Let’s talk engine build for a minute. I like to browse the forums and groups on facebook and one thing I see that seems pretty much universal across all platforms is people wanting a “fully built” block so they can make 500+ WHP. Well recently it seems to be people wanting 600+ WHP, and that’s just awesome. Who would not want a car capable of crushing some of the highest end supercars for a fraction of the price? So let’s talk about what we will need, and I’m going to use Subaru as my platform for this blog.
The most basic type of engine build that would be great for someone looking for more reliability and don’t want crazy power numbers would be upgraded pistons. The factory WRX and STI pistons leave much to be desired for high power. They are great for low noise, low oil consumption (no jokes please haha), and long life at low/stock power levels. They have a notorious weak point which is the ringlands, which is the portion of the piston which support the rings.
A good aftermarket forged piston will not have the same problems as the stock piston, so you will be able to run more power, more boost, and higher pressures without the fear of the ringlands breaking apart on you. Now you might ask, why not just throw in a set of pistons and call it a day? Well a forged piston will need to be physically smaller than the stock piston as it will expand more once warmed up, so on a cold start you will see more engine noise, oil consumption and you will want to make sure the car is warmed up fully before flogging it around. Finding a piston which fits your power goals and driving style will be a very important step, but there is a piston out there for you regardless of your goals and needs.
Looking for even more power? Great! This is where you get deeper into the engine and start looking at connecting rods and bearings. The connecting rod is the critical component linking your piston to the crankshaft so going with a high quality rod is paramount to a successful build. There are many rods out there, which range from mild to wild and the price will generally reflect that, but for most people a quality H-beam rod will be more than enough for most high power builds. Ensuring the crank and rods can withstand the high stress that comes from high power, you want to make sure to install a set of quality bearings. Upgraded bearings will be able to handle more heat, stress and will have better lubrication properties to ensure your engine stays in one piece.
To keep everything together and sealed you may want to invest in a set of head studs and a quality head gasket. The head studs are what keep your head bolted to the block and a quality aftermarket set will be stronger than your stock bolts and will resist stretching under the higher pressures you will see with more power. The Headgasket is what will seal the enormous amount of pressure that you will see between the block and the heads. Making sure to get a proper seal requires a quality gasket along with a bit of machine work to ensure the mating surface of the heads and the block are straight and free of imperfections.
With the above listed parts you now have a “built” block that can withstand much more abuse, power and boost compared to your stock setup. If done right and all the tolerances are in spec, this block should give your years of trouble free performance.
Now what if you’re looking to go even further? This is where we get into head work. Now the most common thing would be to install a set of cams, maybe some valve springs and retainers, but you can get crazy with the headwork if you prefer to extract every bit of power as you can out of your engine. Everything from porting, oversized valves, angled valve jobs, lightweight valve train using exotic materials and ultra-high flowing cams.
Everything depends on what your goals are and what you need out of your engine. It’s always best to discuss the build and your requirements beforehand to make sure you are getting the correct parts. If you’re going to build it, build it right the first time!