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Old 09-22-2010, 04:37 PM
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zero decking block

Couple of questions about decking a block.

I am going to be zero decking my block...I think. Here are my questions:

Do I need to mock up the engine before getting it decked to do an actual measurement before telling the machine shop how much to remove or is it "close enough" to do a stack up of the parts advertised dimensions and go with that? For instance, stack adds up to 9.001.....just tell them to take it to 9.001.

Can I tell the machine shop to just take the deck to 9 inches or do I have to tell them how much material to remove? (I think deck height is measured from the center of the crank and wasn't sure how they get that measurement if hand them a bare block?)

What is a ball park figure for the cost of decking the block?

I am sure these are easy questions as this is the first time having any machine work done to a block.

Levi

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Old 09-22-2010, 05:53 PM
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Quote:
Originally Posted by 1975yellowC3
Do I need to mock up the engine before getting it decked to do an actual measurement before telling the machine shop how much to remove or is it "close enough" to do a stack up of the parts advertised dimensions and go with that? For instance, stack adds up to 9.001.....just tell them to take it to 9.001.
Hey Levi, my standard answer when dealing with ANYTHING is TRUST NOBODY. I'm reading more and more horror stories as suppliers increasingly use offshore facilities, so TRUST NOBODY.

First, get the pistons you will use. Take the pistons, rods and the block to the machine shop and tell them to bore the block to fit the pistons with whatever piston to wall clearance that's recommended by the piston manufacturer. Have them assemble the pistons to your rods. Pick up the block and pistons/rods from the shop and take them home.

Mount the block on an engine stand. Remove the main caps and clean out all machining debris from the main saddle and from the cylinder bores at cylinder numbers 1, 2, 7 and 8 (the four corners of the block). Place main bearings at the #1 and #4 main bearing positions. Oil the bearings. Place the crankshaft into position and snug down the main bearing caps on these two positions. You do not need to torque them, just snug them down. Now, we have the crank in place and are able to rotate it. I don't use #5 position because it is harder to get the bearing into and out of position. #1 and #4 will work just fine.

Choose any one piston/rod assembly. We are going to use only ONE to do the measuring at all four corners of the block, therefore eliminating any variances between all of the piston/rod assemblies. Note very carefully that there is a large fillet side and a small fillet side on the big end of the rod. The large fillet must be placed on the side of the rod journal that is next to the counterweight. Placing the small fillet side of the rod against the corner of the fillet at the counterweight can result in interference, even though we are going to use only one rod on the journal in this exercise.

This may sound confusing to you, but you will get the idea as you go along. On #1 cylinder, for instance, the large fillet of the rod will be facing forward. On #2 cylinder, for instance, the large fillet of the rod will be facing rearward. Don't worry about whether the piston is facing forward or backward. It will not matter.

Turn the block on the engine stand so that the #1 cylinder is straight up and down and the block deck is flat and level.
Remove the rod cap. Install bearing halves in the rod and cap and oil them. Install plastic protective covers on the rod bolts to prevent nicking the crank journal as you install the piston in the bore. Turn the crank so that the #1 rod journal is at the bottom of its stroke. Install the piston (less rings). Snug the rod cap. You don't need to torque the cap, just snug it up.

You will need a good steel rule or straightedge and a set of feeler gauges. As you stand at the side of the block, you are going to span the rule across the cylinder bore at either the 3:00 O'Clock or 9:00 O'Clock positions of the piston and about 1/4" from the edge of the bore. If you try to measure at the 12:00 O'Clock or 6:00 O'Clock positions, the piston can tilt back and forth on its wrist pin and give you erroneous measurements.

Stand the rule on its edge and bring the piston up to what you perceive to be TDC. Insert different feeler gauge blades between the piston crown and the bottom of the rule until you get a snug fit. Have a buddy there with you so he can move the crank through the top dead center position of the piston back and forth (bringing the piston down in the bore maybe a 1/4" and back to TDC each way clockwise and counterclockwise of the crank while you hold the rule and blade in position to make sure you have nailed the measurement). You will need to hold the rule down pretty good to make sure the piston isn't pushing it up. The narrowest measurement you can record will be the piston deck height for that cylinder. De-grease the block deck there and record the measurement on the deck right next to the cylinder with a black, indelible Sharpie felt tip pen.

