You may recall the article entitled "The Slippery Truth About Oil" from the June '06 issue of HPP (also available at www.highperformancepontiac.com). In it, we discussed the negative effects some modern motor oils have on flat-tappet camshaft engines, and explained the organizations that categorize motor oil, the category designations, and the key anti-wear additives that were reduced, which are thought to be behind many of today's camshaft lobe and lifter failures.
At the time, we presented a few long-term solutions that included certain off-the-shelf products, among them commercial-grade oil, and General Motors' Engine Oil Supplement (E.O.S.). All seemed well until we learned that most 2007 diesel engines were gaining an exhaust system catalyst, which likely meant oil reformulation, and that GM discontinued its highly-concentrated E.O.S. product-two serious blows that struck panic into the hearts of hobbyists who relied so heavily on these products.
The fact remains that many hobbyists own vintage Pontiacs with flat-tappet camshaft engines, and the HPP staff is among them. Like you, we too were just as concerned about the matter and set out in search of solutions that wouldn't likely waiver with the next mandated reformulation. So we contacted several large corporations familiar to most hobbyists, and asked for comments on the current situation and any long-term solutions that could quell our concerns. Here's what they had to say.
In late June 2007, General Motors discontinued its Engine Oil Supplement without warning. E.O.S. contained a high concentration of desirable anti-wear additives, and was a popular hobbyist choice for flat-tappet camshaft protection. News of its discontinuance spread like wildfire, and many bought it in large quantities, depleting dealer inventories. There's been no word from GM of the product's return, but similar options are available from other suppliers and are claimed as suitable alternatives. | 
As we learned in "The Slippery Truth About Oil" in the June '06 issue of HPP, the American Petroleum Institute (API) sets the oil category standards, and its latest SM/GF-4 and CJ-4 certifications include lesser amounts of ZDDP, which many feel is a contributing factor to the high number of flat-tappet camshaft failures today. Additional information about the rating system can be found at www.api.org. | 
The API category rating of any certified lubricant can be found in the API "donut" that's typically located on the back label of any oil bottle. |
Amsoil
AMSOIL was the first company to market fully synthetic motor oils for all types of internal combustion engines. Its first gasoline engine offering was released in 1972, which spawned an entire industry. Today the company offers a wide range of synthetic lubricants, including those suitable for flat-tappet camshaft engines. We contacted AMSOIL's Director of Advertising, Ed Newman, and its team of technicians, for the company's perspective.
High Performance Pontiac: Can you discuss the recent oil reformulation that seems to have negatively impacted the automotive hobby?
Ed Newman: Beginning with all 2004 model year vehicles, auto manufacturers were required by federal law to warrant emissions system performance for 120,000 miles, and one system critical to emissions performance is the catalytic converter.
AMSOIL is a synthetic lubricant industry pioneer, and today the company offers a full line of motor oils that includes its (AMO) 10W-40, which is suitable for flat-tappet engines.
Part of the phosphorus was removed from motor oil because it had been linked to catalytic converter failure, and it's a key component in the high-pressure anti-wear additive, zinc dialkyl dithio phosphate (ZDDP). Since auto manufacturers must maintain catalytic converter system integrity for 120,000 miles, they began pushing oil companies to modify formulations, and those gasoline-engine oils that meet API SM, ILSAC GF-4, and API CJ-4 standards for commercial specifications to reduce ZDDP levels.
HPP: Can you explain how the reformulation directly affects flat-tappet camshafts?
EN: We've recently released an entire Technical Service Bulletin (No. MO-2007-08-08) discussing just that. Simply stated, engines with flat-tappet camshafts typically have an extremely high pressure-point between the lifter crown and the camshaft lobe, and ZDDP acts as a sacrificial chemical barrier that prevents the two from actually contacting one another. The concern is that the lower levels of zinc may not provide sufficient anti-wear protection in flat-tappet camshaft engines, and, in particular, those with high-tension valvesprings.
HPP: Does your company offer any products intended for use with flat-tappet camshafts?
EN: Extra protection is available with our Premium Protection chemistry, and consumers need to look carefully to find products formulated for flat-tappet camshaft engines. We offer a full line that contains this additive package and has a proven history. Products like our (AMO) 10W-40 and (ARO) 20W-50 gasoline-engine oils contain high ZDDP levels, and are perfectly suitable for flat-tappet cams.
HPP: Is there any chance your company could discontinue or reformulate these products in the future?
EN: As opposed to discontinuing these types of products, we're actually looking to expand the line as required, and are working with flat-tappet camshaft manufacturers to promote its value to this particular market. We're very committed to solving this problem, and are actively pursuing ways to specifically market these lubricants to classic car hobbyists.