Hi Everyone.
My patrol has multiple flat spots between 1000 to 2000 revs when under load. The vehicle runs well over 2000 revs and has done many good miles on the open road. This has been an issue for an extended time and been serviced by many people to no avail. The engine is RB 30 with a gas conversion, manual transmission. Apart from the gas conversion, no other modifications.

Initially I thought it was carby issues and did a complete dismantle, clean and service kit with no improvement. Realised then that the issue occurred on gas as well implying that it isn't a blockage in the carby. It is worse on gas and improves with higher octane fuel.

Checked all vacuum lines are correct. Found a faulty vacuum advance unit and replaced it. Also found centrifugal advance was sticky so cleaned and freed up that. Still no luck. All high tension leads are good and plugs have been replaced several times in the process.

I hope the brains trust out there can offer some suggestions because it has got me beat.
Regards,
Lionel