400m pre-detonation?
Lead Driver
Joined: Jul 2017
Posts: 9,617
Likes: 1,185
From: San Jose, CA
New no longer means working unfortunately, so you can't ignore checking and re-checking even the newer, or brand new parts.
Question though, is did you break-in the cam before letting it idle or before messing with anything else? You may already know all about that, but many people still don't so I figured I'd bring up the subject right up front.
Since it was running correctly before we can at least assume that the firing order is correct, but other than the cam going bad you could easily have a vacuum leak developing, or plugs fouling or any of a number of things.
Might even be coincidentally losing your distributor's trigger mechanism. Easy to check with an Ohm-Meter though.
Ignition Control Modules not so easy to test though I don't think.
What induction and carburetor are you running?
Which distributor?
Might as well go down the list from the previous tests recommended in this thread.
Good luck.
Paul
Question though, is did you break-in the cam before letting it idle or before messing with anything else? You may already know all about that, but many people still don't so I figured I'd bring up the subject right up front.
Since it was running correctly before we can at least assume that the firing order is correct, but other than the cam going bad you could easily have a vacuum leak developing, or plugs fouling or any of a number of things.
Might even be coincidentally losing your distributor's trigger mechanism. Easy to check with an Ohm-Meter though.
Ignition Control Modules not so easy to test though I don't think.
What induction and carburetor are you running?
Which distributor?
Might as well go down the list from the previous tests recommended in this thread.
Good luck.
Paul
Logistics Pro
Joined: May 2010
Posts: 4,436
Likes: 19
From: Regina, Saskatchewan
New no longer means working unfortunately, so you can't ignore checking and re-checking even the newer, or brand new parts.
Question though, is did you break-in the cam before letting it idle or before messing with anything else? You may already know all about that, but many people still don't so I figured I'd bring up the subject right up front.
Since it was running correctly before we can at least assume that the firing order is correct, but other than the cam going bad you could easily have a vacuum leak developing, or plugs fouling or any of a number of things.
Might even be coincidentally losing your distributor's trigger mechanism. Easy to check with an Ohm-Meter though.
Ignition Control Modules not so easy to test though I don't think.
What induction and carburetor are you running?
Which distributor?
Might as well go down the list from the previous tests recommended in this thread.
Good luck.
Paul
Question though, is did you break-in the cam before letting it idle or before messing with anything else? You may already know all about that, but many people still don't so I figured I'd bring up the subject right up front.
Since it was running correctly before we can at least assume that the firing order is correct, but other than the cam going bad you could easily have a vacuum leak developing, or plugs fouling or any of a number of things.
Might even be coincidentally losing your distributor's trigger mechanism. Easy to check with an Ohm-Meter though.
Ignition Control Modules not so easy to test though I don't think.
What induction and carburetor are you running?
Which distributor?
Might as well go down the list from the previous tests recommended in this thread.
Good luck.
Paul
Two more questions to ask:
1) What grade of fuel are you running (87, 89, 91 octane)?
2) What is your timing set at (total timing)?
These two points were covered above, but not in great detail. Fuel octane and timing matter A LOT when it comes to detonation.
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