Most car enthusiasts agree: the #1 sought-after performance modification is to your vehicle's engine. Everyone loves the idea of more get-up-and-go to scoot you down the road (or track) that much more quickly. Oversize pistons, hotter cams, bigger carburetors, and add-on turbochargers and superchargers are just some of the time-honored ways to squeeze more power from your mill. At the high end of the price spectrum, crate engines give you an immediate boost in size and power, and look sharp too.
While we all lust after more ponies, the problem for many is the cost of those ponies. Engine block boring, major overhauls, high-end componentry and complete engines all come at a price, and for those of us without unlimited bank accounts, the associated price tags tend to cause us to conclude that engine mods are outside our budget and therefore off the table.
But we at CARiD have good news! It doesn't need to be that way at all. There are a number of modifications available within our Engine Performance Department which will gain you some additional horsepower, and which can be installed by weekend warriors who like to turn their own wrenches (the DIY set, in other words).
What follows are six of our favorite engine mods, all found in our online store. As you go through each one, note their affordability and ease of installation, at least compared to pulling and disassembling the engine! Also note that related upgrades to air intake, fuel, and exhaust systems are not included here, as they reside in their own categories, and we will be covering those performance upgrades in future articles.
Deep Sump Oil Pans
Engine oil is the lifeblood of your vehicle's motor, and its primary purpose is to lubricate all the moving internal parts. But did you know that engine oil also plays a critical role in engine cooling? Of course, the fluid in the car's radiator, which circulates throughout the block and head, is the primary means by which engine heat is carried away. Engine oil contributes by also absorbing heat and then dissipating it during circulation.
It stands to reason, then, that if we add more oil to the circulation, we can carry away more heat. A cooler engine is a more efficient engine, and it's one that can be driven more aggressively without inflicting heat-related damage to it. However, this does NOT mean that you should go out and simply add an extra quart to the crankcase! Overfilling an engine beyond the 'full' mark on the dipstick can cause the oil to foam, which leads to poor circulation. It also can cause an engine to burn oil. Instead, if we increase the size of the oil pan (the sump), we effectively increase capacity without any downsides. Many of these deep-sump oil pans add ribs which increase the surface area and help keep the oil cool.
If the new pan's material is aluminum, we also stand to gain via weight savings. While stamped steel oil pans are not heavy by design, the idea of a larger pan, along with another quart or two of oil, does create a weight penalty. Selecting a pan made of lighter weight material helps to offset that weight gain.
On many cars, replacing the oil pan is simple enough: drain the sump, undo all the oil pan bolts, drop the pan, and bolt up the new one, always using a new gasket. On other vehicles, the job might be somewhat more involved if it involves loosening the front crossmember, or possibly raising the engine a bit. While the installation time increases, it still should be within the capabilities of most weekend mechanics. As a reminder, be careful of ground clearance, especially if your vehicle is lowered.
There are several designs we like, including this pan from aFe Power, available in natural or black finishes, as well as this one from PPE. And let's not forget to add that when peering under the front of the car, both these pans add a little bling to the usual murky appearance under there.
Engine Oil Coolers
Now that you've seen the advantages of lower temperature engine oil, you have options in addition to replacing the sump pan. An auxiliary oil cooler works just like your car's radiator, except it's engine oil rather than antifreeze being circulated. As long as the oil cooler is positioned where ambient air can pass through it, it will shed heat from the oil before it circles back into your engine.
Installation is not difficult, but make sure there's an appropriate location near the front of the engine compartment to mount it. Oil cooler kits also include the necessary hoses to connect to the block, and you'll want to make certain that there's room for those too.
Hayden, a well-known name in engine cooling componentry, makes a number of different all-inclusive oil cooler kits for a variety of late model vehicles.
Mishimoto, another big company in the engine cooling arena, makes what they advertise as direct-fit kits which can lower engine oil temps by up to 20 degrees.
Adjustable Cam Gears
An engine's camshaft (or camshafts) controls valve timing by determining with great precision the exact moments when intake and exhaust valves open and close. While factory settings are designed to provide the optimum compromise among power, fuel economy, and emissions, changes to valve timing can provide performance payoffs. It has been customary to install performance camshafts to alter valve timings. "Custom cam grinds" can customize cam lobe size and placement to increase both torque and horsepower. However, custom camshafts are not inexpensive, and installation can become involved.
In recent years, clever engineers realized that valve timing can be altered in another way. On overhead camshaft (OHC) engines, a timing belt or timing chain runs from the crankshaft up to the cams. The belt or chain engages gears mounted to the front of the cams. If the camshaft timing gear itself can be made adjustable, then valve timing can be tweaked without resorting to more expensive or time-consuming mods.
