Yes but that is why I measure 4 spots on each piston: top, bottom front and back (with the same piston/rod assembly). For top and bottom, I rock the piston, and take max and min heights, and average between those 2 numbers. It takes a while to carefully measure all 8 cylinders this way.I wonder about the piston in each corner method as well....I'm no expert but it seems piston rock in the hole with no rings leaves open large areas for measurement error.
Well I couldn't read any more you all are a little whacked out on how you square deck a block. Our block fixture measures 7" from the main journal bar. You cut the deck using the block fixture. They cost about $7000 dollars from Rottler.
You land a pointer on the deck and then to the 7 inch fixture . add the difference to the 7 inch and zero the DRO This is your deck height Square decking is making both decks exactly the same deck height from one bank to the other using a fixture that holds the block at 45 degrees using the cam tunnel center line. We have some foreign V6 motors that are 60 degrees. My son got Block bars for SB and BB mopar and SB and BB Chevy. he told Dave and I that tonight
When Dave told me about this thread we went to the garage to ask my son. When Dave told him about using the pistons on all 4 corners he about fell off his stool. Square decking is making both decks the same height 45 degree off of the center line of the cam and crank tunnel.
I would like to give precise advise but I don't know machine work like my son. What I can tell you is the little he shows us that we understand is unbelievable. And the tools he has.$$$$$$$. Right now this thread is the joke of the garage. If you don't have the equipment don't give bull **** advise.
To the poster , Take the block to a machine shop. Ask if they have a block fixture and the tooling to install your block for square decking. Tell them to show it to you. If he can't walk out.
This is the a block fixture. Notice no pistons necessary. Just precise tooling that cost a lot of money. That is the correct way. Right Dave?
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Well I couldn't read any more you all are a little whacked out on how you square deck a block. Our block fixture measures 7" from the main journal bar. You cut the deck using the block fixture. They cost about $7000 dollars from Rottler.
You land a pointer on the deck and then to the 7 inch fixture . add the difference to the 7 inch and zero the DRO This is your deck height Square decking is making both decks exactly the same deck height from one bank to the other using a fixture that holds the block at 45 degrees using the cam tunnel center line. We have some foreign V6 motors that are 60 degrees. My son got Block bars for SB and BB mopar and SB and BB Chevy. he told Dave and I that tonight
When Dave told me about this thread we went to the garage to ask my son. When Dave told him about using the pistons on all 4 corners he about fell off his stool. Square decking is making both decks the same height 45 degree off of the center line of the cam and crank tunnel.
I would like to give precise advise but I don't know machine work like my son. What I can tell you is the little he shows us that we understand is unbelievable. And the tools he has.$$$$$$$. Right now this thread is the joke of the garage. If you don't have the equipment don't give bull **** advise.
To the poster , Take the block to a machine shop. Ask if they have a block fixture and the tooling to install your block for square decking. Tell them to show it to you. If he can't walk out.
This is the a block fixture. Notice no pistons necessary. Just precise tooling that cost a lot of money. That is the correct way. Right Dave?
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Thank GOD OMM posted this.
It's not that everyone needs the equipment - but the shop they use SHOULD have it if performance work is a part of their service. In the early 2000's my shop got their Rottler and it was night and day. The shop I now use has one too for the same reason.
The correct fixture allows for the actual distance from the true crank centerline to the deck surface. That is the only way to actually square deck - that's what the "square" part of the description is.
So if your shop doesn't have that, either use one that does, or if you can't ignore the worry and move on. Use the Felpro gasket and you'll be fine. Only MLS gaskets might leak. And that's a might.
Well I couldn't read any more you all are a little whacked out on how you square deck a block. Our block fixture measures 7" from the main journal bar. You cut the deck using the block fixture. They cost about $7000 dollars from Rottler.
