We previously discussed mistakes that can be made in the restoration process, and now we discuss some of the many possible restoration mistakes on your car that can affect your final product. Classic car restoration projects can quickly become obsessions. Purchasing a vehicle that requires restoration is an excellent way of laying your hands on a classic car, and there are many tasks that can be carried out without the need for professional help. The most important thing to keep in mind when it comes to car restoration DIY projects is that very few things will really be as simple as you anticipate. When you are preparing for the restoration, a well thought out plan of attack is the best approach to avoid restoration mistakes on your car.
To help you avoid restoration mistakes on your car the following are some examples of areas the DIY mechanic can get in trouble with a classic car restoration.
Sheet-metal Replacement Woes
Not many of us tackle sheet-metal replacement. Some of us do with catastrophic results. Quarter-panel replacement mandates extraordinary attention to detail and doing the job with doors and decklid installed. You need those points of reference to get quarter-panel fitment spot on.
Electrical Circuit Protection
We are convinced electrical fires probably do in more muscle cars than accidents or natural disasters. Your muscle car’s electrical system—especially if you are going back with the original half-century-old wiring harness—mandates methodical installation and security. It needs a fresh wrap of electrical tape to prevent any chafing, and it should be secured properly. Watch out for any critical areas where wiring may ground against a hot exhaust manifold, header, or sharp sheet-metal edges.
Make sure you have adequate circuit protection going in. Not all classic cars have circuit protection. This can mean a master fuse or fusible link between the battery and main feed. Or it can mean disconnecting the battery whenever the car is parked in your garage.
If you are building a driver-quality vintage car, opt for one of the better aftermarket electrical systems will offer you more options and circuits. There are also OE-style wiring systems and parts from a variety of sources that will renew your classic car’s old electrical system.
Is It Grounded?
Most electrical system woes are caused by improper grounding. Restorers forget to ground the engine to the chassis. Smaller, seemingly insignificant grounds (most are black) get left disconnected, and accessories fail to work. Headlights are brown instead of white. Accessory operation becomes intermittent. Engines do not start. Or they start and quit. If you are having these problems, check all grounds.
Using Old Brake Plumbing
We are astonished at the restorations we have seen through the years where restorers cleaned up and reused 50-year-old brake lines and hoses. Restorers want the authenticity of original plumbing and hoses, but safety should not be compromised for authenticity. Always opt for new lines and hoses. And be careful with new old stock when you find it. The elements are hard on reinforced rubber hoses even when they have been sitting on the shelf for 50 years. There are sources that provide OE tubing and hoses as well as flexible braided stainless brake hoses and both galvanized and stainless tubing for a wide variety of car applications.
Over-carburetion
Ever since the dawn of the internal combustion engine, common logic has always been bigger is better. If 389 cubic inches were good, then surely 400 or 455 must be even better. The same can be said for carburetors. If 600 cfm places enough pressure at your backside at wide-open throttle, 650 or 700 cfm must be even better. However, this has not always been true and still is not all these years later.
Carburetor size should be proportional to displacement, cylinder head type, compression, and cam profile. You can wind up with too much carburetor and lose both horsepower and torque. Ideally, you will size carburetion to where it is optimum for engine size and component selection.
Exhaust Pipe Sizing
Here is another one that trips enthusiasts up repeatedly. Like carburetion, it is often believed bigger pipes are better. However, when exhaust pipe sizing becomes too large, low to mid-range torque suffers. Even if you are running a big-block, pipe sizing does not need to be any larger than 2-1/2 inches. When you start courting the 3-inch mark, you start losing precious torque, which is what gives you the traffic-light-to-traffic-light advantage. You may also wind up with pipe clearance headaches. All the horsepower in the world is meaningless in a street muscle car when your ride is a slug at low rpm. Sewer pipes are for public utilities, not muscle cars.
Noise Levels and Hearing Loss
While we are talking about exhaust systems, let us address something else: noise. Back in the day, when most of us were young and hot rodding in a loud and obnoxious way was very cool, loud exhaust systems were very much in style. Few things are more discouraging than an investment in a throaty bark, only to discover the resonance out there on the open road takes a toll on your hearing (not to mention conversation).
While few things are as adrenaline-inducing as the throaty roar of an all-American V-8, many of us have discovered the penalty of a loud exhaust system is hearing loss. You may opt for a soft throat at the tailpipes, which is available from a number of respected exhaust system manufacturers. Sound deadening packages are also available to weave quiet into your classic muscle car. Whatever you choose, take good care of your hearing. Once it is gone, it has gone forever.
Make Mine 1,000 Horsepower!
