2.6 Smoothbore 5.9L 12-Valve Cummins Engine - Engine Builder Magazine

2.6 Smoothbore 5.9L 12-Valve Cummins Engine

With fewer open class pulling events occurring due to COVID, Tim Richardson decided to change his 12-valve 5.9L Cummins engine to fit the sanctioned 2.6 class pulling rules. Find out what went into the rebuild.

Diesel of the Week is presented by

Like many folks who make engine building a career, Tim Richardson found an affinity for diesel when he was in high school. He had a ‘91 Dodge truck that he swapped a Perkins diesel engine into. He found an adapter plate to bolt the Perkins to the transmission in his Dodge, and despite the power level not being quite what he wanted, Tim was hooked.

“The Perkins didn’t have the power or the performance ability I was really after, so a few years later I bought a Cummins first Gen and started working on it and my passion for diesel evolved out of that,” Richardson says. “People saw that I was working on mine and they started bringing me theirs and the next thing you know I’m really busy with diesel work. I worked two years in the diesel injection industry. I learned the diesel injection side of the 12-valve and primarily Cummins engines. Then, I started my shop in 2009, building high-performance engines for other people.”

That shop is called Richardson Diesel, located in Bidwell, OH. Tim runs the shop along with help from his two sons, and does everything in-house for 12-valve and 24-valve Cummins engines. The shop builds its own injectors, pumps, turbochargers, engines, and more.

“I’m really hands on with it,” Richardson says. “That’s the reason I’ve stayed primarily with the 12-valves is because I don’t have to outsource tuning and all that other stuff. I do 24-valve and 12-valve Cummins engine work. I do some electronic stuff, but I really like the mechanical platform.”

One such example is Tim’s own 2.6 Smoothbore 5.9L Cummins engine in his shop truck – that ‘91 Dodge. This particular engine had previously been built to run in the Brush Pulling open class with 1,500 horsepower on hand. However, as COVID has affected many things, pulling events included, Tim says he’s had a tough time finding pulls to compete in. His solution was to move to the sanctioned competition of the 2.6 class.

“The problem we’re having trouble with right now is finding pulls with COVID because county fairs are not investing the money into pulling,” he says. “Switching to the 2.6 platform, I’m finding pulls that I can go to. That’s the main reason for the rebuild. We scaled it back to run the 2.6 because that’s a sanctioned pulling class and it’s getting hard to find pulls otherwise.”

Richardson says he built this engine with a few upgrades to fit the different rules of the 2.6 class, and started the build with a ‘95 Cummins 12-valve block.

“The block has been line bored and it’s got cam bearings in it and the block is filled with hard block,” he says. “The crank is still an OEM polished Cummins crank. Nothing has been done to it other than it’s been balanced, polished, I added oil clearance to it, and it has Haisley Clevite H-series coated bearings. It’s got a set of Apex Diesel billet rods in it. I’ve worked with Haisley (Machine) for years, so it’s got a lot of Haisley parts in it.

“The engine is still a standard bore 5.9L Cummins. It’s got Haisley studs and a Haisley girdle in the bottom end of it, and it’s got a set of custom Haisley spec Ross Racing pistons. In addition, it has a Hamilton billet steel camshaft and a Hamilton cylinder head that was ported by me and a good friend of mine. We ported the head and did all the valvetrain work.”

Speaking of the valvetrain, Richardson utilized a set of PBM valve springs for a big block gas application, but machined the head to accept them. It also has Hamilton oversized valves, Manton tool steel pushrods, Hamilton billet tappets, and the injection pump is a Farrell Stage 6 13mm injection pump.

“For the injectors, those are a different combination,” he says. “They are a Harts diesel billet body with a nozzle that I designed. I found some more power in my nozzle. I’ve built a lot of injectors with the 12-valve and have really learned a lot over 15-18 years with the 12-valve power.

“The engine also has Haisley Machine L19 head studs. It has a Haisley Machine billet front cover. We’re still utilizing the stock rockers because I’ve had good luck with them. It also has a Fluidampr and it runs a Valair triple-disc clutch on the back of it.”

