Cylinder honing

[modok]

Indeed all the honing machine does is.....save arm work, and contain the mess.
All of the magic is in the hone head itself, and stroking it correctly....although that's no simple matter.

[Jaredb1]

Jared,
Something is murky to me here.
I am assuming you are working on a 360.
You stated you had a block bored and honed to 4.030.
It was too noisy to suit you so you tore it down.
You measured that you had .008 PTW clearance. Sounds reasonable for a lot of race pistons.
You said the pistons call for .0045-.0055.
Where is that spec coming from which still sounds loose for a street engine?

Here is where it gets murky.
If it was bored to 4.030 and the pistons were made for that bore things should work out just fine.
Too noisy for a muffled car perhaps but acceptable.
Were the pistons made incorrectly or badly collapsed after being run for a while?

I get the idea you want to blame the machine shop.
Don't be too hasty in this regard
Granted your measurements of out of round and taper are not wonderful but you didn't say how many miles you put on it.

Guess I am just saying the numbers don't add up as they should.
I think your problem is more likely an incorrect piston choice for quiet street use.

Chevy wins the 500

And oh hell yeah, honing .010 7 more times is sadistic.
.002-.005 is bad enough but your arms will be amazing.

Dave,
Thanks for taking the time to help me out. I got the required clearances from Mahle catalog. The pistons in question are Mahle 28cc inverted dome for small block Chrysler. 2618 material. You are 100% correct in saying they probably wasn't the best choice for quiet street engine.I could have lived with it if not for the excessive oil consumption.
As far as the pistons go, they currently measure 4.0235. This is measuring .625 up from the bottom of the skirt per the Mahle catalog. The coating is wore thin in this area. Almost to the point it is transparent. An odd thing is the coating is worn off the first 1/8 of the skirt and just below the oil ring. I would think the gauge point would wear the most since it is the largest diameter of the piston. Any thoughts on that?
The measurements on the piston seem a little undersized to me, but then again I don't know how much the coating affects that. If skirt collapse was the issue, would they all measurethe same?
I had 6-7 thousand miles on it before I tore it down. Definitely enough time to have some wear. Honestly the original honing marks are all visible throughout the cylinders. I have no way of knowing how much anything has worn. The bore measurements were all over the place. Anywhere from 4.0295 to 4.0315. The results weren't much different when I measured the bottom below the ring travel. Or above the ring travel. That's how I got .008 clearance numbers. I had 2 cylinders at that number. Not all. Same thing with taper. The cylinder I have honed out already measured 4.030 at the top and 4.0315 at the bottom below ring travel. So the numbers I gave was the extremes. They all were different. The only thing they had in common was the .0005 out of round. Ultimately the blame lays with me for not checking everything before assembly. Had I measured everything like I should have we would have a better understanding of what went wrong.

[modok]

mahle pistons have the original skirt size stamped on top of the piston.
I have not ever found one that was wrong.
So, if they have collapsed it will be easy to determine.

Although, I'm not sure if they keep that tradition with the "motorsport" pistons.

Do they?

[enginenut2]

Considering the problem -inacceptable oil consumption- I think the cylinder conditions would not be a problem with conventional modern rings. I'm sure you have considered other paths for the oil to be inducted, and besides valve guides, and crankcase ventilation needs, there is the thing with the small block Chrysler having the intake manifold with a sheet metal plate covering the bottom of the manifold in the lifter chamber. I think the mid-late 90's with throttle body. The gasket would shrink and leak into the inlet tract and the oil consumption could be tremendous. Just thinking.

[HDBD]

Not a fan of the lisle tool. It is similar to the Sunnen AN manual hones. For reasons of cross hatch control, not sizing I would get it to a shop that has a modern Sunnen or Rottler power stroker and does the job right. By hand you may be able to get the sizing right but not the crosshatch and that will be a major contributor to ring seal, ring life, and oil control.

[Dave Koehler]

HDBD,
Did you read the whole thread?

[HDBD]

Yes and agree there are likely some other issues that you and others eluded to. All needs to be looked at or even with proper sizing the motor will go back together and still not work properly.

[Dave Koehler]

Yes and agree there are likely some other issues that you and others eluded to. All needs to be looked at or even with proper sizing the motor will go back together and still not work properly.

Cool.
I don't want to do any more hand honing either.
I just get tight when cylinder honing machines are considered to be infallible.

[ClassAct]

Yes and agree there are likely some other issues that you and others eluded to. All needs to be looked at or even with proper sizing the motor will go back together and still not work properly.

Cool.
I don't want to do any more hand honing either.
I just get tight when cylinder honing machines are considered to be infallible.

LOL. The machines aren't infallible for sure. It's just a tool. But as you well know, the tool using the tool is most likely the lesser tool to begin with. If that makes sense.

Wasn't is Yunick who said some guys could break a bowling ball in a sand box with no tools or some such thing? That is a fact. The machine can't fix stupid.

