is designed to run on. Stock HEIs (high-energy ignitions) are notorious for not being able to produce enough power at high rpm levels. If you are racing with an HEI, consider an aftermarket unit built for performance or an upgrade module made to fit inside stock units. A poorly functioning alternator can also cause this problem. If you aren't getting enough power to your plugs, the engine will develop a high-speed miss and horsepower will suffer.