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spuggy spuggy is offline
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Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 2,835
Originally Posted by gavinc69 View Post
JI'm starting to think the drumming noise is actually detonation and not the intake pipes on the rear fire wall!
I adjusted the boost retard to max just to see what happened and the drumming seamed to be less. I really need to get a timing light on it and check it out,
maybe need to adjust the distributor so it gives less total advance so the boost retard can dial out all detonation.
My suggestion would be to install a unit that not only provides programmable retard under boost, but also actively listens for detonation and adaptively retards ignition (per-cylinder) as necessary to control it.

The J & S Safeguard "universal" will do this in one box; I've had good results with mine.
'77 S with '78 930 power and a few other things.
Old 06-22-2013, 06:53 PM
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