Remove the rod nuts and remove the piston/rod assembly. Re-install the plastic boots and move on to cylinder #7 to repeat the procedure. Then turn the block on the stand so that cylinders #2 and #8 are straight up with the block deck flat and repeat the procedure.

When you are through, you will know the piston deck height of each cylinder exactly. Don't be surprised to find that the decks are sloped one way or the other and that you have different measurements from one end of the block to the other. It is commonplace to miss clearing away a chip in the machine at the factory from the previous operation, so that everything the machine operator does after that will be skewed. That's what we're trying to correct here. You can return the block to the machine shop to be decked with the confidence that any further machine work will be accomplished from a good base of information. TRUST NOBODY.

By the way, this is a good chance for you to do some teaching to your buddies. I doubt that any of them have ever done this exercise, so it would be a good learning experience and add to your credibility at the same time. Invite a crowd. Tell them the cost of the education is to bring a six-pack.

One last thought. When you get the short block all assembled, you might want to check all 8 pistons again with the rule and feeler gauge at the 3:00 O'Clock and 9:00 O'Clock positions on each piston. A difference in the dimension from one side of the piston to the other could indicate a bent rod. It could also, of course, mean that the piston isn't machined square, but the pistons are usually pretty close.

Quote:
Originally Posted by 1975yellowC3
What is a ball park figure for the cost of decking the block?
Depends on the shop. $100 to $200. Whatever it costs, it's worth it. Make sure the shop is using quality equipment and registers the block off the main saddle to do the decking.

Last edited by techinspector1; 09-22-2010 at 06:22 PM.
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Old 09-22-2010, 05:55 PM
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You need to assemble a crank in block and measure four corners with piston/rod/bore combination you are using. This the minimum requirement and only way you are going to get a true zero deck.

If block is decked to a spec like 9.001. Your piston and rod stack may not be true. Everything has + - specs and can add up.

Sorry, TechInspector we were both typing at same time. Just a shorter version BOB
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Old 09-22-2010, 06:02 PM
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Quote:
Originally Posted by BOBCRMAN@aol.com
You need to assemble a crank in block and measure four corners with piston/rod/bore combination you are using. This the minimum requirement and only way you are going to get a true zero deck.

If block is decked to a spec like 9.001. Your piston and rod stack may not be true. Everything has + - specs and can add up.

Sorry, TechInspector we were both typing at same time. Just a shorter version BOB
It's all good Bob. I trust what you have to say in all respects and look forward to reading your replies.
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Old 09-22-2010, 07:03 PM
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Quote:
By the way, this is a good chance for you to do some teaching to your buddies. I doubt that any of them have ever done this exercise, so it would be a good learning experience and add to your credibility at the same time. Invite a crowd. Tell them the cost of the education is to bring a six-pack.
Tech never mind the six pack, great stuff,,,were do I deliver the 24 pack? This is another example from a "senior" member as to why this forum rules, that info is priceless to someone like myself who has never done it and I hope others appreciate just reading it as much as I do, I don't want to brown nose but man O man I just had to add a thanks.
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Old 09-22-2010, 07:21 PM
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TI,
Thanks for the very thorough post. As a side note, I am pretty sure I am going to use the pistons you had suggested to me for my motor. I am hoping to not have to bore the motor, but I don't have it back out of he car yet so haven't done any measuring. The "boss" has given me a cease work order on the car until my son's 2nd bday party is over! We are having it in the garage I was told no major overhauls til then.....fair enough.

Bob...thanks for your post as well. I am new and appreciate anyone who's willing to help.

It is nice to have all you guys on here for a newbie like me to soak up all this knowledge.
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Old 09-22-2010, 07:21 PM
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Quote:
Originally Posted by techinspector1
Hey Levi, my standard answer when dealing with ANYTHING is TRUST NOBODY. I'm reading more and more horror stories as suppliers increasingly use offshore facilities, so TRUST NOBODY.

First, get the pistons you will use. Take the pistons, rods and the block to the machine shop and tell them to bore the block to fit the pistons with whatever piston to wall clearance that's recommended by the piston manufacturer. Have them assemble the pistons to your rods. Pick up the block and pistons/rods from the shop and take them home.

