>The real performance advantage of an electronic distributor is that
>there is no variation in spark timing coming from variations in point
>lobes - since there are no points. Is this better than a point
>distributor? Only if there is something wrong with the point type
>distributor.
My immediate thought is: Given that all else is equal (I agree with your
argument here), the electronic distributor/ignition is better because
there are fewer parts to wear out, lose adjustment, etc, etc.
>I didn't say that 0.045 was a useful limit. I was implying that above
>0.045 can cause breakdown of ignition system components and introduce
>certain driveability problems. I gap mine to the gap the spark plug,
>engine, and ignition system was designed to run at and look elsewhere
>for gains in performance or driveability.
>The question about "why then did the new cars go to wider gaps (ie
>0.045)" is a really (really, really) good one.
I gotta go with your theory on this (emissions, et. al. causing leaner
running engines requiring a stronger spark). Had a '74 Olds Cutlass at
one time with one of the first HEI systems -- plugs were gapped at .080,
but my '78 Chevy half-ton requires a gap of .045.
>Made me go hmmmmm for a while....
What makes me ponder is that the gap on my '79 Midget is supposed to be
set at .025 -- I think that this is the same gap as every other Midget
produced (preceding and through the nastiest of the emmissions years)....
This one has a electronic ignition, unlike earlier models, but has the
"point type" coil. Perhaps this is the difference?
My first car was a '66 Chevelle with a 230 CID straight six and a
PowerGlide; points ignition and .035 gap on the plugs. I read about
indexing plugs and trying different gaps and did this while leaving
everything else the same. Mileage improved a bit (maybe 2-3 miles to the
gallon) but I don't recall a change in performance (although I doubt I
would have seen noticeable change on a tired six cylinder....).
My conclusion: I think, then, that one should one use the spark plug gap
as another setting to optimize, right along with heat range, type, etc --
after all else has been fixed. Individual driving requirements,
weather, and equipment suggest that this is one variable that, like
jetting a carb, can effect the overall drivability of your car even if
you have optimized everything else. YMMV.
Les, how about an update on that V6 Spridget of yours?
Rich
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