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-   -   Finding an engines displacement (https://www.racingjunk.com/forums/showthread.php?t=22380)

GLADIATORINC 11-29-2008 07:16 AM

Finding an engines displacement
 
Is there a way to find out an engines displacement if you know nothing of the engine with out tearing it apart and physically measuring bore and stroke?? I swear I saw at the race track someone use a graduated tube that hooks up to the sparkplug hole and when the engine is cranked it measure the volume of air?? pumped??

lanham 11-29-2008 02:14 PM

That is what you call "pumping your block".The only place i know of using that is truck pulling to keep the trucks within the rules.I am pretty sure you have to take the rocker arms off of the cylinder that you are checking and pull the plugs.So yes they do make a device to check cid and is supposed to be accurate within a certain percentage.

GLADIATORINC 11-29-2008 06:15 PM

Do you know what this device is called?

zipper06 11-29-2008 08:21 PM

It's called P&Ging, almost all rounde round tracks have the tester, because of limited rules in each class on compitation. In thew old days at AHRA,NHRA,IHRA that's how they used to check after a win or if protested. I can't remember how many times i got P&G'ed when running a blown/b/gasser.
Here's what the tester looks like, and if you know someone who is a tech at a sprint car track he may can test your engine for you. You have to disable the valves/remove puhrods on the cylinder being tested and remove all spark plugs. They normally roll the dice to see which cylinder will be tested, that being because a lot of the guys in the old days use to build an engine with one side bored bigger than the other.

They are not cheap, but here's the website to when they sell them

Zip.
http://www.precisionmeasure.com/test1.htm

dparker 11-29-2008 08:31 PM

These are still used at alot of dirt tracks. You might call a local track operater and see if they will let you use their tester.

GLADIATORINC 11-30-2008 06:10 AM

They are pricey!! It's cheaper to take the heads off!!!LOL

Thanks for your help.


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