Lawrence J-1 and J-2 were acquired by Wright Aeronautical in
1923. Wright's J-3 was a strengthened version of the J-2 and
their J-4 (now named the Whirlwind) introduced improved
J-5 introduced in 1926 had completely redesigned cylinders
with salt-cooled exhaust valves. The J-5
Whirlwind achieved sudden fame when it was used to power Charles
Lindbergh's "Spirit of St. Louis" to Paris in 1927.
The U.S. military designated this engine the R-790.