Mount the block on an engine stand. Remove the main caps and clean out all machining debris from the main saddle and from the cylinder bores at cylinder numbers 1, 2, 7 and 8 (the four corners of the block). Place main bearings at the #1 and #4 main bearing positions. Oil the bearings. Place the crankshaft into position and snug down the main bearing caps on these two positions. You do not need to torque them, just snug them down. Now, we have the crank in place and are able to rotate it. I don't use #5 position because it is harder to get the bearing into and out of position. #1 and #4 will work just fine.

Choose any one piston/rod assembly. We are going to use only ONE to do the measuring at all four corners of the block, therefore eliminating any variances between all of the piston/rod assemblies. Note very carefully that there is a large fillet side and a small fillet side on the big end of the rod. The large fillet must be placed on the side of the rod journal that is next to the counterweight. Placing the small fillet side of the rod against the corner of the fillet at the counterweight can result in interference, even though we are going to use only one rod on the journal in this exercise.

This may sound confusing to you, but you will get the idea as you go along. On #1 cylinder, for instance, the large fillet of the rod will be facing forward. On #2 cylinder, for instance, the large fillet of the rod will be facing rearward. Don't worry about whether the piston is facing forward or backward. It will not matter.

Turn the block on the engine stand so that the #1 cylinder is straight up and down and the block deck is flat and level.
Remove the rod cap. Install bearing halves in the rod and cap and oil them. Install plastic protective covers on the rod bolts to prevent nicking the crank journal as you install the piston in the bore. Turn the crank so that the #1 rod journal is at the bottom of its stroke. Install the piston (less rings). Snug the rod cap. You don't need to torque the cap, just snug it up.

You will need a good steel rule or straightedge and a set of feeler gauges. As you stand at the side of the block, you are going to span the rule across the cylinder bore at either the 3:00 O'Clock or 9:00 O'Clock positions of the piston and about 1/4" from the edge of the bore. If you try to measure at the 12:00 O'Clock or 6:00 O'Clock positions, the piston can tilt back and forth on its wrist pin and give you erroneous measurements.

Stand the rule on its edge and bring the piston up to what you perceive to be TDC. Insert different feeler gauge blades between the piston crown and the bottom of the rule until you get a snug fit. Have a buddy there with you so he can move the crank through the top dead center position of the piston back and forth (bringing the piston down in the bore maybe a 1/4" and back to TDC each way clockwise and counterclockwise of the crank while you hold the rule and blade in position to make sure you have nailed the measurement). You will need to hold the rule down pretty good to make sure the piston isn't pushing it up. The narrowest measurement you can record will be the piston deck height for that cylinder. De-grease the block deck there and record the measurement on the deck right next to the cylinder with a black, indelible Sharpie felt tip pen.

Remove the rod nuts and remove the piston/rod assembly. Re-install the plastic boots and move on to cylinder #7 to repeat the procedure. Then turn the block on the stand so that cylinders #2 and #8 are straight up with the block deck flat and repeat the procedure.

When you are through, you will know the piston deck height of each cylinder exactly. Don't be surprised to find that the decks are sloped one way or the other and that you have different measurements from one end of the block to the other. It is commonplace to miss clearing away a chip in the machine at the factory from the previous operation, so that everything the machine operator does after that will be skewed. That's what we're trying to correct here. You can return the block to the machine shop to be decked with the confidence that any further machine work will be accomplished from a good base of information. TRUST NOBODY.

By the way, this is a good chance for you to do some teaching to your buddies. I doubt that any of them have ever done this exercise, so it would be a good learning experience and add to your credibility at the same time. Invite a crowd. Tell them the cost of the education is to bring a six-pack.

One last thought. When you get the short block all assembled, you might want to check all 8 pistons again with the rule and feeler gauge at the 3:00 O'Clock and 9:00 O'Clock positions on each piston. A difference in the dimension from one side of the piston to the other could indicate a bent rod. It could also, of course, mean that the piston isn't machined square, but the pistons are usually pretty close.


Depends on the shop. $100 to $200. Whatever it costs, it's worth it. Make sure the shop is using quality equipment and registers the block off the main saddle to do the decking.
So your decking to where the pistons on each corner come up to the deck?? and not off the main line!!!

We have been blue printing alot of blocks over the years and if a engine builder of machine asks for a 9.000 deck that is what we supply them and if your using good equipment and a good rotating assembley you should not have to fit up a rotator to get zero. So far we have had zero problems.

On our own engines we build we always seem to be with in .0015 when we are done.

If I had to fit every rotator to try to get zero deck I would have close the doors a long time ago

Again use a quality machine shop that has the proper equipmant to do the job right and use quality parts.

