We also have a 1980 Turbo Arrow IV with Gami injectors. We have a JPI EDM-800 Engine Monitor and use it to run the engine Lean of Peak. We use the Lean Find feature in Lean of Peak mode. Our plane also has an Airflow Systems Intercooler and Merlyn Wastegate.
First we pre-lean our hottest cylinder to 1530 degrees EGT. We do this by watching cylinder #4 which is always our hottest. We wait a minute for the temps to adjust. Then we put the EDM 800 into Lean of Peak mode and slowly lean until all the cylinders peak. Then wait for the temps adjust again. If any cylinder EGT is over 1600 degrees we lean a bit more to cool it off. This generally gets us about 10.2 gph fuel burn and around 62% HP at 10,000 feet. Cylinder temps are low 300’s to high 200’s and EGTs below 1600.
