Briefly - as I'll hopefully see you at Japfest tomorrow.
My LPG installation is quite old and doesn't have the biggest injectors available so I'm limited to actuator boost only and not all the way to top RPM. It also misfires if you put your boot all the way down although it's not going weak. I suspect it needs uprated ignition to cope with igniting the LPG at full pressure.
The system I'm running is Prinz VSI with yellow spot kehin injectors. No 'valve lube'
I've fitted my aftermarket ECU and switching the dual map facility with a relay from the LPG system. This allowed me to run more ignition advance - which gave me a lot more ecconomy, power and improved drivability. It also allowed me to get the mixture map more accurate as the prinz just piggybacks off the standard ECU with crude corrections.
I've probably done well over 60K miles on the current engine (the one in the car originally suffered failed thrust washers, not LPG related). I've had to re-shim the valves once so far (probably at about 40-50K) as it was starting to run a bit rough and a couple of valves had virtually no clearance left.
Weigh up the relative cost of 'valve lube' per mile against the cost of a re-shim every 40K miles with maybe a head rebuild avery 100 - 150K. I'll go with the re-shim
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