Cylinder Walls

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And all these years I thought they were chrome moly rings! More then one reference to chrome moly rings Always came in a black box. Must have been something I picked up under the hood with few bears and a few guys, " yea its got chrome moly rings and a 3/4 race cam!"
 
No such thing as chrome-moly piston rings......... Either chrome, or molybdenum, but you can't have them both together.
 
69 Cuda 440 said:
Piston Knurling

A Micrometer is the only way to go when measuring a round or circular object.
Click to expand...

You trust a dial indicator to measure gear backlash,, the probe moves a precision rack, which turns a precision gear, and moves a precision needle,, you trust it to measure 4 - 8 thousands of an inch.(distance),, You trust a dial indicator probe to move a precision rack, to turn a precision gear , that moves a precision needle to indicate when a lifter is at .050 lift, - not .049, - not .051, but precisely .050..(distance), - as a foundation for your cam set-up.. You trust a dial indicator yada yada to measure .002 transmission freeplay ..(distance)

Yet you put the same dial indicator,, it's presicion needle, precision gear, on a similar precision rack, that's 4 - 5 inches long,, call it a vernier caliper,, and you deem it's not accurate enuff to compare a .005 diff on 2 different shaft diameters..(distance)..

If you believe this, Give your head a shake,, cuz your logic and common sense,, need a reboot.. imho

Matching pistons to bores, rods to journals,, working in 10 thousands of an inch, - I use a mic,, searching thru my shim collection,, or going to a pipe shop,, caliper is close enuff, cuz I'm not taking a mic to a pipe shop unless I'm searching for precision..

hope it helps
 
inertia said:
You trust a dial indicator to measure gear backlash,, the probe moves a precision rack, which turns a precision gear, and moves a precision needle,, you trust it to measure 4 - 8 thousands of an inch.(distance),, You trust a dial indicator probe to move a precision rack, to turn a precision gear , that moves a precision needle to indicate when a lifter is at .050 lift, - not .049, - not .051, but precisely .050..(distance), - as a foundation for your cam set-up.. You trust a dial indicator yada yada to measure .002 transmission freeplay ..(distance)

Yet you put the same dial indicator,, it's presicion needle, precision gear, on a similar precision rack, that's 4 - 5 inches long,, call it a vernier caliper,, and you deem it's not accurate enuff to compare a .005 diff on 2 different shaft diameters..(distance)..

If you believe this, Give your head a shake,, cuz your logic and common sense,, need a reboot.. imho

Matching pistons to bores, rods to journals,, working in 10 thousands of an inch, - I use a mic,, searching thru my shim collection,, or going to a pipe shop,, caliper is close enuff, cuz I'm not taking a mic to a pipe shop unless I'm searching for precision..

hope it helps
Click to expand...

Well Then,

I guess I'll just have to throw out my 'Browne and Sharpe' Micrometer Set.

Those Bastards never told me I could use a Dial-Caliper to measure
Piston's and Cylinder Bore Holes.

$2000 'Down-the-Drain'
 
69 Cuda 440 said:
Well Then,

I guess I'll just have to throw out my 'Browne and Sharpe' Micrometer Set.

Those Bastards never told me I could use a Dial-Caliper to measure
Piston's and Cylinder Bore Holes.

$2000 'Down-the-Drain'
Click to expand...

I think you missed the last paragraph, and perhaps the whole point.

The knurling is still approx .005 proud..

hope it helps.
 
Caliper Nailed It,, .006 proud.. imagine that,, know your tools capabilities and limitations..

oh, almost forgot ---....,,,, //// .. lol
 

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I really didn't want to get involved in this, but, I just can't help it.
--IMHO the hole in post#1 looks pretty sad. The top inch, the most important inch, on my screen, looks aweful. It looks like the last guy did exactly like what you are now contemplating. His exercise didn't make 2000 miles. How is that anyone could think a similar do-over would get any different results?
--Every time the ring goes through that rut, the compression will go straight into the pan.And when it does it will burn the oil up and fill the crankcase with that mess. The PCV won't keep up for long, and even if it does,those gasses will just pass out the tailpipe in a constant billow. New rings might ease the burden for a few miles but the rut will win.It will eat the corners off those brand new rings in record time.
Keep in mind that a .001 change in bore size up there is a .0031416 change in ring gap. So if the rut is 2 or 3 thou deep that could be a 6 to 10 thou change in gap. Now the ring is moving in and out of the ringland,as it's getting smacked by the rut, and exactly when it's under max pressure. That poor ring is working hard. Then you add a bit of carb issues;and take away some oil film.... Now it's like you're whipping the slave Israelites who are making bricks without straw.No wonder Moses couldn't stand it.
--So anyway, having worked on small engines for many years, I occasionally had a customer who actually wanted me to do similar work on his engine. After my appeal fell on deaf ears, I slammed it together and reminded him that there would be no warranty. Well, you can imagine the rest.I think I only did that a few times, cuz I remember packing up a few engines, that I refused to patch this way. Course we are talking one and two and three cylinders for the most part, so one would think that the cost of boring and pistons would not be that great, right? Not so, this world is run on different mark-ups. One piston-kit, and one bore, can easily run to $110/150Can.So I can see the customer's point. But hey, this Quad, or this Boat-motor, or this Dirtbike, or this Sled, or Whatever is a non-essential transportation item. It's a toy or a pleasure vehicle. So if you could afford to purchase it, you already got way more disposable income than I do. Grin and bear it, or park it; I don't feel sorry for them anymore.
--Getting back to the OP;
How much is your time worth? What time period does 2000miles represent. If you slam it together as is and it makes another 2000 miles, it will be worth just about nothing when it comes out later.So if you spend just $200Usd on it, and 2days, and divide that by 2000, you will get a number that represents dollars per mile. But if you do it right, and it theoretically can go 100,000miles, and you sell it later for just what the pistons and boring costs, then your cost per mile will be exactly the same, but the benefit per mile will be far greater, and most especially to the next guy who anticipates 98,000 more miles.
--I know what I'd do.
Keep in mind I'm basing my decision on just what I can see on my screen.
Whatever you decide,all the best to you.
 
inertia said:
Caliper Nailed It,, .006 proud.. imagine that,, know your tools capabilities and limitations..

oh, almost forgot ---....,,,, //// .. lol
Click to expand...

Now, you're starting to look more like a Machinist with the Micrometer, than
a Garage Mechanic with the Calipers.

Don't ever make that mistake again.
 
69 Cuda 440 said:
Now, you're starting to look more like a Machinist with the Micrometer, than
a Garage Mechanic with the Calipers.

Don't ever make that mistake again.
Click to expand...

ROFL... thank-you,, thank-you very much.. lol

I believe you've just witnessed the reason for my nickname.

It takes a lot to get me going , but once I'm rolling,, I am driven till completion, whatever it is..

cheers to all.. I am done.. lol . where's my recliner.. ??
 
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