As of now, the engine is still waiting on a turbocharger before it’s completed, but Richardson hinted that it would likely be an Apex turbo. As for the truck itself, it’s a 2001 chassis that’s been completely braced and fabbed for pulling on top of a ‘91 Dodge body.

“It’s the original truck I started with,” Richardson says. “I’m putting that body on the late chassis. It’s a full one-off build for pulling.”

This one off build, with some changes to make it 2.6 legal, will be shooting for 1,100 horsepower when it’s all said and done.

Diesel of the Week is sponsored by AMSOIL. If you have an engine you’d like to highlight in this series, please email Engine Builder Editor Greg Jones at [email protected].

You May Also Like

Turbocharged and Nitrous-Assisted 6.8L Cummins Engine

Ryan Milliken and Rod MacMaster teamed up to build a diesel-powered Corvette to compete with the best of the PDRA Pro Boost class. Thanks to Freedom Racing Engines and Midgets Diesel Performance, among others, the turbocharged and nitrous-powered 6.8L Cummins engine was showing great signs of success. However, its now back to the drawing board for this Diesel of the Week.

If you follow Ryan Milliken and Hardway Performance on social media, you already know Ryan is a busy guy who gets to do some very cool things with diesel vehicles. Not only does he campaign his own Cummins-powered Chevy Nova with some great success, but he helps others reach new heights within the performance diesel world.

Turbocharged 7.3L Powerstroke Engine

Every year, there’s hundreds of diesel trucks at the Ultimate Callout Challenge. As expected, most feature 6.7L Cummins engines, but that’s what makes seeing a Powerstroke build that much more special – let alone a 7.3L. We were able to find one built and owned by Corey Hurtts of CNC Fabrication. Check it out!

Compound-Turbo 6.0L Powerstroke Engine

Did we expect to see a 1962 Ford Country Squire at a huge diesel racing competition? No. Were we inevitably hyped up when we saw one at the 2023 Ultimate Callout Challenge? Hell yes. This one has a beefy 6.0L Powerstroke swapped under the hood making it a kickass combo worthy of our Diesel of the Week!

6.0L Powerstroke Swapped Mustang

Tyler Hewett’s clothing brand “Anti Cummins Swap Club” will tell you all you need to know about him… so will his 6.0L Powerstroke swapped Mustang. We got to see it up close at the 2023 Ultimate Callout Challenge. Check it out!

Compound-Turbo 5.9L Cummins

Cancer Sucks! This Chevy S10 from the guys over at Stainless Diesel not only packs a punch with it’s compound-turbocharged 5.9L Cummins, but promotes the awareness and fight against the deadly disease.

Other Posts

Cancer Sucks S10 with a Compound Turbo 5.9L Cummins Engine

It’s hard to miss Stainless Diesel’s #CancerSucks S10, which features a compound turbo 5.9L Cummins engine. During the 2023 Ultimate Callout Challenge, we caught up with Steve O’Neal to get the details of this special truck and it’s Cummins powerplant for our Diesel of the Week. Related Articles – Sandy Wilkins Invites Us to Tour

Amsoil Launches New 10W-30 Commercial-Grade Diesel Oil

AMSOIL has added a 10W-30 diesel oil to its Commercial-Grade family of products. New AMSOIL 10W-30 Commercial-Grade Diesel Oil is designed for those seeking an upgrade over conventional and other synthetic-blend oils in heavy-duty equipment and vehicles. It is a synthetic-blend product with greater than 50% synthetic content to help keep trucks and equipment operating

Turbocharged and Nitrous-Powered 6.0L Powerstroke Engine

At this year’s Ultimate Callout Challenge, we ran into more folks just starting to get into racing their diesels than we have in the past. One such racer was Connor Wagner of Wagner Diesel Solutions. His shop specializes in the Powerstroke platform, so he decided it was time to start showcasing what he can do

Mitchell Wicklund’s Turbocharged 6.7L Cummins Engine

During the 2023 Ultimate Callout Challenge, the boys from Maverick Diesel were busy in the pit area with two different trucks they brought to Indy. One of those trucks was Mitchell Wicklund’s with a turbocharged 6.7L Cummins engine in it. We spoke to Mitchell about the build done by LinCo Diesel Performance. Check out our