We are always asked how to build insane levels of power into classic cars. Question is, how much do you need? All 700 to 1,000 hp nets you is bragging rights at the local cruising spots. But it makes little sense for street power. Power in the hands of those who know how to handle it is great. Power in the hands of the inexperienced can get you (and others) killed. What is more, you better have a chassis, brake system, and tires that are up to the task. Are you really ready for 1,000 hp?
Outrageous Hose Routing
We must wonder what people are smoking when we examine some muscle car restorations. Cooling system hoses routed all over the place. Radiator hoses up against accessory drive brackets. Heater and bypass hoses chafing against intake manifolds, carburetors, and distributors. The result of this practice is a burst hose and coolant all over the freeway. Radiator hoses should never touch anything. Heater hoses and transmission cooler lines should be properly routed and not touching anything through which they can chafe.
Carpet Trimming
What is it about carpet installation that makes a calm person insane? Molded carpet never comes out of the box ready to install. It always requires trimming, and rarely does it just fit into floor-pan pockets. We get into trouble when we trim too much and wind up with gaps between sill plates and carpeting. Trim carpet in baby steps. Better to have excess than not enough and the expense of carpet replacement.
Cold Fact
If ever you have wrestled with upholstery, you understand this one. Cold vinyl does not stretch very well, yet it tears quite well. Before you begin the reupholstery process, always lay vinyl out in the hot sun or in a very warm environment, which will give it flexibility and make it easier to work with. Fighting the fight with cold vinyl gets frustrating and expensive.
To Lube or Not to Lube
The haunting question with door checks and window mechanisms is when to lube, what type, and how much? We are often guilty of slapping tons of grease on door checks, window regulators, and latch mechanisms, only to wind up with it in places it is not wanted. Door checks, window regulators, and latches should be lubricated with white lithium grease and in modest amounts. Same rule that applies here also applies to gasket sealer: just enough to get the job done.
Wrong Brake Pads
This is an easy mistake to make. Street cars should get organic or semi-metallic brake pads, which are highly effective. Metal and ceramic pads are for the racetrack not street use. High-heat racing pads will eat up your rotors and drums. What is more, they are noisy.
Improper Clutch Selection
Are you still running around with a vintage three-finger Long-style clutch? Although you can still buy new three-finger clutches, they are not the best choice because they yield a ton of pedal pressure and knee replacement surgery. What you want today is the diaphragm-style clutch, which provides plenty of power-transmitted grip and light pedal pressure. Modern Driveline offers a complete line of Superior diaphragm-style clutches and flywheels for all types of classic cars. There is no reason you should ever tolerate a stiff clutch pedal.
Sticky Stripes!
When you install stripes or other kinds of graphics on a vintage car, always use soapy water for the positioning process. Otherwise, once you lay down graphics, you are stuck with the result because they cannot be removed or repositioned. And one other thing: Make sure the surfaces are hospital clean.
Strange Badge Placement
Whenever we see this, it is like fingers on a chalkboard: ridiculous, tasteless badge and emblem placement. It is either improper factory emblem placement or add-on badges that do not have any place on a classic car. Do not give in to the temptation.
When a Safety Is not Safe
We must wonder how many scars, torn human tissue, and heated expletives have resulted from improperly installed cotter pins. Whenever you install cotter pins, always trim, and bend them over to where they cannot injure anyone during chassis service.
Thermostat Removal
This is an old saw but still applies today. It has long been perceived that removing the thermostat will solve overheating problems. However, this has never been true. Your engine’s thermostat is the traffic police officer for coolant flow from engine to radiator and back again. The thermostat keeps coolant in the engine for heat transfer to the coolant. When it reaches the specified 160-, 180-, or 192/195-degrees F (depending on manufacturer recommendation), it opens, releasing hot coolant to the radiator for heat transfer to the atmosphere. Coolant from the radiator flows into the engine, and this heat conductivity process begins all over again.
When you remove the thermostat, coolant never has a chance to absorb engine heat, nor does it have a chance to give up heat to the atmosphere. On the open road you might be able to get away with it. In traffic, you will overheat and boil over.
Do not Collapse Hoses
And one more cooling system related tip. Some applications call for the use of an anti-collapse spring in the lower radiator hose to prevent hose collapse during high-rpm operation. It is better to use an anti-collapse spring than not to use one in the interest of engine health. If your vintage car overheats on the open road at speed, you need the anti-collapse spring, which should be made of stainless.
Finally
Most people never get to the finish line in restoring a classic car, but you do not have to be one of those people if you follow our blog and be patient, and thorough in following the plan you set at the beginning of the process. You will find plenty of support to help so do not let your ego get in the way for a rewarding experience. As we have mentioned there are plenty of opportunities to make mistakes, but the key is to keep them small and manageable so avoid restoration mistakes on your car that will take you off your plan to completion.