I deal with shops all over the U.S. and I can tell you this not one I deal with have to fit up a ratator in a block to get the correct deck height. HMMMMM
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Old 09-22-2010, 08:29 PM
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In the real world. We are talking an engine that is being built by a novice on a budget with non "professional" race type parts. Using local shops..

I've been decking blocks since the late sixties mostly on older equipment that most "average" or better shops use..Some shops even claiming and advertising to be top quality "race" shops.

In these shops the best job results are usually done by the four corner method.
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Old 09-22-2010, 08:54 PM
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Quote:
Originally Posted by CNC BLOCKS NE
So your decking to where the pistons on each corner come up to the deck?? and not off the main line!!!
Aaaaaw Geez, now I have to defend my position.

I should know by now that as soon as I begin an in-depth explanation to a person on this board concerning measurements or procedures for machining, that I'm going to get grief from one or more of you high and mighty machine shop types. There is more than one way to skin a cat and I don't know why you have to come off like your feathers have been ruffled, using exclamation points along with your attitude. No, not off the main bearing bore because the OP or someone reading this in Bolivia may not have access to a 12" dial caliper with ball anvil or other precision measuring equipment, but they are pretty likely to have a steel rule and a feeler gauge set. Total tool cost, maybe 10 bucks if they didn't have those items in the first place.

But that wasn't the intent of the post in the first place. The OP was clueless and I'm sure there are others reading this thread who are equally clueless as to how all this works. So, what was I supposed to tell the OP? Take everything to the machine shop and trust them? How does that help anyone to learn anything? Although I have laid it out as best I can, I'm not forcing anyone to carry through with this procedure. They can still drop everything off at the shop and hope for the best.

I'm not altogether unfamiliar with what you do and how you do it. My father was a tool and die maker who taught me how to read a vernier micrometer almost before I could ride a bike and I spent quite a lot of time with him in the shop on weekends up until I was grown and left home. Since then, I have been a frequent visitor to automotive machine shops.

The only variable in using the procedure I outlined is the centerline of the rod journals in relation to the centerline of the crank (how far is the throw out of blueprint?). Otherwise, it is a perfectly reliable way of determining the block deck height with commonly available tools. In the whole scope of things, the throws may be off a little, the rod length may be off a little center to center and the compression height of the pistons may not be smack on the money one piston to the other. But normally, these things will cancel each other out on a street or street/strip build. If you are building a race motor, of course you will be blueprinting each component and would have no use for a steel rule and feeler gauge.

Quote:
Originally Posted by CNC BLOCKS NE
We have been blue printing alot of blocks over the years and if a engine builder of machine asks for a 9.000 deck that is what we supply them and if your using good equipment and a good rotating assembley you should not have to fit up a rotator to get zero. So far we have had zero problems.
On our own engines we build we always seem to be with in .0015 when we are done. If I had to fit every rotator to try to get zero deck I would have to close the doors a long time ago.
I'm very pleased that all is going well for you. Nobody is asking you to fit up a rotator. The info I posted is for the OP and the guy in Bolivia.

Quote:
Originally Posted by CNC BLOCKS NE
Again use a quality machine shop that has the proper equipmant to do the job right and use quality parts.
This statement has nothing to do with teaching someone how to do this at home with simple tools. You keep forgetting about the poor guy in Bolivia.

Quote:
Originally Posted by CNC BLOCKS NE
I deal with shops all over the U.S. and I can tell you this not one I deal with have to fit up a ratator in a block to get the correct deck height. HMMMMM
And again, nobody says you or anyone else has to,... well, maybe except for the poor guy in Bolivia.
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Old 09-22-2010, 09:34 PM
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gauging deck

All good advice.and should always be done but.
An upper end performance machine shop has a deck gauge and will hit it inside .001.. our guy charges 90 for decking to your specs and 40 extra to gauge it.I think he has excellent prices partly because he has a newer "smart machine". It's not a kwik way; I think it's Swedish.

The other guy we use to go to before he retired had a machine jig which had to be set up through the cam and main bores. Once one deck was gauged and cut, the jig would automatically stop to index at 90deg, while maintaining it's elevation.
He's told us many times over the years, something like one corner took .026 and another as low as .020 while the mid deck might have been +.004".
When I first started having decking done I was amazed at how far out the factory small block could be.

