Don Terrill’s Speed-Talk

Help! Someone recently (2-3 days) posted a pic/reference to digital tool (sort of like the old P&G Valve Gapper) as per title. I though it was from "Precision Instruments" or some such. I'm having zero luck with the Search function since the site revamp and can find nothing about it.

Thanx in advance.

OK, found it! (In Harold Bettes' new Flow Measurement book): Precision Measurement Supply. Looks to me like it could expedite a new method of checking lash: Rotate the engine slowly through the valve seated range, wiggling the rocker arm up and down as you go. The max gauge reading is the lash; no worrying if you're fully on the base circle of if it has runout.

MadBill wrote:OK, found it! (In Harold Bettes' new Flow Measurement book): Precision Measurement Supply. Looks to me like it could expedite a new method of checking lash: Rotate the engine slowly through the valve seated range, wiggling the rocker arm up and down as you go. The max gauge reading is the lash; no worrying if you're fully on the base circle of if it has runout.

I looked on their web site and am not seeing it. Do you have a link for the tool?

Bill, did you ever hear the story about the P&G gapper when the inventor took it to Iskendarien and demanded he try it? What he really wanted was an official endorsement. Ol' Ed told his machinist to set the valves carefully per the P&G directions, on an unblown Chrysler drag engine that happened to be on the pump. They did a dyno run & logged the results. Then Ed said, "now, set the valves quick and sloppy like we were at the track & you only had a few minutes between rounds" As you may have guessed, the second dyno run showed a few % GAIN in power. The P&G guy left shaking his head. Point is, sometimes real precision settings mean less than getting a combination that works for your machine. I wouldn't spend extra for a microprocessor to tell me if a motor was lashed right, personally. I'd set it, run it and if it needs a tweek, I accept that. Engines are female, I'm convinced!

I think it would be a nice tool to have.
Nice to check base circle run out with the other pushrods installed as compared to without to see how much your cam moves from spring force.

If I was Ed, I'd have wanted to use the valve gapper to determine exactly what lash resulted at each location from the quick 'n dirty adjustment, since it was obviously better than the spec setting...

Is this the lash tool yall are talking about, or is there an electronic version available?

http://www.precisionmeasure.com/valve4.htm

Thanks!

John

That's the one. I misremembered that it was dial Vs. digital when I posted the thread. (and FWIW, it is essentially identical to the old P&G device)

I was shown once that you can really narrow your window of feeler gauge “feel” by how you hold it.
You hold it by the sides, or the way it would cut your fingers if it was thin enough. It magically becomes a better gauge for gauging size.
Think paper cut and it will be clearer.
I can’t see the need for such precision though. The water flow and temperature differece in the head would change your efforts, I would think?
Then again, it seems a whole lot of guys seem to think you need to correct small lifter bore variances.