valve to piston checking tool

[Mark Yacavone]

Originally Posted by FireSale

Jim, Mike and whoever:

Since what you're measuring is the distance from the seated valve to the top of the piston, why does it matter what weight spring is holding the valve closed? I know we are talking several hundred pounds of pressure difference between checking and racing springs, but at 0 rpm seated is seated?

Dale

Larry is checking a Super Stock engine, for one thing. Any lift is acceptable .
On a Stocker, you had better check it the way you will run it.
That way, you'll have the maximum lift you can use legally, and at the same time, knowing it will pass tech.

[Ed Wright]

The more rigid your valve train, the less defection, and the less difference between the two springs. I would expect a Stocker engine to see more difference.

[Ed Wright]

Originally Posted by Dragsinger

This is without question a positive checking tool

Larry, do you also have a tool (I think mine came from Moroso, about 20 years ago) that holds a dial indicator, sets on the gasket surface of the head, has an Allen bolt with the Allen head ground to fit in a head bolt hole to locate it. Put the ground bolt head in the short head bolt hole in the head, indicator stem touches the face of the valve head. Measures the distance from the head gasket surface to the face of the valve. I use it to verify my valve hight are all equal. Intake all the same, exhausts all the same. If you used one (you may have) to get that piece of a head there to verify they measure the same as your race heads. Then, that would be an accurate clearance checker.
After that, I measure valve drop to the piston @ TDC on all valves. I have caught piston valve pockets off over .010". I'm kinda anal about all my clearances. I can't afford to be knocking heads off valves. Hell, I can't really afford to be doing this anyway. I need to quit. Getting too old.

[Dragsinger]

Ed, knocking heads of valves is VERY expensive Doing so has set me back a full season.

And yes, I will verify the checking head dimensions are the same as race head. Gary Hettler is doing a replacement head for me and also has the "good" head for double checking.

The cut up head is mostly for fun, I will verify the clearances with new race head.

I expect everything to be OK and "maybe" make the D 4 September race at Thunder Road.

One thing about the cut up head, it is a good conversation piece. At the shop a number of folks have noticed it and looked it over. The same comment from everyone, "I did not realize how the water passages look"

[Dwight Southerland]

Originally Posted by Ed Wright

Larry, do you also have a tool (I think mine came from Moroso, about 20 years ago) that holds a dial indicator, sets on the gasket surface of the head, has an Allen bolt with the Allen head ground to fit in a head bolt hole to locate it. Put the ground bolt head in the short head bolt hole in the head, indicator stem touches the face of the valve head. Measures the distance from the head gasket surface to the face of the valve. I use it to verify my valve hight are all equal. Intake all the same, exhausts all the same. If you used one (you may have) to get that piece of a head there to verify they measure the same as your race heads. Then, that would be an accurate clearance checker.
After that, I measure valve drop to the piston @ TDC on all valves. I have caught piston valve pockets off over .010". I'm kinda anal about all my clearances. I can't afford to be knocking heads off valves. Hell, I can't really afford to be doing this anyway. I need to quit. Getting too old.

X2 I have one of those, too.

[west coast]

Yes it is all about how much deflection your combo has. From what type of rockers you have is a huge in deflection shaft, pedestals or studs. also the length, diameter and wall thickness of the push rods it all adds up. so pushing your cam lift to your max spec and not going over is hard to do when ordering cams. My tear down last year when we measured it was really legal enough to think we were doing something wrong when we measures it.

[Paul Merolla]

I have a question somewhat related to this thread...how do you accurately measure lift at the retainer with beehive springs? (retainer is too small to land the dial indicator on). I was told NHRA sticks a razor blade between the spring and retainer, but I tried that and the razor blade isn't rigid enough to be accurate.

[west coast]

Yes with a razor blade I use the thicker ones like a box cutting knife. My beehive and small retainers are hard to do not a lot of retainer.

[Dwight Southerland]

Originally Posted by Paul Merolla

I have a question somewhat related to this thread...how do you accurately measure lift at the retainer with beehive springs? (retainer is too small to land the dial indicator on). I was told NHRA sticks a razor blade between the spring and retainer, but I tried that and the razor blade isn't rigid enough to be accurate.

Single edge blade.

[FED 387]

Larry -- pls check your emails --Dick