pumping engine for displacement verification

[bob]

so what is the procedure for pumping an engine for displacement verification . I run a diesel , no spark plugs , the injectors are pressed into the head , and secured with a hold down clamp ,not threaded . the injectors are aimed at the piston top center at about a 17 degree angle . so stroke could be measured with an injector removed . I can fabricate a  hollow piece to fit tightly into the injector bore , and I guess some sort of an attachment to connect a hose to . so who does this , and what can I provide to make it work .  thanks

[Stainless1]

Can you disable your valves? and still run the starter.... Pushrod motor? probably need more info about your motor...

[kiwi belly tank]

The only time size verification is required is if you click the record. If you want to keep running after that at the same meet they will seal your engine so you can keep running & attempt to bump it up. Then when you're done, rip the head off it so they can measure it.
  Sid.

[bob]

yes, pushrod motor , can easily disable valves , and crank over engine with starter . just wondering what the procedure is for this . and  what is used instrument wise to hook it all up . so if the engine pumps ok , and displacement is within specs. does the head still need to be removed in the end.

[ggl205]

Sid, unless record runs have changed since 1998, when I qualified for a return record run, I put it in impound. If my return run was above record speed, the car went back to impound for engine size verification. If it passed, my engine was sealed at that time. Only then could I make additional record passes that would not require additional engine size verification. Has that rule changed?

John

[kiwi belly tank]

I don't know John, maybe somebody else can chime in! Back in the same era we upped one of our own records but still thought it was soft & the engine pumped too close to call so Dan sealed it & we raced on until we were done then pulled the heads for inspection.
  Sid.

[ronnieroadster]

Sid, unless record runs have changed since 1998, when I qualified for a return record run, I put it in impound. If my return run was above record speed, the car went back to impound for engine size verification. If it passed, my engine was sealed at that time. Only then could I make additional record passes that would not require additional engine size verification. Has that rule changed?

John

   Having had the pleasure of qualifying on a record a few times and then backing it up on the return run for the record. When were in impound for the back up qualification inspection we always have the engine sealed so we can continue to run. When we are finished making runs we then return to impound to have the engine measured.  That's how we have been doing it since we began running in 2016 and each year thereafter when we set a few more records 
 So I would say things have changed a lot since 1998.
 Ronnieroadster

[Stan Back]

I'm not sure they've changed that much.

If you've already got the record and want to run more, you've got to have it sealed.  And you've got to have it "ready" to take a seal -- such as drilled heads in pan, manifold and/or head so it can't be changed between runs.

I can only date back to 2001 for our car, but that's how it was.

[MRK]

yes, pushrod motor , can easily disable valves , and crank over engine with starter . just wondering what the procedure is for this . and  what is used instrument wise to hook it all up . so if the engine pumps ok , and displacement is within specs. does the head still need to be removed in the end.

After the record pass or return run as it is also known by, the vehicle returns to impound. First we look at the time slips to ensure that the previous record has been bested. After this we look the car over to make sure it still qualifies for class. If it still qualifies for class then we start talking about engine measurements.
It's at our discretion to allow what we call a "seal and go". What I mean by that is we put a temporary seal on the engine and allow you to go back out and race. You MUST have the engine measured by the end of the event to validate all records set. This is risky because if you blow it up real good and we cannot measure it then the record you may have set is out the window. It's in your best interest to have it measured and sealed when you arrive into impound the first time.
The tools used to establish engine displacement vary by engine design. In the case of a pushrod engine we would use what we call "the pump". It's a calibrated glass tube that attaches to the engine and as the engine is turned over a puck inside the the tube marks the displacement of that particular cylinder. We simply take that measurement and multiply it by the number of cylinders to get the engines total displacement. We also measure the engine temperature and assign a heat factor to the calculation if needed.
If you need more information my contact information is on page 191 of the 2021 rule book or page 208 of the 2020 version.
Mike Kaehny
 

[Stan Back]

. . . and if you're told that something is wrong according to the Rule Book, have them show you printed version so they don't accidentally add (or subtract) from the printed word.

[donpearsall]

How in the world can a glass cylinder with a puck connected by a tube to the engine be remotely accurate? I can lose count naming the losses in such a rickety  arrangement. What happened to actually measuring bore and stroke?

At the BSMST event (AMA rules) measuring bore and stroke is the only way to demonstrate displacement. In some cases that can be done through the spark plug hole but for OVC engines with angled or off center plug holes, you must spend all day taking the head off to be measured. Forget about returning the bike to run again unless you brought your whole shop with you.

Don

[Stainless1]

Don, they don't pump small engines... back in the day you could get a small engine oil measured... have not seen that rig in the MC area for several years....if it was too close to tell... off with it's head... ask how I know... a 750 is larger that 45 inches, one of the car size breaks.... was too close to pass with oil, inspector said pull the head.  If your motor is too close to limit, they will tell you they can't get it and guess what...

[Jack Gifford]

... How in the world can a glass cylinder with a puck connected by a tube to the engine be remotely accurate?...

I can't answer that, but I believe P&G has it figured out. Their "pump" consistently came within one cubic inch on my 381 c.i. tractor puller.

[racergeo]

      My engine pumped 363 c.i.  The bore is 4.165 and the stroke is 3.335 so Dan said try on this red hat. I don't know how close you have to be before the head comes off, but I was good.

[Doc B.]

for OVC engines with angled or off center plug holes, you must spend all day taking the head off to be measured. Forget about returning the bike to run again unless you brought your whole shop with you.

The real reason we run for records early in the morning - so we have time to get the head off before impound closes. I recall it took me about three hours my first time.