> Hi, Randall. It was the "Triumph Owners Handbook of
> Maintenance & Repair,"
> Floyd Clymer Publications, Los Angeles (no date), page 10,
> where it states:
> "The following valve tappet clearances are recommended for
> the TR-2, TR-3
> and TR-4 as listed below. Measurements are made with the engine cold.
>
> "TR3-4: Intake .010, Exhaust .010. HIGH SPEED: .013 inches
> for both
> intake and exhaust TR2/3/4
Interesting. Thanks for the reference.
The factory statement (Practical Hints, 4th ed I think) is "Where aluminum
rocker pedestals are fitted (later models) the valve-rocker clearance should
be set at .010" inlet and exhaust for both normal and high speed motoring.
> "The .013-inch clearance will give a noticeable increase in
> performance in
> most cases
Might improve low-rpm torque, but at the expense of high-rpm power. What it
does is reduce the valve duration slightly, giving the effect of a milder
cam. Most tuners go the other way ...
> I'm not a good mechanic, just good at following directions,
> so forgive the
> queastion: Isn't reducing valve float going to enhance performance?
Sure, if valve float is happening. With the later components it didn't
usually happen.
> I think next time I
> readjust the valves, I'll take the nuts completely off and
> down to the
> hardware store to match the threads with hopefully a
> stainless or case
> hardened nut, because I think what I've learned from you this
> time is that
> the threads are standard, and that's good!
The threads are standard, 5/16-24 I'm pretty sure; but the factory nuts are
shorter than standard nuts. Full height nuts will make the screwdriver slot
harder to get to. And by adding mass to the valve train, you will aggravate
valve float <g>
> I do have a
> work around,
> which is simply to mill the slot out a bit bigger. Just
> don't like to do
> that kind of thing without tracing the issue to it's core.
In addition, you'll have to do it again every time you buy points. Might be
worth finding another dizzy to compare measurements with ... if nothing
else, they frequently sell on eBay for $10-$15.
Randall
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