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What is the difference between honing and boring the cylinder bore? I assume that honing is just resurfacing where as boring is increasing the size of the bore to the next size up. Is honing done afterwards?

I've been reading my service manual and it says that only a damaged bore needs to be honed. Is the honing process something a machine shop does or that you can do yourself with a 'honing stone' -- sounds like something I'd want a piece of precision equipment doing at a professional machine shop.

Also, when installing aftermarket pistons, since they don't come with rings, are you suposed to get oem rings or aftermarket rings from the same people who made your pistons?

When does one get the crank polished and or balanced and what does it involve. Reading through the service manual, I haven't seen anything about balancing or polishing the crank at all.

Thanks -- just trying to learn up on some of the internals side. I'm going to be watching a build or two and potentially doing one of my own at some time so I'd like to start acquiring some knowledge in this area.

Wayne
 

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Razathorn said:
What is the difference between honing and boring the cylinder bore? I assume that honing is just resurfacing where as boring is increasing the size of the bore to the next size up. Is honing done afterwards?

I've been reading my service manual and it says that only a damaged bore needs to be honed. Is the honing process something a machine shop does or that you can do yourself with a 'honing stone' -- sounds like something I'd want a piece of precision equipment doing at a professional machine shop.

Also, when installing aftermarket pistons, since they don't come with rings, are you suposed to get oem rings or aftermarket rings from the same people who made your pistons?

When does one get the crank polished and or balanced and what does it involve. Reading through the service manual, I haven't seen anything about balancing or polishing the crank at all.

Thanks -- just trying to learn up on some of the internals side. I'm going to be watching a build or two and potentially doing one of my own at some time so I'd like to start acquiring some knowledge in this area.

Wayne
You got the honing and boring down. After a bore the builder should hone it as well.

You can hone a cylinder yourself. They have the kits in a auto parts store. I've only done it on snowmobile engines and other small engines. Others i've had sent out.

As far as the piston without rings. I would think the manufacturer should make rings for their pistons. Every piston i've ever bought came with rings. The rings will need to be gapped before install.
 

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Discussion Starter #3
drhonda said:
You got the honing and boring down. After a bore the builder should hone it as well.

You can hone a cylinder yourself. They have the kits in a auto parts store. I've only done it on snowmobile engines and other small engines. Others i've had sent out.

As far as the piston without rings. I would think the manufacturer should make rings for their pistons. Every piston i've ever bought came with rings. The rings will need to be gapped before install.
Gapped? I know you want to push a ring down in the bore and check the gap there, but how does one change that? Do you grind it till it's in spec or something, or do you just check to make sure it came in spec?
 

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Razathorn said:
Gapped? I know you want to push a ring down in the bore and check the gap there, but how does one change that? Do you grind it till it's in spec or something, or do you just check to make sure it came in spec?
yeah you can either do it by hand or use an electronic ring filer (it's a small grinding wheel)
you take off small amounts of material at a time from one side of the ring till it's in spec., checking it along the way

good thread btw, some of this stuff i want to know too, esp the crank info.
 

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Razathorn said:
Gapped? I know you want to push a ring down in the bore and check the gap there, but how does one change that? Do you grind it till it's in spec or something, or do you just check to make sure it came in spec?
Yea, you can use a file or that fancy ring gapper. lol. If you did it a lot it would be a worth while investment.
 

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Discussion Starter #6
So what about polishing and balancing the crank? :D
 

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Alright you got the bore and hone down. Boring is increasing the size, kind of the "rough" increase. Honing is resurfacing the cylinder walls. I would recommend having a shop do the honing for you. Piston to wall clearance is crucial to a motor's performance and an improper hone can affect it.

Also, most aftermarket pistons come with rings. My Wiseco's did and I believe from most shops JE's are an option.

And rings will come with the recommended end gap specs. A Helms will tell you too. Take the ring and push it about 3/4 in using a piston upside down. Use feeler gauges to determine the end gap. Adjust using a file or piston ring filer, a SMALL amount at a time. Thats it.

Balancing the crank is just as it sounds. I know your thinking "what the fuck, I though our crank was already balanced from the factory". It is and quite well too. But balancing it is taking it to the next level. Say your revving to 9 grand an unbalanced crank can cause some damage. Its just being more precise than OEM manufacturing.

Polishing a crank is called "micropolishing" and is done on the journals of the crankshaft. It removes all imperfections and small scratches that occur over time or from the factory. Be sure to recheck your clearances after this is done.
 

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Discussion Starter #9
NJslvrtypes said:
Alright you got the bore and hone down. Boring is increasing the size, kind of the "rough" increase. Honing is resurfacing the cylinder walls. I would recommend having a shop do the honing for you. Piston to wall clearance is crucial to a motor's performance and an improper hone can affect it.

Also, most aftermarket pistons come with rings. My Wiseco's did and I believe from most shops JE's are an option.

And rings will come with the recommended end gap specs. A Helms will tell you too. Take the ring and push it about 3/4 in using a piston upside down. Use feeler gauges to determine the end gap. Adjust using a file or piston ring filer, a SMALL amount at a time. Thats it.

Balancing the crank is just as it sounds. I know your thinking "what the fuck, I though our crank was already balanced from the factory". It is and quite well too. But balancing it is taking it to the next level. Say your revving to 9 grand an unbalanced crank can cause some damage. Its just being more precise than OEM manufacturing.

Polishing a crank is called "micropolishing" and is done on the journals of the crankshaft. It removes all imperfections and small scratches that occur over time or from the factory. Be sure to recheck your clearances after this is done.
So, I talked to a machine shop today when I went buy with a friend to pick up some heads of his. He said that balancing should be done for the crank and rods -- he showed me some balanced cranks and rods that had holes and some that had heavy metal added.

