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SCCA Mazda Engine Builder Trusts Only AMSOIL

Championship Engine Builder Trusts Only AMSOIL

More than 1,080 miles covering six states separate Jesse Prather Motorsports, in Topeka, Kansas, from Virginia International Raceway.

And yet Jesse Prather’s influence at the track in October for the Sports Car Club of America’s (SCCA) annual “Runoffs” was unmistakable as an estimated 20 cars had one of his motors under its hood. In 2017, that number was 32. And two of those cars won national championships that year.

Top driver becomes top engine builder

That’s all to say that Jesse Prather is a big name in SCCA road-racing circles, particularly for competitors at the Runoffs, the SCCA’s biggest event. Many of them source their engines from Prather’s shop, where he puts his wealth of racing experience to work.

Although Prather has raced himself, winning three SCCA national championships, and has built race cars, today he mostly builds high-performance engines. He’s developed a niche building Mazda engines, but he also builds Honda, BMW and other foreign-made engines.

No doubt his father’s experience racing British sports cars for parts of three decades played a part in Prather’s career. Prather’s father opened a racing shop in Kansas around 1990, where Jesse worked for 10 years. It was there he started working on Mazdas.

“A customer wanted me to build a rotary engine for his RX-7, and it just kind of snowballed from there,” Prather said. His success behind the wheel laid the foundation for his success as an engine builder.

“[When you win], people want to know where you’re getting your equipment from. I built it all myself, so that’s how I started this business.”

AMSOIL Break-In Oil key to success

Today, Prather runs his own business, and AMSOIL products are a huge part. In fact, every engine that leaves Jesse Prather Motorsports is shipped with AMSOIL Break-In Oil inside the crate. It was this product that drew Prather to AMSOIL several years ago.

“I was looking for an oil that would seat rings properly, but that I could also run hard on the dyno,” said Prather. “With a lot of the break-in oils out there at that time, you couldn’t run the engine hard on the dyno because it couldn’t take the heat that we put them through on initial break-in.”

Break-In Oil (SAE 30)

Engine break-in is vital to building a championship racing engine. If the piston rings don’t seat properly against the cylinder wall, engine compression can suffer, reducing horsepower.

In Prather’s case, engine design posed additional challenges.

“We used forged pistons with thin rings to reduce drag in the bottom end of the engine,” he said. “I used to always have a lot of trouble getting these rings to break-in to the cylinder wall.”

Prather tried several techniques to solve the problem, but AMSOIL Break-In Oil proved most successful. “Now the rings seat in the first 10-15 minutes versus having to run an engine 2-3 hours before the rings seat – and sometimes they’d never seat,” he said.

“Every single engine I ship has AMSOIL Break-In Oil shipped in the crate with the engine. It’s a required step to using a Jesse Prather Motorsports racing engine.”

Jesse Prather

Racing oil just as important

Prather’s use of AMSOIL products doesn’t end after break-in.

He recommends AMSOIL DOMINATOR® Synthetic Racing Oil in his engines due to its excellent wear protection and heat resistance.

(Should you use racing oil in your daily driver? Find out here.)

“Even after running fairly high oil temperatures during a race, the oil does a good job absorbing the contaminants we put it through,” said Prather.

Most customers have their engines rebuilt after two years or 20 hours. It’s then that he sees DOMINATOR’s excellent performance first-hand.

“When I get these motors back, I see that the bearings have been protected. We don’t have bearing scuffing. We don’t have bearing deterioration. I don’t see extensive wear in some of the chain-driven camshafts. I don’t see excessive wear on the bore or on the pistons.”

“It’s amazing; it just works. And we abuse it. This oil gets abused day in and day out.”

Jesse Prather

DOMINATOR® 10W-30 Racing Oil

Prather’s use of AMSOIL extends beyond the motor.

He uses Synthetic Manual Transmission and Transaxle Gear Lube in all synchronizer-equipped transmissions. He also uses SEVERE GEAR® Synthetic Gear Lube in the differentials and some transmissions not equipped with synchros.

As Prather says, wear protection is the key to a good differential fluid, particularly in high-demand racing applications that undergo tremendous pressure. And SEVERE GEAR meets his demands.

“Even up to 300°F (149°C), SEVERE GEAR doesn’t break down; it continues to protect. It can take the heat and it still protects those gears.”

Jesse Prather

New Easy Pack for simple differential oil servicing.

AMSOIL isn’t just for racing

Prather makes sure his customers know just how well AMSOIL performs.

“I tell them it does the best job protecting their engine, period. I’ve been around racing for 40 years, and I tell them it works the best for what we’re doing with these cars.”

“I’ve seen the least amount of wear in the engines and the best protection of any other oil I’ve ever used, and I’ve used a lot over the years.”

Jesse Prather

While Prather has notched plenty of wins on the track, he derives more satisfaction from seeing his customers win.

“I’ve had a customer win a national championship every year for the last multiple years,” he said. “And that really is what drives me to keep pushing.”

As with many AMSOIL users, Prather’s initial positive experience with one AMSOIL product convinced him to try others. He now uses AMSOIL products in everything he owns with an engine.

“I’ve expanded into using AMSOIL in all my engines, from my lawnmowers, to my RV, to my skidsteer, to all my family’s vehicles. I use it exclusively. I don’t have any other oils in my shop,” he said.

And the reason he uses it, as his customers have found out, is that it simply works.

“That’s all that matters to an engine builder. It’s not about being loyal to a certain company – it’s about what works. I trust AMSOIL exclusively with all my racing engines,” said Prather.

