Hi Guys
Whilst I do not want to openly refute one persons claims about what worked
for them with this particular issue I feel that I have to comment. In my
opinion you will not notice any change in the performance of your stock TR
engine by indexing the spark plugs, but, that is not to say that it does not
work, for I know for a fact that it does! The
key word is STOCK. An engine that is tuned to the ultimate degree will
benefit from indexed plugs.
Some 10 years or so I had the fortune to run a small historic Grand Prix
team. The plugs were indexed and under dyno cell test conditions the HP went
up. The percentage of increase was miniscule but we did it anyway. I here
you ask "if it is so small an increase why do it?" I can give you more
examples of thing we also did to gain the 'edge' as we would call it, change
tire temperatures prior to the race, change the headers and intake manifolds
depending upon the barometric pressure and humidity, change thermostats,
change cooling fan cut in temperature. Change the engine oil specs. Change
cam timing and duration depending upon altitude and weather conditions. In
those instances that miniscule amount of gain could make a difference
between being first or third.
I know some people n the drag race world that depend upon getting that last
minute portion of HP just to stay competitive, where the jobs they have
depend upon 1 one hundredth of a second. That small amount will count at
those times. In a daily driver TRIUMPH I think not.
If you have done it and it works for you on your stock TR then well done,
you have done a great job and I hope you enjoy driving your car for many
years to come.
BTW If you have access to a 4 gas emissions machinery, open the spark plug
gaps to double the normal setting and check the results. We used that as
well! and even used odd plugs in different cylinders to aid cylinder
cooling.
Regards
John J Black
Waterloo Drivetrain Systems
www.waterloo-dtr.com
-----Original Message-----
From: owner-triumphs@autox.team.net
[mailto:owner-triumphs@autox.team.net]On Behalf Of CarlSereda@aol.com
Sent: Wednesday, April 12, 2000 9:53 AM
To: triumphs@autox.team.net
Subject: Indexing SparkPlugs-HallaBaloo?
Hi List,
Just wondering about this recent topic (getting more horses from a TR6
motor)
of indexing the spark plugs (shimming the plugs so that electrode faces open
toward inlet valve for more efficient combustion... Has anyone witnesssed
better combustion using this technique with their Accu-View tune-up kit?
It sounds like a reasonable fine-tuning adjustment but how come the Moroso
company that sells the sparkplug shimming tool doesn't mention efficiency of
combustion - only that the shims are for adjusting depth so your pistons
don't smash into plug tips on high compression race cars...
Any more evidence this is worthwhile effort for our basic motors?
Carl
'64 TR4 since '74
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