To my surprise, after doing tests on two engines: dle-55 and dle-111 using redline oil and ACE synthetic oil, here are the results,
DLE 55 (on an extra with fair air ventilation)
Redline: temp range 96-106
ACE: temp range 86-96
DLE-111 (on a yak - no baffles used)
Redline: temp range 122-130!!!
ACE: temp range 98-118
Temps are in Celsius.
Conclusion: In general the ACE oil gave a 10-20 degrees difference!!! in both engines
Note: for the dle-111, I checked the needles and the low was 1 turn while the high was 3/4 turn. This is a difference of minus 1/4 turn for the low and 3/4 for the high!!! I think it was too lean. The reason I got this lean was to raise the RPM to 6000 (it was around 5400) plus the engine was spitting black oil residue so I thought it could have been too rich!
Now I am confused:
1- Is ACE oil better than Redline?
2- Was the dle-111 too lean? I guess 130 is too dangerously high temp!!
3- Are there any factors other than engine temp to gauge the quality of an oil?
Thanks in advance!
Note: I searched for the ACE synthetic oil in the gas engines forum and did not find a single trace of it!!! Anyone heard of it ?