My Spit regularly sees 5700 RPM on an engine that is supposed to run on
leaded but only ever sees premium unleaded. Tempting fait? Well 3000 miles
sofar and not a sign of Valve seat recession. I reckon that my valve guides
will be what makes me take the head to the shop.
Anyway, the engine does not take to red line chases very well unless it's in
good health. Let's face it, even low mileage cars the valve springs are
passed it, because they have been laid up with one or two springs
permanently compressed.
Replacing the springs with the UK spec 1500 double valve springs will lead
to much less valve float, and better red line.
You carburettors not only have to be synchronised at idle, but you must then
adjust the linkage to synchronise them with the throttle. I.e. when you
give it a squirt both dampers reach the same high. They both need to be
perfectly in tune, it's possible to have one two rich and one two lean
which can be horrible to sort.
Generally shift lower on first than any other gear, because you want a long
pull in second. My stock Spit reaches 60 in about 11-12 seconds, but it's
the one with the most torque, (MK 3 has 2 more BHP) UK Spit 1500.
The other component that can cause you hassle is your distributor, best to
have your old one overhauled, and at the same time convert to magnetic
pickup ignition. Optical I have heard horror stories about having to keep
them clean. Magnetic you can run with crued oil in there if you want!
Basically the points wear the distributor oval, and reduce the shaft
diameter, you get major float, mine floats about 4 degrees at the higher
Rpm's. Not to mention problems with the points at those speeds.
With old age these engines become lazy plodders, which with abit of TLC and
fettling can be made to feel like teenagers again.
James
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