[alfa] Followup on Spica low fuel pressure symptoms

[Kevin Trent <trentkc@xxxxxxxxxxxxxx>]

Back on April 11 (V10#31) I described a chronic fuel pressure problem on my 
Spica injected Berlina:
"The Berlina was heavily loaded and we were driving @ 4000 rpm on the 
interstate.  The
fuel pressure warning light was on, and after 80 miles the very slight 
hesitations turned into an inability to maintain speed.  We limped to the 
nearest town with an auto parts store, and I purchased two feet of 3/8" 
fuel line, then replaced the fuel tank to fuel pump fuel line which 
eliminated the tank filter which I was hoping was clogged.  Fortunately, 
this fix worked, and we were able to complete the rest of the trip at speed
with no further problems, although the fuel pressure light did light up 
occasionally under heavy load."

I cured this fuel pressure problem by applying the fix that has been in the 
public domain for many years, best described in the AROC Technical Notes 
Series on the Spica Fuel Injection System (Di Matteo & Hertzman, P64). 
Basically, the fuel outlet nipple on my pump had the larger size orifice of 
3/32 instead of the recommended 1/16.  The fix was pretty easy - I just got 
a butane torch and heated up the nipple (front nipple on the pump) after I 
removed it from the pump, then dripped plumbing solder onto the back side 
of the orifice, then kept the heat on the nipple for a good bond. After it 
cooled, it was easy to drill the orifice out with a 1/16 drill.  Visually, 
there is not a lot of difference between 3/32 and 1/16, but the sq. area is 
about half.  I've put 300 miles on the Berlina since the modification, and 
the fuel pressure light has not come on under any hard driving 
conditions.  The engine also seems to run better at high RPM and heavy 
load, with no hesitations as I approach redline.

//kct, Powell TN  (Now thinking of trying those relays for the headlights..)
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