Can you fit a 4 1/2 bore cylinder in an old 7j or 4g RD4. I know they came with 4 1/4 but just wondering if anyone has tried it. I know cat made a few
D4's with a D6 engine. I think they called it a D5. Saw one up a Jim Zimmermans last winter. I suppose bigger injectors would be neccessary. Thanks
John