straightlinespeed
Sometimes I pretend to be normal
Anyone ever use a Piston Stop tool? If so how did you like using it and what brand did you purchase?
Piston Stop Advice
- Thread starter straightlinespeed
- Start date
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grimreaper
Cross Member
I made mine years ago from an old spark plug. Simple but effective.
straightlinespeed
Sometimes I pretend to be normal
Im looking at them and Ive seen how they are made, but Im confused on how you know how to set the depth of the stop?
67Dart273
Well-Known Member
First of all what engine is this for?
Depth is not all that critical. You are not trying to stop the engine at TDC, but rather "at some point" as the piston comes up. As the piston comes up, to, and over TDC, it slows down, so "down some" is more accurate than "right at the top."
What you do is, bump the piston on the stop in normal direction, then go around all the way and bump in the opposite direction. You mark the balancer with temporary marks at each "stop" and this creates two marks --which are equidistant from TDC.
Biggest single thing (and something some commercial ones are not good) is that the stop much be rigid and not move
I made mine for a SB and have had it since the SEVENTIES!!!
This commercial one which is adjustable does not seem to have a jam nut to lock the stem, an example of one that might not stay in one place. If you could add a lock nut it would probably be OK:
Depth is not all that critical. You are not trying to stop the engine at TDC, but rather "at some point" as the piston comes up. As the piston comes up, to, and over TDC, it slows down, so "down some" is more accurate than "right at the top."
What you do is, bump the piston on the stop in normal direction, then go around all the way and bump in the opposite direction. You mark the balancer with temporary marks at each "stop" and this creates two marks --which are equidistant from TDC.
Biggest single thing (and something some commercial ones are not good) is that the stop much be rigid and not move
I made mine for a SB and have had it since the SEVENTIES!!!
This commercial one which is adjustable does not seem to have a jam nut to lock the stem, an example of one that might not stay in one place. If you could add a lock nut it would probably be OK:
straightlinespeed
Sometimes I pretend to be normal
Ok, I was just curious since all of them I've seen have adjustable stops. It makes sense to me that your just trying to get a equal distance.
For a LA 360 with magnum heads. They look very simple to make I like that yours threads in and has a smooth stem instead of the threaded end touching the piston.
straightlinespeed
Sometimes I pretend to be normal
Now if Im going to use timing tape, I assume once I find true TDC I install the tape with the zero mark right on the TDC mark?
DaveBonds
Garage Trash
Yes.
Just know that the Mopar Performance tape works, but it's set up for the timing mark on the pass side, rather than driver side.
It works on your engine, but the numbers may show upsideown. They should gain from 0 - 90 going clockwise on the tape, so as the timing light shows the balancer advancing, the numbers on the tape can pass 0. The 0 on the tape should be on your corrected mark.
You may also want to put a line on your balancer that is visible when you hit it with a timing light, that extends from the inner hub to the ring that goes outside of the rubber isolator, to see if it flexes or changes during acceleration or increase static RPM measurements (checked at 1000, 2000, 3000 etc.)
If it flexes make note of how much with multiple marks on the outer ring to calculate against your timing tape, or get a new balancer.
Just know that the Mopar Performance tape works, but it's set up for the timing mark on the pass side, rather than driver side.
It works on your engine, but the numbers may show upsideown. They should gain from 0 - 90 going clockwise on the tape, so as the timing light shows the balancer advancing, the numbers on the tape can pass 0. The 0 on the tape should be on your corrected mark.
You may also want to put a line on your balancer that is visible when you hit it with a timing light, that extends from the inner hub to the ring that goes outside of the rubber isolator, to see if it flexes or changes during acceleration or increase static RPM measurements (checked at 1000, 2000, 3000 etc.)
If it flexes make note of how much with multiple marks on the outer ring to calculate against your timing tape, or get a new balancer.
I will add to what Dave Bonds said, make sure that its the correct tape for your balancer...some balancers I believe are different sizes, which will make a difference.
67Dart273
Well-Known Member
I prefer not to use tape. Just measure carefully around your balancer with a light flexible tape, ACCURATELY, and figure how many "degrees per inch." Then figure how many inches for say, 40*. Mark that off with your tape, carefully, and double check your measurements.
Then you can use dividers to mark that in half for 20*, and with the dividers duplicate the 40 and 20 dimension and mark out to 60* for vacuum advance. Then divide the 20* marks in half to 10, and if you want, to 5*. Use a small square and a scribe. Doesn't take all that long.
Crackback doesn't even do that -- just uses a hunk of masking tape and makes a temp mark to get timing set.
Then you can use dividers to mark that in half for 20*, and with the dividers duplicate the 40 and 20 dimension and mark out to 60* for vacuum advance. Then divide the 20* marks in half to 10, and if you want, to 5*. Use a small square and a scribe. Doesn't take all that long.
Crackback doesn't even do that -- just uses a hunk of masking tape and makes a temp mark to get timing set.
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