Are you capable of replacing your own timing belt? If you are, then installing a set of adjustable timing gears should be well within your skill set. If your engine runs a timing chain, the work is a bit more involved, but at least it can be done with the engine remaining in place. Be prepared to set aside most of a weekend to get it done.
Examples include these adjustable gears from HKS, designed to fit many Asian cars from the 1990s, and the Skunk2 pro series adjustable gears, designed for Honda and Acura automobiles.
Underdrive Pulley Sets
No matter how much power an engine produces, there are so-called parasitic losses caused by drag on the engine. Common accessories such as air conditioning compressors, power steering pumps, and alternators are belt-driven and consume some power that could otherwise be put to the driving wheels. The aftermarket, looking for more power, sought ways to reduce parasitic losses and gain what amounts to "free" horsepower. The belt-driven accessories became an area of focus and lead to the development of underdrive pullies.
An underdrive pulley has a smaller diameter than a stock pulley. The advantage is that belt-driven accessories run more slowly, which reduces parasitic drag and actually ups the horsepower. One manufacturer quotes HP and torque gains of 11 and 7 respectively. Testing is done to ensure that the accessories do not turn so slowly as to impede their own job. Depending on the manufacturer, the aftermarket may offer a single underdrive pulley for the crank, or a set of pulleys for all the engine's belt-driven accessories. Along the same lines, if your motor is already running a supercharger, an overdrive pulley, such as this one from Livernois Motorsports, can drive your supercharger faster and give you a nice power bump.
The installation of underdrive pullies can be done with the engine in place. Depending on the year, make, and model of your vehicle, the biggest challenge may simply be one of access, given the crowdedness of modern engine compartments. While you're at it, be sure to check the condition of the drive belts themselves, and replace them if any look worn, frayed, or cracked.
The BBK underdrive pulley system is available to fit a variety of recent domestic vehicles; the Dinan brand underdrive pulley fits popular BMW models.
Performance Harmonic Balancers
An often-overlooked part of an engine's rotating assembly, the harmonic balancer (not to be confused with the crank pulley) sits at the front of the crankshaft. Also known as the harmonic dampener, both names help describe its function, which is to absorb vibrations of the moving crankshaft, pistons, and connecting rods. This becomes more important at higher engine RPMs, as a poorly-designed or missing harmonic balancer can cause engine problems, in worst-case scenarios leading to worn bearings, loose bolts, stretched timing chains, or even broken internal parts.
A performance balancer stabilizes things, leading to a smoother-running engine, longer engine life, and steadier and more consistent ignition and valve timing. The harder you run your engine, the more important it is to use a good harmonic balancer as a stabilizing force.
With its location at the front of the crankshaft, installation does not require access to the engine's innards. While some nearby components may need to be moved for access, this is still a job that can be handled by most weekend mechanics.
The Professional Products brand of Powerforce+Plus balancers is worth checking out, as are the Super Damper balancers from ATI Performance.
Upgraded Motor Mounts
Is there a less-glamourous component on this list than motor mounts? After all, what do they do other than mount the engine to the chassis or unibody? On most modern vehicles, you can't even see them from the engine compartment. Most owners ignore them until one breaks.
But their function is important. They must secure an engine in place while its internals spin up to 8,000 RPM or more. That power needs to be smoothly transferred through the rest of the drivetrain and to the driving wheels. A steadily held engine does a better job putting that power to the ground, which is where you want it. Strong motor mounts help reduce unwanted engine motion, prevent wheel hop, and minimize vibration. At the same time, you don't want motor mounts made of metal, as that will transfer noise and harshness throughout the car, including into the passenger compartment.
Many of our performance motor mounts are made of polyurethane, which is a nice upgrade from rubber. The polyurethane adds firmness yet still allows some cushioning, an ideal compromise. All motor mounts wear out eventually anyway, so swapping out your old ones for a performance set is a great idea. Installation varies a lot from car to car, and on most vehicles is done from underneath. Be sure to put safety first by properly supporting the car off the ground. While you're under there, don't forget the transmission mounts.
Motor mounts from Energy Suspension are made from polyurethane, and are available for engines, transmissions, subframes, differentials, and many other undercar locations. Prothane offers polyurethane mounts for many popular domestic and import vehicles.
So there you have it! While we chose six of our faves, feel free to roam around at some of the other choices within Engine Performance, as well as selections from ignition, air intake, and fuel categories. There is bound to be a choice that meets your performance goals and still keeps you within budget.