John Revill
Active Member
- Joined
- Feb 7, 2018
- Messages
- 116
- Reaction score
- 61
- Points
- 28
- Age
- 52
- Location
- Jordan Springs NSW
- Members Ride
- WN Caprice V 6.2L A6
Both the 6.0L and 6.2L engines will degrade performance if they detect knocking in the engine. This will almost definitely happen if you run 91. Even E10 is better than 91 (usually 94). 95 at an absolute minimum for these engines. If you want performance, go with 98 in the LS3 6.2 and even better if you can get it is go E85 (107 octane) on the L77 6.0.
Another factor is Intake Air Temperature. The hotter the air going into the engine, the more timing advance that is taken out, even if knock is not detected. This is why cold air intakes work so well on these engines.
So in Summer running 91, the car will probably run crap.
Another factor is Intake Air Temperature. The hotter the air going into the engine, the more timing advance that is taken out, even if knock is not detected. This is why cold air intakes work so well on these engines.
So in Summer running 91, the car will probably run crap.
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