That's why I started a factory crank indexing question thread. I used the archaic term "journal timing", sorry. I'm curious as to how many people experienced a "good" factory crank having a journal as much as a half degree out.

Just like a factory set of rods can vary 9 or even ten grams from light to heavy. Since I discovered that we've always balanced our rods pistons, and send out the crank with our #s.

Last edited by Duntov; 09-22-2010 at 09:37 PM. Reason: typo
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Old 09-22-2010, 10:00 PM
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Quote:
Originally Posted by 1975yellowC3
Couple of questions about decking a block.

I am going to be zero decking my block...I think. Here are my questions:

Do I need to mock up the engine before getting it decked to do an actual measurement before telling the machine shop how much to remove or is it "close enough" to do a stack up of the parts advertised dimensions and go with that? For instance, stack adds up to 9.001.....just tell them to take it to 9.001.

Can I tell the machine shop to just take the deck to 9 inches or do I have to tell them how much material to remove? (I think deck height is measured from the center of the crank and wasn't sure how they get that measurement if hand them a bare block?)

What is a ball park figure for the cost of decking the block?

I am sure these are easy questions as this is the first time having any machine work done to a block.

Levi
CNC is telling you right.
If you want zero deck, let your machinist do the math for you, any competent machinist will measure the stroke, rod length and pin height and determine what the deck needs to be. if you use techs method and you use the shortest of piston and rod combo you have, you probably end up with a block you can't use. doesn't matter if your equip. is top of the line or not. you measure everything then deck.
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Old 09-22-2010, 10:27 PM
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Old way still works...

Quote:
Originally Posted by techinspector1
Aaaaaw Geez, now I have to defend my position.

I should know by now that as soon as I begin an in-depth explanation to a person on this board concerning measurements or procedures for machining, that I'm going to get grief.........
I figure it should be assumed that a guy who takes the time to gauge his block in the way described, has also taken time to blue print his rods/piston rod combo to exact length, before he even weighed them. A Tech type builder knows that rod/piston combos are subject to vary in stack height and addresses that before he starts the balance process. Otherwise he might have 3 or 4 pounds variation in compression between cylinders which might have been prevented. Same guy also CCs the chambers and all that goes with it. that method of gauging was done probably a hundred years before CNC or otherwise intelligent machines.

Don't get me wrong; I like a shop with intelligent machines and machinist to match; But that doesn't make the old way wrong or significantly less accurate.

Always blueprint, always balance....otherwise why bother?
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Old 09-22-2010, 10:31 PM
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Quote:
Originally Posted by ho-bo woods
CNC is telling you right.
If you want zero deck, let your machinist do the math for you, any competent machinist will measure the stroke, rod length and pin height and determine what the deck needs to be. if you use techs method and you use the shortest of piston and rod combo you have, you probably end up with a block you can't use. doesn't matter if your equip. is top of the line or not. you measure everything then deck.
Translation>>>"If you don't know your motors know your machinist" LOL
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Old 09-22-2010, 10:43 PM
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Quote:
Originally Posted by techinspector1
Hey Levi, my standard answer when dealing with ANYTHING is TRUST NOBODY. I'm reading more and more horror stories as suppliers increasingly use offshore facilities, so TRUST NOBODY.

First, get the pistons you will use. Take the pistons, rods and the block to the machine shop and tell them to bore the block to fit the pistons with whatever piston to wall clearance that's recommended by the piston manufacturer. Have them assemble the pistons to your rods. Pick up the block and pistons/rods from the shop and take them home.

Mount the block on an engine stand. Remove the main caps and clean out all machining debris from the main saddle and from the cylinder bores at cylinder numbers 1, 2, 7 and 8 (the four corners of the block). Place main bearings at the #1 and #4 main bearing positions. Oil the bearings. Place the crankshaft into position and snug down the main bearing caps on these two positions. You do not need to torque them, just snug them down. Now, we have the crank in place and are able to rotate it. I don't use #5 position because it is harder to get the bearing into and out of position. #1 and #4 will work just fine.

Choose any one piston/rod assembly. We are going to use only ONE to do the measuring at all four corners of the block, therefore eliminating any variances between all of the piston/rod assemblies. Note very carefully that there is a large fillet side and a small fillet side on the big end of the rod. The large fillet must be placed on the side of the rod journal that is next to the counterweight. Placing the small fillet side of the rod against the corner of the fillet at the counterweight can result in interference, even though we are going to use only one rod on the journal in this exercise.

