Mack's New Granite Gets 540 HP MP13 Engine with Over 630 Braking Horsepower
Mack Trucks unveiled the EPA27 MP13 engine for its Granite model, boosting horsepower to 540 and braking power to over 630 hp.
540 hp
Over 630 hp
Over 20%
What Happened
The EPA27 MP13 engine features a higher compression ratio of 20:1, a new turbocharger with ball bearing wastegate, and a seven-wave piston bowl for better fuel atomization. These changes increase horsepower to 540 and improve engine braking by over 20 percent to 630+ braking horsepower.
“When you’re in a loaded dump truck going down a 30 percent grade and it just walks you down, its impressive. I believe it is one of the best engine brakes we’ve ever had.”
- 505 hp
- Over 630 hp
Why this matters
The new engine helps Mack meet the EPA27 emissions standard while delivering significant power and braking improvements, making vocational trucks more capable on steep grades and heavy loads.
Terms in This Story
- EPA27
- EPA's 2027 heavy-duty engine emissions standard for reduced nitrogen oxides and particulate matter.
- compression ratio
- The ratio of the cylinder volume at the bottom of the piston stroke to the volume at the top.
- mDRIVE
- Mack's automated manual transmission that handles shifting without driver input.
- turbocharger
- A device that uses exhaust gases to force more air into the engine, increasing power and efficiency.
Summarised from the linked release; details can be imperfect — always verify against the original source.