Fuel line routing is everything...
Fuel line routing is everything to safety. This is the way Ford routed Mustang body fuel lines from '64 to early '67. From late '67 on, fuel lines were routed through the torque box for improved safety. You can use the late '67 body fuel line on your '65 through early '67 Mustang with or without the torque box.
We take our ignition and electrical systems for granted as if they happen by magic. A Mustang's electrical system follows the fundamental laws of physics and there are no exceptions. Fall short in your electrical and ignition system planning and you can count on winding up roadside.
The first area to address is proper grounding. We will even suggest taking grounding even further than Ford because it's that important. Because your engine and transmission sit on rubber mounts, they must be grounded to the firewall in order for both ignition and charging systems to work properly. If you've converted your classic Mustang to electronic fuel injection, it's even more important to be redundant in your grounding program.
One old law of physics is electricity. It will always find the path of least resistance, sometimes with befuddling results. A poorly grounded ignition system offers hit-and-miss operation. Sometimes your engine starts. Sometimes it won't. And sometimes it will just quit. Charging may be intermittent with erratic voltage regulator operation. It is suggested you have two forms of engine grounding-the factory cylinder head to firewall ground and another ground from block to chassis.
Rubber fuel line hose should...
Rubber fuel line hose should be high-pressure, fuel injection type which is also resistant to today's harsh fuel additives. Use stainless steel braided hose where you can and always avoid extensive lengths of rubber hose.
Range is a good thing to have...
Range is a good thing to have if you're going to road trip in your classic Mustang. It's easy to convert from the limitations of 16 gallons with the installation of a 22-gallon tank from a '70 Mustang. Remember, there are two types of 22-gallon tanks-one for California evaporative emissions and one for 49-state.
Another fuel system restriction,...
Another fuel system restriction, aside from fuel line sizing, is this fuel strainer in Holley 1850/4150/4160 carburetors. Remove it for best results. Just make sure you have good fuel filtration that is also 3/8 inch. Also, keep fuel inlet sizing in mind. If your entire fuel system is 3/8 inch, yet the fuel inlet is 5/16 inch, you have only 5/16 inch, which defeats the purpose of 3/8-inch fuel line. Make sure the carburetor inlet is at least 3/8 inch.
Don't forget distributor grounding, which is a small ground lead inside your distributor. Too many of us forget that little guy during tune-ups or PerTronix Ignitor retrofits. Because the breaker plate floats on nylon rub pads, you can't count on sufficient grounding any other way but the ground strap.
If you have good hood clearance,...
If you have good hood clearance, carburetor spacers are great torque enhancers. They increase air velocity thereby improving torque.
Ignition system selection depends on how you intend to drive your Mustang and the level of expected performance. Cruisers and weekend show cars are good to go with high-quality ignition points or a PerTronix Ignitor conversion, which eliminates old-fashioned ignition points. The Ignitor is the easiest upgrade you can make to a classic Mustang and it never requires maintenance. Install it, set the gap, and forget it.
If your Mustang project is more about high-performance driving, you may want to consider an MSD Ignition system or PerTronix's billet distributor, which is fitted with the new Ignitor III system for exceptional performance. Street Mustangs should get a distributor with vacuum advance, which helps the engine deliver both efficiency and low-end torque.
Marvin McAfee of MCE Engines...
Marvin McAfee of MCE Engines performs an Autolite distributor curving, dialing in the right amount of advance as it pertains to engine rpm. This is important to both centrifugal (mechanical) and vacuum advance systems.
Regardless of the distributor you use, always have it curved to expected driving conditions. In other words, have a qualified technician set up your distributor for your engine and how you intend to drive. MCE Engines does complete distributor rebuilds along with proper tuning for your application. There are also other professional distributor rebuilders and tuners out there such as Tim O'Connor, a Ford service technician, who has been rebuilding and tuning Ford ignition systems since 1966.
This is another area we tend to overlook. However, it is important to both performance and reliability. You want a low-restriction exhaust system, yet with enough restriction that will give you back pressure and scavenging. Velocity through header primary and secondary tubes along with low-restriction mufflers is key to the smooth flow of exhaust gasses and delivery of power. The choice of long- or short-tube headers depends on the amount of power your engine is going to make. As horsepower increases at high rpm, you're going to want long-tube headers. Shorty headers yield some improvement in exhaust scavenging because they do away with the restrictive roughcast surfaces and passages of stock exhaust manifolds. However, don't expect a huge gain in performance from shorty headers. Long-tube headers will give you better scavenging and velocity as rpm increase.
You may not believe this,...
You may not believe this, but ignition crossfire is a significant reason for poor performance because we tend to write it off as a simple misfire. Always route ignition wires in parallel, at least 1/4 inch apart whenever possible, to prevent crossfire.
It can be challenging to choose the right type of long-tube headers. You want custom-tuned headers with uniform length primary tubes and right-sized collectors for optimum performance at high rpm. Yet, equal-length header tubes can make things a bit crowded. It is all about compromise. One of the best long-tube header manufacturers we've worked with is Ford Powertrain Applications (FPA), which offers Ford buffs perfect-fit long-tube headers with ball and socket collectors that don't require collector gaskets. These headers tuck close beside your engine to take up minimal space.
Muffler choice and pipe size depends on how much power you intend to make. Pipe size should be proportional to power output. Pipes that are too large will lose precious torque. Pipes that are too small will cause excessive backpressure and heat.
Another important consideration is cabin noise levels. Although loud exhaust systems have been fashionable with hot rodders for generations, we're also a generation of deaf people from rock 'n' roll music and hotrods. You want good sound deadening and user-friendly mufflers for your road-going Mustang cruiser.
Good charging and starting...
Good charging and starting systems are what make the difference between getting there and not getting there. Unless you are married to original equipment, retrofit your classic Mustang with a 100-130-amp single wire alternator and a lightweight starter. Both are easy retrofits offering reliability without the hassle of old-fashioned electrics. Single-wire alternators eliminate your Mustang's external voltage regulator, which is often the biggest source of charging system woes. Original equipment Autolite/Motorcraft 45-65-amp alternators just aren't enough if you have a lot of accessories.
Flex-A-Lite introduced this...
Flex-A-Lite introduced this fan/radiator combo just in time to wrap up Project Reclaim from Mustangs Plus and The Restomod Shop. This is not for a stocker. However, when it's time to bump power above 350 hp or you're building a restomod, this is a great cooling package designed to simplify your efforts because all you have to do is install it.
Always go with a high-flow...
Always go with a high-flow water pump, like this one from Edelbrock, to optimize coolant flow.