The Pinnacle V6 Ecoboost Shortblock for your Big Turbo Builds 
RMB 4.2L Stroker Stage 3 Short Block
By adding a billet stroker crank to our already potent 3.5L Ecoboost engine we have raised the bar. When changing to larger turbos there is always a tradeoff of low end grunt for increased top-end power. To remedy this, our 4.2 liter RMB Stroker Engine increases displacement by a tick over 20%!!  What does this equate to?  It adds horsepower and most importantly asphalt shredding torque. The increased stroke coupled with an elevated compression ratio produces more low end torque which considerably reduces turbo lag and improves boost response. The RMB 4.2L allows you to now have your cake and eat it too!
Big Benefits, No Compromises
To improve the output of your V6 Ecoboost, we raised the compression ratio a hair to increase horsepower throughout the powerband. This increase also produces more low end torque which reduces turbo lag and improves boost response, while still only requiring 93 pump gas.
The Perfect Combination 
This new 4.2L power plant uses only the best off the shelf and custom designed RMB spec. components. Combine that with the latest in machine and assembly practices and you are assured you get the RMB Spec quality!
Not Your Standard Off-the-Shelf Rotating Assembly
RMB worked closely with our manufacturing partners to specially design engine components custom to our engine program. The RMB custom JE Pistons feature improved oiling characteristics, newest Perfect Skirt ***TR** coating for reduced friction of skirts, latest En Nickel coatings, and more. The Custom Connecting Rods being made of a 300M forging are sure to let you get as rowdy as you’d like. 
Our Race Winning Experience Creates Higher Standards
To further improve the RMB 4.2L  platform every Short Block is precisely balanced, and hand assembled to RMB’s exacting standards. Before assembly each block is checked for correct dimensions, cylinder bore, mains, block flatness, etc… to guarantee you get the best foundation for your new engine.
Do it right the first time, order your RMB 4.2L Race Short Block today!
 Exclusive Benefits
 
 
Custom RMB Billet stroker crankshaft for added torque
Increased compression ratio for added horsepower and torque
Reduced turbo lag and improved boost response
RMB proprietary components for the strongest, most advanced engine program available
Balanced rotating assembly
Precise, documented hand assembly
Custom compression ratios available
Applications
 
2011-2016 Gen 1 Ecoboost 
2017+ Gen 2 Ecoboost