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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.

The RX8 was a great design but flawed motor. An Idea on Improving.

Solving the Utterly Useless Fuel Economy Issue in the Mazda RX8

An interesting blog & article on an amazing body and suspension. I’d own one now if I had the plan to make improvements. Perhaps one day..  Here are some clips from the post and the link so enjoy:

35 MPG RX8 by Paul Lamar

This is a method of downsizing the rotary engine for highway cruising. Right now the RX8 engine is running at about 3250 RPM at 65 MPH and getting 25 MPG. My guess it is using about 30 HP to go 65 MPH. That would be a fuel burn of around 2.6 gallons an hour or 15.6 pounds per hour or a BSFC of around .52. BSFC is defined as the number of pounds of fuel burned for every HP generated in one hour. Here is a very old BSFC map from a NSU Wankel rotary engine. No doubt the RX8 engine BSFC is considerable improved over this engine never the less the basic principles still apply. I don’t have a corresponding map for the RX8 engine in case you were wondering.

A turbo compound rotary could achieve a BSFC of about .38. Turbo compound engines use small turbines extracting HP from the 50% waste energy in a gallon of gas and feeding it back into the output shaft. A well known technology from the 1950’s used in airliner piston engines. One of the problems with these A/C engines was the failure of an exhaust valve would take out the turbine. Needless to say the rotary has no exhaust valves. The 8 HP turbine would be geared down by at least ten to one. Working backwards a BSFC of .38 would be a fuel burn for 30 HP of 11.4 pounds per hour or 1.9 gallons per hour or a MPG of 34.2 MPG at 65 MPH.

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