High/Low Octane Spark Tables
Thread Starter
Teching In
Joined: Apr 2006
Posts: 7
Likes: 0
High/Low Octane Spark Tables What ultimately causes the PCM to switch between the high octane spark timing table and the low octane spark timing table? Does it initially try using the high octane table and switch based on the tendency to knock? If so, what makes it look back to the high octane table?
I am getting mixed opinions on other forums, so I opted to ask the experts.
By the way, the tried searching older threads but came up empty.
I am getting mixed opinions on other forums, so I opted to ask the experts.
By the way, the tried searching older threads but came up empty.
I uses a biased value between the two tables based on the knock learn factor. If it never sees any knock it would use the high table. The more knock it sees the more it migrates toward the low table. Sort of a blend between the 2 tables. The less it sees, it migrates back toward the high table. According to the HP Tuners people, they say it moves back up much slower than it moves down.
Originally Posted by 2xLS1
I uses a biased value between the two tables based on the knock learn factor. If it never sees any knock it would use the high table. The more knock it sees the more it migrates toward the low table. Sort of a blend between the 2 tables. The less it sees, it migrates back toward the high table. According to the HP Tuners people, they say it moves back up much slower than it moves down.
