Sorry to say it but the holden engine is not going to help your cruising - a bad engine choice. The rev characteristics are all wrong for the landie gearing - landie engines have a flatter torque curve than holden engines so when cruising the holden engine will have to rev higher than its 'sweet' spot - basically it will be reving at a level where torque is tailing off.
You might want to have a rethink -even a good 2.25 petrol landie engine works better than a good holden engine with standard landie gearing.
Garry
REMLR 243
2007 Range Rover Sport TDV6
1977 FC 101
1976 Jaguar XJ12C
1973 Haflinger AP700
1971 Jaguar V12 E-Type Series 3 Roadster
1957 Series 1 88"
1957 Series 1 88" Station Wagon
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