Why You Should Be Wary About Using Break In Oil in Powersports Equipment

Why You Should Be Wary About Using Break In Oil in Powersports Equipment

Marco Navarro asks on our Facebook page about break in oil, with attention paid to powersports engines.  (Break in oil importance, drain interval on it, and applications. To include motorcycles and ATVs since life of engine is shorter and rebuilding occurs more often.)
Thanks for the question, Marco.

Let’s get to it.

Maintaining an engine is a constant fight against wear. Over time, wear not only results in expensive damage, it reduces compression, robbing your engine of power.

That’s why it can be tough to accept that “controlled wear” during a new or rebuilt engine’s break in period is critical to maximizing its power and longevity.

Take a seat

One of the primary reasons to break in an engine is to seat the piston rings, and that means allowing the rings and piston skirt to carefully wear down the peaks (called asperities) on the cylinder wall.

The images show what we mean.

Although a new or freshly honed cylinder appears smooth to the naked eye, it contains microscopic peaks and valleys. If the valleys are too deep, they collect excess oil, which burns during combustion and leads to oil consumption.

The sharp peaks, meanwhile, provide insufficient area to allow the rings to seat tightly. That means highly pressurized combustion gases can blow past the rings and into the crankcase, contaminating the oil and taking potential horsepower with it.

Breaking in the engine wears the cylinder-wall asperities, providing increased surface area for the rings to seat tightly. The result is maximum compression (i.e. power) and minimum oil consumption.

Getting the shaft

That brings us to the other primary reason to break-in an engine: to season, or harden, the flat-tappet cam. Flat-tappet cams can wear out faster than their roller-cam cousins, especially in engines modified with high-tension valve springs.

And cam wear is bad. Really bad. Worn lobes or tappets affect valve lift and duration, which reduces engine power and efficiency. In extreme cases, increased pressure can remove material from the lobes and deposit it in the oil, where it circulates through the engine and causes damage. Break-in helps harden the metal so it’s more resilient to wear.

That raises a critical question: How do we simultaneously allow controlled wear to the cylinder wall/piston rings while protecting the cam against wear? Those two tasks seem mutually exclusive.

In a word, oil

The solution is to use a properly formulated break in oil that allows controlled wear at the cylinder wall/piston interface, but that also protects the cam lobes and tappets from wear.

How do we accomplish this black magic?

Most break in oils, including AMSOIL Break-In Oil, use conventional base oils. Compared to their higher-quality synthetic counterparts, conventional base oils result in a thinner, less durable protective oil film on engine parts. The thinner fluid film allows controlled wear at the cylinder wall/ring interface.

But what about the cam? Won’t it wear, too?

ZDDP

That’s where anti-wear additives come into play. ZDDP anti-wear additives are heat-activated, meaning they provide wear protection in areas of increased friction. In this case, it’s at the cam lobe/tappet interface. The additives form a sacrificial layer on the surface of parts, which absorbs contact and helps prevent cam and tappet wear.

As a rule of thumb, a good break in oil should be formulated with at least 1,000 ppm ZDDP. At AMSOIL, we take it a few steps further; our Break-In Oil contains 2,200 ppm zinc and 2,000 ppm phosphorus.

How long does break in require?

Another rule of thumb states you should season a flat-tappet cam by running the engine above 2,500 rpm for 15 minutes.

As for seating the rings, our testing has shown it can take as little as seven dyno passes. That time varies depending on the engine, ring tension, cylinder hone and other factors.

If you don’t have access to a dyno, follow the engine builder’s or manufacturer’s recommendations. If none are provided, consult the recommendations on the break in oil label. In general, run the engine under light-to-moderate loads for about 500 miles. Again, that duration is a rule of thumb, but break in shouldn’t exceed 1,000 miles. Then, drain the break-in oil, install the synthetic oil of your choice and commence driving.

An engine dyno provides the best method of determining exactly when the rings are seated. You’ll notice a boost in horsepower as the rings seat. Eventually, horsepower will stabilize once the rings are seated.

Check out 5 Ways to Boost Horsepower for Under $500

You can also perform a leak-down test. Another, albeit more time-consuming, method is to remove the exhaust headers and check for oil residue in the exhaust ports. Presence of oil shows the engine burning oil, meaning the rings aren’t completely seated. Once the oil residue is gone, the rings are seated.

What about powersports engines?

Ask yourself a few questions about your motorcycle, ATV or other powersports application before using a break in oil:

  1. Does it have a wet clutch? If so, the break in oil may not be formulated for wet-clutch compatibility, leading to reduced performance.
  2. Does it use a shared sump with the transmission? Many motorcycles use one oil to lubricate the engine, transmission and primary chaincase. The churning action of transmission gears, especially in high-rpm applications, can tear apart – or shear – the oil if it’s not formulated to handle the stress. Using a break in oil not designed to handle high-shear applications can lead to damage.
  3. Does it have a dry sump? Some motorcycles store motor oil in a tank separate from the engine. Residual break in oil can collect in the system following the break in period and contaminate the service-fill oil. In this case, run the engine long enough to circulate the oil throughout the system and change it a second time to ensure the break in oil is completely removed.

Given the above challenges, we recommend breaking in a rebuilt powersports engine using the motor oil you’ve always used. Run it according to the original equipment manufacturer’s (OEM) new-engine recommendation, then change the oil. In short, treat it like a new engine from the factory.

For new engines, just follow the OEM guidelines. Typically they recommend a shorter interval for the first oil change to remove wear particles and contaminants from the factory. Then, change to the AMSOIL synthetic motor oil that’s recommended for your application and commence riding.