Are you suposed to balance the crank with the rods on it or balance the rods at a different time. The balancing part is all I'm somewhat confused about now -- do they do the crank alone, or crank + rods?
 

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Razathorn said:
So, I talked to a machine shop today when I went buy with a friend to pick up some heads of his. He said that balancing should be done for the crank and rods -- he showed me some balanced cranks and rods that had holes and some that had heavy metal added.

Are you suposed to balance the crank with the rods on it or balance the rods at a different time. The balancing part is all I'm somewhat confused about now -- do they do the crank alone, or crank + rods?
They are balanced seperately. A crank is balanced much like a wheel using a special machine and adding or removing material where needed.

Most aftermarket rods are well balanced. Rods are balanced using a precise scale and same premise, adding or removing where necessary.
 

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Discussion Starter #12
NJslvrtypes said:
They are balanced seperately. A crank is balanced much like a wheel using a special machine and adding or removing material where needed.

Most aftermarket rods are well balanced. Rods are balanced using a precise scale and same premise, adding or removing where necessary.
Of those folks who build engines, how many would you say re-balance their crank. How many do their rods? Does balancing need to be done after polishing?
 

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I got my rods, pistons, crank, flywheel, pulleys balanced.. but then I want a motor than can pull past 9k all the time..
polishing wont really effect the balance of a crank so before or after doesnt matter, but if you get your crank knife egded aswell then balance it, treat it and polish it..
as far as balancing everything else goes, the find the lightest, piston and rod and make all the rest weigh the same, might only be a few milli grams, but weight is weight and rev's are rev's.. My pressure plate and flywheel got 2 holes drilled in them in different places so they balance..

Like it has been stated before if you polish the crank you will need to plastiguage the bearings to check clearnaces, but most should be fine if you use the standard colours..
 

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Razathorn said:
Of those folks who build engines, how many would you say re-balance their crank. How many do their rods? Does balancing need to be done after polishing?
What non-vtec said. Just balancing you can polish before or after. And of course if you are going to knife edge the crank (like I am) then do the aforementioned. I had a shop double check the crank to make sure it was in specs before putting it back in, and it was well within specs.

As far as building the engine and re-balancing. My opinion, it depends on the mileage. If it hasn't been run long, maybe a few thousand miles. I really dont see it necessary. Now with my stroker kit, and the crank work, rebalancing will be a necessity.
 

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K not to be a dick but as a machinist i thought i should dispell honing and boring for you. True boring is done when increasing displacement size but not the only reason its done boring is also done to make the bore have a true round hole. This is do to the fact pistons are egged shaped and oval the bores slightly over time. So a bored hole when needed is ten times better than a honed cyclinder depending on km's of the engine though, Not really worth on a low km's engine. Also forgot to add the only reason honing is needed is to scratch the surface of the smooth bored cyclinders so that oil can travel up the cyclinders and your engine doesnt seize.

The other thing i was always told that balancing a honda crank is almost unneeded because of there great quality from the factory, i could see an advantage in making the oil journals bigger and a micro polish, for the extreme rpm needs arp rod bolts, better bearings and and knife edging the crank.
 

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kolumbo your partially right...but the crank should be balanced if your changing the weights of the pistons and rods....an unbalanced crank will cause early retirement for the motor...i dont think anyone wants that......and the whole knife edging thing....its mostly for balancing purposes...if your crank needed more weight because of your pistons then why shave it off so it can flow better...besides in 9000 rpm knife edging shouldnt make that big of a difference since the oil is everywhere but the bottom. kolumbo your right about the honing and boring thing....and yes they do make high quality cranks str8 from factory.(i love oem)...but when u mess with the pistons and rods and what not...yea get em all balanced...what non-vtec did was the right thing to do.....give the guy EVERYTHING you have attached to the crank and you shouldnt have a problem

Also for advice....make sure the crank journals are all straight...get a str8 edge and lay it on the crank journals.i know your block probably is new but when ya start eating up the bearings in the middle dont ask why:rolleyes:

HONDA PACT RULES!!:dance:
 

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Thanks guys, this is good to know. :) Just in time for me as I am building my motor.

How much does it typically cost for a machine shop to do the following work:-

* I am going to give them a bottom end with stock crank, girdle, pistons & rods still intact. In addition, I will give them a set of brand new pistons & rods to put in. I want them to do the following work:-
- bore/hone to fit the new pistons
- balance the crank
- balance the flywheel
- install the new pistons and rods with new bearings
- hot tank the block

Any ballpark number would be great.

Choon
 

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uhhh putting it together im not sure...but balancing the crank...i had an estimate...cant remember if its 150 or 250....good luck wif the build man
 

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its ganna be a lot of money thats all i got to say. if you take out the crank and rods/pistons you will be saving ur self some money. you can have them rebuild it for u.

bore and hone is like $40/cylinder = 160
block dip is like 40 unless they hook u up
rebuild can be from $450-$600 depends on who quotes u.
balancing the crank could be around $150-$250
resuface a flywheel is like $20

so ur looking around $1030 or lower.

this is not including tare down on the block.
really if u lack the skill to put it back together than have them do it but atleast you can take it apart its not that hard i think anyone can take anything apart putting it back together is key.

hope this helps and hope i saved u a lil money.

also what motor are u building cuz i know some sites were u can get the bearing cheap i got a complete set for my k24a2 for $168 main and connecting let me know if u need the site.

-jay
 
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