Text by Dmitriy Orlov
Petrolheads have various reasons for wanting to modify a vehicle, be it an expression, obsession, perfection, or a need for speed. Regardless of the reason, however, you should have a specific goal in mind.
If you are restoring a classic, pushing a street car to the limit on the track, or anything in-between, you should always decide what you want to accomplish. This applies whether you take your vehicle to a specialist or do it yourself. In the world of performance aftermarket, a logical approach can save both money and time and make the vehicle experience more fulfilling. We call this plan a build path, and defining your goal or objective is the first step in determining that path.
On any level, a major concern is your budget. Enthusiasts often want more power or to increase handling without really understanding what it is involved, even on a basic level. Cost climbs exponentially with every 10–30 hp gain, and realizing this may help you from being shocked when you get the estimate for the work.
The steps involved in modifying and building a vehicle can span a wide range of work and scope. You could take the daily driver and turn it into a weekend warrior at the local track, or you could start with a car that might not even have an engine (known as a shell) with the intent of building a full-blown track car or even doing a complete restoration. By understanding the three primary types of goals, we can begin to decide what exactly we want to achieve.
Perhaps the most common and most likely the cheapest goal is making the daily driver more fun to drive on the street. You want more feel for the road, a little more pep from the engine, and maybe some more aggressive styling. Small things can go a long way and be affordable, while keeping the car drivable and tolerable for long periods of time.
Show cars are works of art and require considerable time, attention to detail, and quality workmanship. Costs can be astronomical due to materials used, equipment, and the amount of time and effort that is needed.
Drag racing, road racing, and rally or other types of automotive racing demand different environments and conditions. Drivers need to be able to push the limits of their cars, which may need extensive modifications to handle performance goals as well as meet certain safety requirements set by racing leagues. The cost of meeting these standards can climb quickly (simple bolt in harness bar vs. full cage).
No matter your end goal, having a car that runs properly is the right place to start. To modify the vehicle, maximizing its potential and pushing its engineered limit, you want to make sure that your car performs very well. Regular maintenance and preventative maintenance are always necessary, but additional maintenance may be required, as modifications cause additional stress across the board.
Checking oil chemistry and metals and the wear of engine components can reveal clues about engine health. Tip: a quick and dirty way to check engine health is to look at the underside of your oil cap. If it has a ton of debris and isn't clean (obviously aside from oil), then you can usually assume the engine is in similar condition. A leak-down and compression test can also indicate any problems.
Checking and maybe even selecting higher-grade fluids will be beneficial.
Replacing and keeping track of seals, gaskets, and hoses is critical.
Wiring and sensors should be in check, and electronics should be trouble free.
Such things as filters, spark plugs, and injectors may need upgrading, depending on modifications, but should be maintained as well.
If the vehicle passes the basics of normal operation and is healthy enough to be modified, move on to learn about modifications that HELP the car take on more stress. Many generic and vehicle-specific options can ensure longevity and lessen potential failure.
Plug wires and spark plugs may need to be upgraded to provide more consistent and reliable charge. Larger fuel lines, regulators, and filters serve a similar purpose in supplying sufficient fuel. Catch cans, PVC system modifications, new seals, and gaskets will help clean up the engine and keep it clean in the future. New bushings in the suspension system or subframes can withstand greater force and will flex less. A great many other things also need to be considered, and everything depends on platform, modifications, and inherent vehicle "flaws” or the limits for which it was originally designed. Keep in mind that some cars are overengineered, but many are made for the exact output and performance specs listed on the sticker. Adding anything more might mean a lot of supplementary additions.
Meeting your goals
Understanding the vehicle, the goals, and the scope of the work can allow you to scale and gauge how you want to approach the project. Consider your budget and the time and resources necessary to reach your goal. Furthermore, research the capabilities and limits of the car so that you aren't reaching for the stars in trying to do something that is almost physically impossible and not cost effective. Learn about the companies and vendors that provide parts and services for your platform, and stay in touch with the community and experts who might know more or have even gone through the same process.