This may sound confusing to you, but you will get the idea as you go along. On #1 cylinder, for instance, the large fillet of the rod will be facing forward. On #2 cylinder, for instance, the large fillet of the rod will be facing rearward. Don't worry about whether the piston is facing forward or backward. It will not matter.

Turn the block on the engine stand so that the #1 cylinder is straight up and down and the block deck is flat and level.
Remove the rod cap. Install bearing halves in the rod and cap and oil them. Install plastic protective covers on the rod bolts to prevent nicking the crank journal as you install the piston in the bore. Turn the crank so that the #1 rod journal is at the bottom of its stroke. Install the piston (less rings). Snug the rod cap. You don't need to torque the cap, just snug it up.

You will need a good steel rule or straightedge and a set of feeler gauges. As you stand at the side of the block, you are going to span the rule across the cylinder bore at either the 3:00 O'Clock or 9:00 O'Clock positions of the piston and about 1/4" from the edge of the bore. If you try to measure at the 12:00 O'Clock or 6:00 O'Clock positions, the piston can tilt back and forth on its wrist pin and give you erroneous measurements.

Stand the rule on its edge and bring the piston up to what you perceive to be TDC. Insert different feeler gauge blades between the piston crown and the bottom of the rule until you get a snug fit. Have a buddy there with you so he can move the crank through the top dead center position of the piston back and forth (bringing the piston down in the bore maybe a 1/4" and back to TDC each way clockwise and counterclockwise of the crank while you hold the rule and blade in position to make sure you have nailed the measurement). You will need to hold the rule down pretty good to make sure the piston isn't pushing it up. The narrowest measurement you can record will be the piston deck height for that cylinder. De-grease the block deck there and record the measurement on the deck right next to the cylinder with a black, indelible Sharpie felt tip pen.

Remove the rod nuts and remove the piston/rod assembly. Re-install the plastic boots and move on to cylinder #7 to repeat the procedure. Then turn the block on the stand so that cylinders #2 and #8 are straight up with the block deck flat and repeat the procedure.

When you are through, you will know the piston deck height of each cylinder exactly. Don't be surprised to find that the decks are sloped one way or the other and that you have different measurements from one end of the block to the other. It is commonplace to miss clearing away a chip in the machine at the factory from the previous operation, so that everything the machine operator does after that will be skewed. That's what we're trying to correct here. You can return the block to the machine shop to be decked with the confidence that any further machine work will be accomplished from a good base of information. TRUST NOBODY.

By the way, this is a good chance for you to do some teaching to your buddies. I doubt that any of them have ever done this exercise, so it would be a good learning experience and add to your credibility at the same time. Invite a crowd. Tell them the cost of the education is to bring a six-pack.

One last thought. When you get the short block all assembled, you might want to check all 8 pistons again with the rule and feeler gauge at the 3:00 O'Clock and 9:00 O'Clock positions on each piston. A difference in the dimension from one side of the piston to the other could indicate a bent rod. It could also, of course, mean that the piston isn't machined square, but the pistons are usually pretty close.


Depends on the shop. $100 to $200. Whatever it costs, it's worth it. Make sure the shop is using quality equipment and registers the block off the main saddle to do the decking.
If you go back and reread your advise its pretty lame as you should never bore any block off an unsquared deck thats just plain common sence.

I can surly tell by this avise you have never machined a block before and any quality shop out there does not have to fit everything to deck a block, If you dealing with a shop that needs to this your better off finding a better shop.

When decking a block the main line should be addressed first with a line hone as everything is measured off the mains, And when decking you should be using a squaring fixture which comes off the cam and crank center lines to get you 45 degrees and you decks will be 90 degrees apart. Then you bore the block off the squared decks THATS HOW ITS DONE
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Old 09-22-2010, 10:49 PM
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Originally Posted by ho-bo woods
CNC is telling you right.
If you want zero deck, let your machinist do the math for you, any competent machinist will measure the stroke, rod length and pin height and determine what the deck needs to be. if you use techs method and you use the shortest of piston and rod combo you have, you probably end up with a block you can't use. doesn't matter if your equip. is top of the line or not. you measure everything then deck.
I can see some one is using there head here!! Very good advice.


I can't beleive these guys telling this guy to bore his block first HMMMM
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