You land a pointer on the deck and then to the 7 inch fixture . add the difference to the 7 inch and zero the DRO This is your deck height Square decking is making both decks exactly the same deck height from one bank to the other using a fixture that holds the block at 45 degrees using the cam tunnel center line. We have some foreign V6 motors that are 60 degrees. My son got Block bars for SB and BB mopar and SB and BB Chevy. he told Dave and I that tonight
When Dave told me about this thread we went to the garage to ask my son. When Dave told him about using the pistons on all 4 corners he about fell off his stool. Square decking is making both decks the same height 45 degree off of the center line of the cam and crank tunnel.
I would like to give precise advise but I don't know machine work like my son. What I can tell you is the little he shows us that we understand is unbelievable. And the tools he has.$$$$$$$. Right now this thread is the joke of the garage. If you don't have the equipment don't give bull **** advise.
To the poster , Take the block to a machine shop. Ask if they have a block fixture and the tooling to install your block for square decking. Tell them to show it to you. If he can't walk out.
This is the a block fixture. Notice no pistons necessary. Just precise tooling that cost a lot of money. That is the correct way. Right Dave?
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rusty
you can measure end for end but hard to measure tilt or a twist ie square x and y
(but then that's what rod pins are for
seriously OP
let's say your pistons and rods are NOT blueprinted
and you find your deck heights are off end for end
you can always swap the pistons around (keeping the exhaust valve notches in the correct spots) and maybe get them closer
this can adjust for both deck and crank throws being slightly off
let us know what you find out
Thank GOD OMM posted this.
It's not that everyone needs the equipment - but the shop they use SHOULD have it if performance work is a part of their service. In the early 2000's my shop got their Rottler and it was night and day. The shop I now use has one too for the same reason.
The correct fixture allows for the actual distance from the true crank centerline to the deck surface. That is the only way to actually square deck - that's what the "square" part of the description is.
So if your shop doesn't have that, either use one that does, or if you can't ignore the worry and move on. Use the Felpro gasket and you'll be fine. Only MLS gaskets might leak. And that's a might.
I suspect the machine shop that did mine didn't get it quite right. Compression numbers are within a few pounds on all cylinders but the left bank has average 203 psi and the right bank has 208 psi cranking pressure. The thrust bearing on both my 318 and 408 are always in the worst condition when I change them out yearly. Both motors line bored and zero decked and done in the same shop same machinist...who is no longer employed there.
How many thousandts off does 5 pounds of compression equat to?
I've also never seen 8 cylinders with the same compression numbers.
And, a shitty looking thrust is most likely a converter issue.
One side the pistons sit in the hole average .004 the other side sits in the hole .009 on the 408. The 318 sits .012 and on the other .018. same side is low on both blocks.And how do you KNOW that 5 pounds of compression is off BECAUSE of the deck height? Good GRIEF.
One side the pistons sit in the hole average .004 the other side sits in the hole .009 on the 408. The 318 sits .012 and on the other .018. same side is low on both blocks.
One side the pistons sit in the hole average .004 the other side sits in the hole .009 on the 408. The 318 sits .012 and on the other .018. same side is low on both blocks.
Absolutely not. If it was done right the piston should sit nearly equal depths side to side not counting variances in pin location and rod length. Seems odd that both blocks show the same height variance on the same side. tells me they're not setting it up right or their equipment is off. It will contribute to cranking psi side to side as well. Ya know, I may not be too smart but I sure can lift a lot of heavy stuff and I know how to use a depth dial indicator.Ok, not arguing with you but do you think that's the only variable with cylinder pressure?
Absolutely not. If it was done right the piston should sit nearly equal depths side to side not counting variances in pin location and rod length. Seems odd that both blocks show the same height variance on the same side. tells me they're not setting it up right or their equipment is off. It will contribute to cranking psi side to side as well. Ya know, I may not be too smart but I sure can lift a lot of heavy stuff and I know how to use a depth dial indicator.
Didn't take it at all that way RRR... I just like to quote "I may not be too smart but I sure can lift a lot of heavy stuff"...