There are plenty of reasons to swap a late-model engine with EFI into your classic car. But, there are also a lot of things that make it difficult – like fuel delivery. We talked to Johnny McDevitt, director of vendor relations at Pace Performance, and got expert input on performing a late-model engine swap.

When it comes to upgrading an older fuel system for a swap, you can convert the existing tank to operate with the new equipment, bolt in an EFI-ready tank, or you can use an inline fuel pump that can work with either a fuel cell or a factory tank that has a sump installed. Each option has its own merits and a reasons why it might be a better option for you.

“Modifying your stock fuel tank to accept a drop in EFI pump-module is easy, because it can work with any tank and is relatively inexpensive.” McDevitt explained. “The drawback to modifying an original tank is that the tank may be dirty or rusty inside, and you need to take care when working with a used fuel tank.

The advantage of buying a new EFI-ready tank according to McDevitt is, “They come complete and ready to install with a pump and sending unit. They are typically more expensive, and a bolt in tank is not available for every application.”

Option three is to use either a fuel cell or a stock tank with an add-on sump, and an inline fuel pump  and regulator. Using a fuel cell makes for an easy plumbing job, and may be less expensive than buying and modifying a stock tank. The downside of a fuel cell is that they take up space in the trunk, where a direct-fit tank or modified stock tank will not.

Adding a sump to a stock tank involves cutting and welding of the gas tank, and can be extremely dangerous if you aren’t careful. This is still a viable option because it is also inexpensive and lets you use the stock fuel tank. A major drawback is this option is not an easy do-it-yourself task for some people.

When upgrading, “Don’t let price dictate your decisions,” McDevitt told us. “The cheapest option is not necessarily the best option for your application. It is also important to match your fuel system with your horsepower output.” McDevitt also recommends that you incorporate room to grow. “If you are considering increasing your power output in the future, plan ahead and make sure the system you are putting together now, will accommodate your future plans.”

Take note of the quality plumbing and fittings used with this in line fuel pump.

McDevitt concluded with, “Modern engines will require an electric fuel pump as opposed to an old-style mechanical fuel pump.” Even if your vehicle had an early-style throttle body fuel injection system, it likely only carried a PSI rating of around 40 pounds. A modern engine uses up to 58 psi. It’s also important to upgrade your hoses and hose ends to handle the higher pressure requirements. “Parts store hose clamps and rubber line aren’t up to the task of keeping your fuel line in place, and your vehicle safe,” McDevitt explained. “An electric fuel pump will continue pumping fuel even if a .25-cent hose clamp fails.” Avoid line blowouts, upgrade your hoses and clamps. It’s worth it.

Any of these options is a great way to improve your fuel system. Whichever route you go, make sure that you weigh your options and consider all the advice provided by McDevitt. If you are working on this kind of conversion – or are considering one –  and you aren’t sure about something, just give the experts a call. They are there to help.