Octane vs. timing.
Thread Starter
Drifting
Joined: May 2002
Posts: 1,546
Likes: 282
From: Back in Nebraska
Octane vs. timing.
I know that this octane, timing issue has been discussed a lot. But I need to ask a couple of questions. I timed my 1970 350/300 to 12* and 30* full on 93 octane no ethanol. If I try 91 or 89 octane will I have to retime the engine to run on that fuel? How will lower octane effect the engine temperature?
Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
Curious why you're wanting to drop fuel octane if you've got 93 availible. According to my manual, a 70' 350/300's 10.25 compression, which is quite high. If for some reason you do need to go down in octane, listen for engine pre-ignition pinging under acceleration. If getting it, pull a couple degrees of initial timing out at a time, until it goes away. Of course you're going to loose some power in doing this.
Thread Starter
Drifting
Joined: May 2002
Posts: 1,546
Likes: 282
From: Back in Nebraska
Curious why you're wanting to drop fuel octane if you've got 93 availible. According to my manual, a 70' 350/300's 10.25 compression, which is quite high. If for some reason you do need to go down in octane, listen for engine pre-ignition pinging under acceleration. If getting it, pull a couple degrees of initial timing out at a time, until it goes away. Of course you're going to loose some power in doing this.
Thread Starter
Drifting
Joined: May 2002
Posts: 1,546
Likes: 282
From: Back in Nebraska
