Dodging Bullets in Your Vintage Mustang

Written by Don Stewart | 28 February 2009

If the greens and their crusher-proposals don’t give you hives and make you wonder how difficult it will be to pursue the vintage Mustang hobby in the future, then how about the threat of retitling vintage ponies as replicas when they’re purchased out of state. If those two things don’t bother you, checkout cylinder heads with VSR and motor oils with low ZDDP? It’s like dodging bullets from a Hopalong Cassidy 6-shooter where the thing keeps firing lead projectiles even though Hopalong never takes time to reload. Substitute government for the Hopalong visual and sometimes it seems like legislative carpet bombing.

Don’t get me wrong. Excluding crusher mania, the government controls aren’t necessarily bad or wrong for this day and age but vintage Mustangs come from a different age. The new regulations and the old Mustangs don’t always mesh.

The Crusher

Back in 2002, SAN (SEMA Action Network), with substantial aid from enthusiasts, was able to defeat proposed Federal scrappage legislation. Congress had a bill under consideration whereby owners of old cars would be urged to cash them in for $700 each, the idea being that worn out, high carbon footprint, clunkers should be removed from the road through a government purchase program. The obvious destination for the cars was the crusher.

The logic behind the proposal, according to its sponsors, was to entice the owners of such cars to take the $700 payment and apply it toward the purchase of newer, safer, cleaner cars. SEMA and hobbyists rebelled because if the bill became law, one probable result would have been the destruction of many vintage cars and most parts cars used in the hobby. Another result would likely have been a substantial reduction in the need for aftermarket parts from SEMA-member companies.

With typical myopic focus, some of our federal legislators thought it was time to revive the initiative and “hide” it in today’s economic stimulus program. Again strong opposition from SAN lobbyists and a letter campaign by hobbyists successfully resulted in reconsideration. But like a bad penny, the initiative won’t go away.

The latest thrust, according to SEMA, comes in the form of proposed bills H.R. 250 sponsored by Representative Henry Waxman and S. 247 sponsored by Senator Diane Feinstein. It’s the so called “Accelerated Retirement of Inefficient Vehicles Act” whereby participants would receive cash vouchers ranging between $2,500 and $4,500 for vehicles surrendered to the program. They would be required to purchase a replacement vehicle from an EPA CAFE class rated at least 25% more efficient than the class represented by the surrendered vehicle. The proposed volume bogey is one million vehicles scrapped per year for four years.

SEMA is fighting the bills and has requested assistance from hobbyists. Read more details at www.semasan.com, the online SAN site. The site includes contact information and suggestions for the wording to be used in letters of opposition.

Retitling

Because of DMV misclassification, favoritism, failure to follow procedure, and failure to detect fraudulent out of state titles, North Carolina vintage car enthusiasts can count on an extra step when trying to title a car purchased from another state. In one way it’s a good thing but in another, it can be a major headache and, possibly, a costly one.

In 2004, a friend of then Division of Motor Vehicles Commissioner, George Tatum, used his friendship to leverage a 1937 Ford truck replica into a truck misclassified as a real vintage truck. When this came to light, a review of vehicle titles was ordered by Mr. Tatum and then he resigned.

Overall, more than 100,000 titles were reviewed and inspectors looked at more than 600 vehicles with a focus on those that were custom built plus those 35 years old or older. In addition to several more misclassified replicas, roughly 900 so called original vintage vehicles brought in from out of state were found to have fraudulent titles. Details are hard to find but if my interpretation is correct, the 900 vehicles were mistitled by an Alabama company and then retitled as true vintage cars in North Carolina without verification by the DMV.

Exactly what happened in Alabama isn’t clear. Perhaps it was a case of using the VIN plates from totaled cars or plates from scrapped cars to build cars misrepresented as original and titled as such. Whatever it was, North Carolina DMV inspectors now have to certify the originality of an out of state vintage car before a title can be issued. That leaves the door wide open for a subjective opinion; i.e., what exactly does original mean?

If original means unmolested and just as the factory built it, that doesn’t leave many out of state Mustangs to choose from. If it means a car that’s been well cared for including replacement of worn parts and/or damaged and rusted panels, that’s a different story. I wasn’t able to find a clear cut definition.

A car that’s deemed to be original can be titled as an original using the original factory VIN. On the other hand, one that doesn’t satisfy the inspector, will apparently be classified as a replica and a new VIN will be assigned. A title will be issued using the new VIN and the car will be shown as a current year model.

How would you feel if you bought a pristine MCA gold winner from out of state and then couldn’t title it as a vintage car in North Carolina? Apparently, that could happen if the inspector doesn’t approve the car’s originality. For example, one article I read hypothesized that something like replacement front fenders lacking a proper stamping plant date code could indicate to the inspector that the car wasn’t original. Suddenly, your new pride and joy would lose its status and its value as a vintage car.

So be aware of the risk, if you’re looking at out of state vintage cars. Touch base with the DMV to verify that you will be able to title it as a vintage car before you make the purchase. Obviously, no one wants to get ripped off by an unscrupulous seller so capturing fraudulent vehicles is a safeguard that we can all appreciate. But on the other hand, no one in the hobby wants an honest car to be reclassified as a replica just because it’s a restoration.

If you’re looking for a bottom line, here it is. The highway use tax on a vintage car is much lower than it is on a current year model. Which way do you think the inspector will lean if there are any questions? Ah, the state DMV. Gotta love ‘em.

VSR

Tetraethyl lead was first added to gasoline in 1923 because it boosted octane and made pre-ignition-knocking less likely. That was the good news but the bad news was the toxicity of lead.

