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Discussion Starter #1
I've seen in a couple of places that to start tuning the mixture for a SPICA, you close the FCS ring screw all the way, then back off 6 turns, or something like that.
I have the '69 SPICA version with the small mixture screw on top (no FCS). Is there a similar rule of thumb of where to put this screw's travel for a starting point to set the mixture ?

Cheers,
Jeff
 

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Jeff,

If the car runs, you're already at the starting point. Do you have a copy of Wes Ingram's SPICA guide? (highly recommended http://www.wesingram.com/). This outlines setting the fuel mixture both with and without an exhaust gas analyzer. For without; hold engine speed at 2500 RPM and turn richness in or out to obtain highest engine speed. Then lean the engine until it begins to slow down. Next, richen until it again slows down. If you marked the position of both extremes the correct micture is halfway between. BTW, for all pumps except 1969, the fuel cut off solenoid is turned clockwise to lean. For 1969 pumps, turn the mixture screw counterclockwise to lean mixture.

To repeat advice from Wes, Don't start messing with the mixture unless you have completed all previous steps in the tuning sequence. I can't emphasize how important this is; I had some tuning issues last year and Wes emphasized "Go back to the basics". I could not solve my problem until I went back and corrected a setting I was convinced was correct (it wasn't).

I've seen in a couple of places that to start tuning the mixture for a SPICA, you close the FCS ring screw all the way, then back off 6 turns, or something like that.
I have the '69 SPICA version with the small mixture screw on top (no FCS). Is there a similar rule of thumb of where to put this screw's travel for a starting point to set the mixture ?

Cheers,
Jeff
 

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George is Correct.

You have to start at the beginning of the process, as outlined on this board and by Wes' Spica book.

Each adjustment is dependent on its' predecessor.
 

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Discussion Starter #4
You guys are right of course. I just installed a pump Wes rebuilt. Actually I've done Wes's procedure very carefully up to the point where the mixture is adjusted.

Car idles very rough. I accidentally found it smoothes out nicely if I push the long rod down (with it disconnected from the relay crank) which opens the gap. I was looking to keep from continually bombarding Wes with e-mails...

Cheers,
Jeff
 

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I had an idle problem with my '76 Spider sporting a nice shiney Ingram HP pump and my tale may offer some insight into your problem: At the Tulsa convention seminar, Wes Ingram emphasized the value of an adjustable timing light (the kind where you center the timing mark then read the degrees on a dial at the end of the light). my problem was that the advance range had worn on the distributor; if I set idle correctly, the total advance was 43 degrees, but If I set the total advance at 37/38 degrees, the idle was way off (retarded) and the engine didn't want to run.

I found the problem by using an adjustable timing light (around $70.00 at Sears). I solved the problem by sending my distributor to Wes for rebuilding and setting the advance curve to fit the modifications I had made.

You guys are right of course. I just installed a pump Wes rebuilt. Actually I've done Wes's procedure very carefully up to the point where the mixture is adjusted.

Car idles very rough. I accidentally found it smoothes out nicely if I push the long rod down (with it disconnected from the relay crank) which opens the gap. I was looking to keep from continually bombarding Wes with e-mails...

Cheers,
Jeff
 
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