Engine Knock upon Quick Acceleration
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Joined: Sep 2019
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Engine Knock upon Quick Acceleration
I have a '70 w/ the 350/350 hp engine. If I drive it cautiously, I don't have any problems. But upon quick acceleration, I get serious engine knock. (you know marbles in a coffee can sound). Do I have to run an octane booster, or can I retard the engine timing? Even though I run the highest octane gas (93), I'm wondering if any pump gas can work w/ 11:1 compression ratio. Footnote: where do I hook up the pos and neg leads on the timing light?
Melting Slicks
Joined: Apr 2019
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From: Northern Wisconsin
Since you are already running 93 octane, you will probably have to retard your timing enough to make the knock go away. Hopefully you won't take much of a performance hit along with that. The positive and negative leads of your timing light can be connected to your battery if it is readily accessible.
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Positive on the back of the alternator or you buss bar on the horn relay. I have a ground on my alternator, I use it. Check you air fuel ratio when you first mash the pedal, it should be down at 12. If you can’t your only alternative is to retard the timing until it goes away. Then read Lars paper to see if you have too much timing in it and adjust as necessary
Last edited by Rescue Rogers; Jun 19, 2020 at 12:10 PM.
