Mike Fortin sent us some pics of his personal conversion kit just released for existing O.S.91HZ motors. Check it out!!
The single most important engine upgrade you can do to an OS91 HZ is the new HZ-R conversion that has recently been released by OS Engines. After 6 years in the making both Steve Helms of Futaba/OS and James O’neal of OMI collaborated to what is clearly to be the best engine OS has ever produced.