Rob asks: (Datsun 2000 w/Hatachi SU's)
>The problem is closing the throttle does not result in an immediate
>drop in engine speed.
British SU's got an emmissions mod after '67, which I suspect might be
what you have. The Throttle plate has a smaller, spring loaded plate
which is designed to open when the throttle is closed, allowing some
air to enter so as to prevent the otherwise rich resultant mixture.
This results in a slow throttle off response. (Boo, hiss) The ecological
thing to do is leave it as. The performance thing to do is replace the
throttle plates with earlier, solid ones. You can also solder the valve
shut, but this isn't quite as good, as it leaves more restriction in
the air path, and _could_, (remote chance) come unsoldered if you had
a good, hot backfire, and get sucked into the engine. (Use a propane
torch, *Clean* plates, rosin core solder). I suppose you could try and
braise them, but the required heat might melt/distort the plates if
you're not careful.
[This advice is warrented for 90 days. If, within 90 days, it is no longer
advice, you may return it]
________________________________________________________
Roger Garnett (garnett@tcgould.TN.CORNELL.EDU)
The South Lansing Centre For Wayward Sports Cars
"All donations of stray, orphaned, odd, neglected, etc.
sports cars and bits in need of a good home accepted."
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