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Overdrive Almost Ready


Luke Skywalker
Country flag
I know, big deal. It's only been 6 months.

OK it's done and bench tested. Perfect at about 375 psi which is the recommendation per VTR for the older heavy accumulator spring. Big relief.

I'm ready to set the OD operating valve lift, and the "Articles" say the steel ball lift beneath the plug should be about .016. There are some differences of opinion.

If I use the adjustment lever as the guide--lining up the hole--I get .025.

Any opinions on which go with. Obviously, .016 is a smaller ball lift.

Also, if I bench test the solenoid do I just go straight to + current of a battery with the yellow and yellow/purple wires, connecting them together or do I need to remove the relay from the car and use that somehow?

From one continent to all others, across the hemispheres, from the arctic to the Cape of Good Hope and over to Cape Horn, I have a hunch who may have these answers.



Jedi Warrior
Not who you were thinking of but I can help. Ground the transmission case and plus to the solenoid wire will activte the solenoid.


Great Pumpkin - R.I.P
I'd also go with the adjustment lever setting. .016" is too small anyway, in my opinion. .025" is just about right.

Contrary to what others have asserted, I do not believe that Laycock/Triumph ever expected the valve opening to control how fast/hard the OD engages. When they wanted a softer engagement, they reduced the displacement of the accumulator.

But the early units were supposed to engage hard. I even have a Laycock brochure that quotes a customer comparing it to a mule's kick.



Darth Vader
Bam is right especially with the A type, and Bam is the sound your rear end will make if you are not careful

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