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356-930 356-930 is offline
Acceleration Junkie
Join Date: Aug 2007
Location: Laguna Beach, CA
Posts: 263
Originally Posted by Alan L View Post
, . . .my dizzy is a single port. . . . .
If it's a single port, it's vacuum advance and gets its air signal from below the throttle body. In application, at idle/high vacuum, the timing is "fully" retarded. Whenever the throttle body is opened and the more it's opened, the manifold vacuum decreases which advances timing.
Since your dizzy has no boost retard, it may have both low vacuum and centrifugal advance capacity (to limit advance at full boost).
You can check vacuum advance capacity at idle with a mini-vac and of course centrifugal/full advance at 3500-4000.
Your engine may truly benefit by use of the MSD 6AL and 8977 controller.
Sadly, as Nathan notes, improving performance via the MSD route is expensive but then what isn't expensive when it comes to a 930 and pushing the performance envelope?
Or, find a dual port dizzy which will buy you 8-11 deg of boost retard so you can get more aggressive timing when below boost threshold.
It may be beneficial to call Henry Schmidt, Supertec Performance, 760-782-3062 (San Diego, CA area) and inquire about a distributor that might accomplish the desired - he knows about these things.
Old 06-22-2008, 01:44 PM
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