Just ask Jay Leno.
When to Modify
When asked about whether it makes sense to modify a car, I tell people that it’s their car and they can do whatever they want. But I also suggest they consider that certain changes might reduce a car’s value, making it harder to sell and reducing event eligibility.
If a car is one of one or one of 40, I suggest keeping it stock. I might also think twice about changing its color. I have fewer qualms with production cars. In most cases, if you paint your car a correct color for your make and model, you’re all right. The same goes for interiors: Use the factory-correct material, pattern and color. Just know that you might get better money when you sell the car if it is in its original livery.
Many people add disc brakes, which is great if you want upgraded stopping ability. As with any change, be sure to save every original part and make any modification without cutting or welding.
As many collectors age, power steering is becoming a popular addition. Now there are small electrical assist units that can be tucked out of sight. We put these units in Ferrari Daytonas all the time and they only work below 20 mph, which is where you need the most help.
Air conditioning is another frequent addition, though a compressor is impossible to hide. It’s a great mod for a Mercedes-Benz Gullwing, which is virtually impossible to drive in summer months in some parts of the country because the windows don’t open fully.
What about electric fans? Again, it all depends on use. If you’re touring, installing an electric fan makes sense to protect your engine. Just be sure to mount it so it can be easily removed, because it will cost you at some judged events.
Engine swaps are more complex. Putting a 4½-liter engine in a 3-liter Bentley is no big deal in the eyes of the club, but when you put a Hemi in a 440 ’Cuda, it gets more complicated. Many other swaps also require cutting and welding and are hard to reverse, so they may hit you hard when it’s time to sell.
People make all kinds of other changes to their cars, like removing emissions equipment, swapping generators for alternators and changing wheels. But as long as you save all the original parts, make it your own and have fun with it.