As EPA emissions mandates became part of our lives, we learned that cars with catalytic converters couldn’t use leaded gas because it poisoned the converter. But catalytic converters weren’t required until 1975 so a broad based monetary incentive to begin refining and selling unleaded gas didn’t occur until then, lead toxicity notwithstanding. Yes, unleaded AMOCO clear was successfully marketed for several years prior to 1975 on the basis of lower combustion chamber deposits but other brands continued to sell leaded fuel.

As time passed, there were fewer and fewer pre-’75 cars on the road and the need for leaded gas declined annually until it was totally phased out by EPA directive effective January 1, 1996. With nearly the entire fleet having catalytic converters by 1996, it made sense to eliminate leaded fuel from gas station menus while, at the same time, resolving the last remnant of the toxicity issue. Unfortunately, all remaining pre-’75 cars, including our vintage Mustangs, were left in the lurch because their engines weren’t designed to burn unleaded fuel. Early engine designs took advantage of the higher octane rating and another desirable property of lead—its ability to lubricate at high temperatures.

Exhaust valves operate at arguably the highest sustained temperature of any part in an engine’s combustion chamber. Without the use of special metallurgy or the availability of a protective interface, exhaust valve faces microweld themselves to the valve seats when they close. Welding is the result of temperature and the mechanical load from the valve springs. When the valve opens the next time, it drags out metal from the seat causing microscopic damage. This damage repeats every time the valve closes and opens. It becomes more severe at higher engine speeds and/or at heavier loads, when the valves run even hotter.

Special materials weren’t used in the pre-’75 engines but tetraethyl lead provided a protective interface. Lead and its compounds aren’t volatile at combustion chamber temperature so each exhaust stroke offered the opportunity to deposit lead residue on the valve seat. The residue provided a so-called “soft landing” for the valve when it closed, preventing microwelding and subsequent damage.

There are mixed opinions about how long it takes for microwelding to cause enough valve seat damage to affect engine performance. But one thing is clear. Burning unleaded gasoline in earlier engines promotes the damage. It progresses with time, engine speed, and load and it causes the exhaust valve to slowly recede into the cylinder head, affecting performance at some point. The phenomenon of sinking valve seats is referred to as valve seat recession or VSR.

What’s the remedy? Take the head(s) off the engine and do a valve job. As part of the repair, have chrome-nickel alloy hardened valve seats installed for the exhaust valves. Replace the exhaust valves themselves with Stellite-faced stainless steel valves to complete the upgrade. Or if recession hasn’t damaged the head excessively, you might try substituting the new valves without installing hardened seats. Talk it over with your machine shop.

Also talk over with your machine shop the probable need to replace worn valve guides because lead residue was the only source of lubrication for the exhaust valve stems. With unleaded gas, the source of lubrication was shut off in that area too.

ZDDP

As more is learned about controlling emissions, many things change. VSR related to unleaded gasoline was just discussed. Another change has to do with additive packages in engine oil. This one is serious enough to bring the engine in your vintage car to its knees relatively quickly.

The newest API motor oil designation is SM and it complies with the latest International Lubricant Standardization and Approval Committee (ILSAC) GF-4 designation. It’s the most readily available oil on the shelf at your favorite auto supply store. But unfortunately, it’s not backward compatible with flat-tappet camshafts used in older engines. Unless you’ve upgraded to a roller cam and roller rockers, using API SM in your early Mustang engine will cause significant premature cam lobe wear and rocker pivot wear. If someone tells you otherwise, don’t believe them.

The wear occurs because in API-SM oils, the antiwear additive called Zinc Dialkyl Dithio Phosphate, ZDDP for short, has been reduced below the minimum level needed for flat tappet applications. The reduction was made to avoid unproven but suspected phosphorous poisoning of new-generation, long mileage, catalytic converters. GF-4 oils have no more than 800 parts per million (ppm) ZDDP whereas the absolute minimum level required by flat-tappet cams is 1000 ppm, 1200 to 1300 ppm is much better.

What is it about ZDDP that protects the cam lobes? Why doesn’t the oil do the job on its own? To start with, it’s important to realize that cam lobes aren’t oiled under pressure; they depend on splash. If you imagine the high pressure sliding action of the cam lobe against the bottom of a flat tappet, you can visualize the oil being squeezed out of the contact area. That’s exactly what happens with resulting metal to metal contact and the need for another form of lubrication. The phosphorous in ZDDP acts as that lubricant.

API-SL (ILSAC GF-3) was the oil generation prior to API-SM. It’s the most recent formulation with enough ZDDP for flat tappets, but just barely at 1000 ppm. Going back another generation, API SJ (ILSAC GF-2) was better with 1100 ppm. Earlier API designations (API SA through SH) had plenty of ZDDP but they’re all obsolete and generally unavailable except at some online sources. And there isn’t much SJ or SL on the shelves anymore either but, again, there’s online availability. Some of the current Mobil 1 oils meet the requirement as do some of the oils from Redline, Amsoil, Shell, Valvoline, Pennzoil, and others. Do your homework and buy your oil carefully. You don’t want to wipe the lobes off your cam or damage the bottom side of your flat tappets. The badly worn cam pictured with this article shows what will happen if you use oil with insufficient ZDDP.

A new ILSAC specification should be available by summer 2009. It will carry designation GF-5 and reportedly, it will reinstate the backwards compatibility seen in oils prior to the GF-4 generation. If you decide to try it, research it carefully before you buy it. Make sure you’re convinced that it will properly lubricate your flat tappet cam because there is no indication that ZDDP will be increased. That means some other additive will be required in place of ZDDP.