[Jaredb1]

Thanks everyone for your help. My pistons don't have any markings other than the part number etched in the top, and another row of numbers and letters that have no meaning to me.
The first thing I checked when I realized I was using oil was the PCV valve. I tried it with, without, and just a breather in each valve cover. No change in oil consumption.
The intake was the next suspect. The air gap intake for magnum engines doesn't use the metal valley tray. It uses two intake gaskets and end rail gaskets. When I took it apart I didn't see any evidence of the gaskets leaking. I didn't see any evidence of oil or residue in the intake ports of the heads. When I reassembled I decided not to use the cork end seals, just in case they were holding the intake up and keeping it from getting a good seal. I just used a bead of silicone on the ends. Oil consumption did not change.
I should have done a leak down test before tearing it down. I do know that upon tear down I noticed the pistons had a lot of coked oil between the top and second rings. The accumulator groove is packed full of it for about half the circumference of the pistons. Does that tell us anything? Looking at the face of the tapered piston rings, the face is shiny about half way across the face in some areas, and wore all the way across the face in other areas. Does that mean anything?

[Newold1]

I see and hear this type of situation a lot now days. It's the case of a little knowledge and a little to little shop expertise is a dangerous thing!!

In a case such as this I think now days unless the shop is really expert in both machining equipment , engine block machining knowledge and commitment to holding correct, exacting tolerances the finished work is usually off the mark.

This is definitely a case where for the money alone you have spent you could have gone to Mopar performance and purchased a nice high performance crate engine that would give you a nice truck to drive and play with. This did not appear from your descriptions to be a race engine so even the use of 2618 forged pistons was even necessary or required and a nice set of 4032 pistons with their tighter clearances would probably have not given you any noisey cold piston slap and possible oiling issues.

I guess what I am trying to say nicely is that if you are not really heavily experienced in machining performance short blocks and all the really necessary machining, fixtures, equipment and procedures -DON'T GO THERE!

I know there are so many performance engine enthusiasts out there who want to DIY, but it's way more difficult than many think and they read so much DIY stuff they think they can easily do it themselves and end up with a great result. My guess is that more than 30- 50% of these cases end up with substandard results, a poor performance result and engines with all sorts of bugs and necessary fixes which end up costing so much more in money and time than they ever imagined! It really takes quite a few years of hands on experience, expertise and really good procedures and equipment to have 90% or better outcomes. If you are only going to try it one -3 times in your performance building world your odds of a great outcome are under assault. JMHO

[ClassAct]

I see and hear this type of situation a lot now days. It's the case of a little knowledge and a little to little shop expertise is a dangerous thing!!

In a case such as this I think now days unless the shop is really expert in both machining equipment , engine block machining knowledge and commitment to holding correct, exacting tolerances the finished work is usually off the mark.

This is definitely a case where for the money alone you have spent you could have gone to Mopar performance and purchased a nice high performance crate engine that would give you a nice truck to drive and play with. This did not appear from your descriptions to be a race engine so even the use of 2618 forged pistons was even necessary or required and a nice set of 4032 pistons with their tighter clearances would probably have not given you any noisey cold piston slap and possible oiling issues.

I guess what I am trying to say nicely is that if you are not really heavily experienced in machining performance short blocks and all the really necessary machining, fixtures, equipment and procedures -DON'T GO THERE!

I know there are so many performance engine enthusiasts out there who want to DIY, but it's way more difficult than many think and they read so much DIY stuff they think they can easily do it themselves and end up with a great result. My guess is that more than 30- 50% of these cases end up with substandard results, a poor performance result and engines with all sorts of bugs and necessary fixes which end up costing so much more in money and time than they ever imagined! It really takes quite a few years of hands on experience, expertise and really good procedures and equipment to have 90% or better outcomes. If you are only going to try it one -3 times in your performance building world your odds of a great outcome are under assault. JMHO

I've never seen an OOTB MP crate engine is run. Valve jobs are crap at best, the honing is questionable, I've seen clearances all over the map and other things.

[jed]

As I have said befor DONT listen to the nay Sayers. I know 3 shops in the DFW area that use older Van Norman and
Kwik Way boring bars and hone with the Sunnen hand hone very similar to your Lyle.
A short story.
2 of the shops occasionally dyno engines. The dyno shop is old and respected for circle and drag race engines.
During one dyno session the shop owner who does the dyno work had made 2 pulls on the engine and it was almost completely sealed up. He wanted to know they how they Honed there cylinders. The shop owner has a CK10 and a CV616 and got schooled by a couple of guys with a hand hone.

[jake197000]

correct me if im wrong but you cant measure true bore geometry with a bore gauge.its all most of us have and if done right works just fine.

[Dave Koehler]

correct me if im wrong but you cant measure true bore geometry with a bore gauge.its all most of us have and if done right works just fine.

Correct me if I'm wrong but I don't think anyone brought up the term "straightness".