Bore Tech JE pistons in Maney sleeve alloy?

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Re: Immediate request on Maney sleeve alloy?

hobot said:
I really like the idea of .0045 at top and .006" at bottom of ring travel. Now how do I attain that?
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I have a sunnen hone I would use, but I don't have a mandrel that size. Yet. They go for $300-$600 used on ebay.

When things aren't going good with the hone the problem is bell or barrel shape. You use a diamond dressing file by hand to dress the hump or dip out of the stone to keep it cutting a straight hole. In your case you would dress the stone to enhance the taper honing more at one end. Probably use a short stone to help flare out the end. Will take fancy footwork with footpedal that applies pressure to stone to finish taper.

Too much info in this post to quote. I think your on the right track. Pick your numbers and roll the dice.
 
Bore Tech on Maney sleeve alloy?

Bore Tech on Maney sleeve alloy

"why didn't I have problems with it?"
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Yeah man Dancec's this sort of stress/decisions beats the snot out divorces, bankruptcy and expiring friends and family and pets. Peel & me is more similar to your youthful exuberance going against engine wisdom grain. No way can I heat stress Peel in my surrounds for 100 miles, just scoot up ~150 in 10th to 1/4 mile opens now and then and parking lot stunts while learning to handle it on & off road while ruining rear tires fast as i can. Then the real heat testing on to use up a pair of JSM pistons on Texas Mile drag strip for basic pecking order and engine tolerance tests then on to Peel's main point showing how mis guided corner crippled balloon tire buzz bombs are when any leaning on power involved.

If I had Peel's junk here I've an oven to heat Maney barrel with head on and JE Pistons up to 600'F and check bores and piston dia. Past Peel had Gunkote on barrel but now has Swain's Black Body Emission coat over entire blackened engine. A new set of pistons and new sleeves would be a rather low replacement expense compared to the total loss on project spent. Ken's got his hands full of good + tough things so a bit of time to contact jE Pistons and Steve Maney for their sense of swelling risk taking to report here. Peel's CR ratio's via online calculators imply 7.5 to 17:1 range to tolerate. Peel was so easy inviting to ride beyond the normal I'm wanting to let others like you have their way with her to share the hi before we die. With a handle of Edgefinder and depth of bore dressing you deserve a thrill to wow me watching your road orgasms on her too.
 
Re: Immediate request on Maney sleeve alloy?

hobot said:
Whoa WZ that some brain swelling stuff to take in. Peel's bore's could get into 600'F+ for a time. Your data implies over 6000th's possible, ugh. I've not time enough to post the rules of thumb on bossted applications and special fuel but adding a couple to 3+ 1000th's is usually recommend, more so on bigger bores. On the other hand Peel has piston, chamber, valves and ports ceramic insulated coated which they claim to reduce clearance needs not to mention the carbide Bore Tech.
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Just a reminder, Steve. Your JS Engineering JE pistons are not coated. You're thinking of the original Maney 920 pistons that you were going to use before you decided to go with Jim's long rod/light piston kit. If you want the current pistons coated, we'd have to send them off to Swain.

Ken
 
Bore Tech on Maney sleeve alloy?

Oh oh Ken caught another my senile delayers in time. Yes crowns should get insulated like chambers and sides the friction coat. Ideally the crowns should be mirror polished to reflect the IR photons that get through the coating on top plus cryogenic tempering which should be done first of all. Sorry but better send them to me to handle pistons and the heavy duty cam chain too as I am sold on cryo on other chains stable link life. Shipping costs more than the cryo. Will attempt heat pow wow on cylinders and piston makers but so far your .005" top clearance with some widening below is still the game plan. I don't feel as brave an experimenter as Dancer.
 
Re: Immediate request on Maney sleeve alloy?

Here's California rider Frank Foster's down and dirty thermal binding resolution in his BSA B50.

Not precision, just backyard.
Seizures show in cylinder in the area of the base gasket, so I just threw the lot in the kitchen oven and heated it all to 350F. Still seized.
Reduced temp to 250F, then free at upper end of the stroke, but tight below.
Started removing material with 'precision' hone below ring travel until piston would travel full stroke.
Threw it all together and it works.
POS design. I have a vast collection of pistons seized on the skirt, and cylinders scored at bottom of piston travel. Go figure.
Fresh bore @ piston skirt diameter + .0035"
Lotsa experience running noisy @ .006-.008" clearance.......
 
Re: Bore Tech on Maney sleeve alloy?

hobot said:
I don't feel as brave an experimenter as Dancer.
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Dancer gave many reasons why his worked and possibly one reason very near the top of the list would be the 0.0045" piston fit. I don't know but suspect his piston was cast, which would put his fit nearly as loose as cast pistons ever get fit. If in fact his piston was cast, your 0.005" with the forged piston would be tight by comparison.

Here's a bit more of the calculated data on how temperature affects piston/bore clearance. The data table provided yesterday served a purpose but was very limited in scope. I prefer a graph to present quantitative information, as it is easier to visualize (at least for me) much larger data sets, thereby expanding the scope of the discussion/understanding. All the parameters used here are as described above for the data table.

Bore Tech JE pistons in Maney sleeve alloy?


The graphed data should describe reasonably well how your system responds to temperature change when equilibrated. Unfortunately your system is in a perpetual state of flux and never equilibrates, thus the graphical data does little to describe the temperature gradient existing from top to bottom of both the cylinder and the piston.

I still like your idea of heat soaking the cylinder and piston at elevated temp and then measuring their fit (even though it's an equilibrium measurement). If you're still thinking that somewhere around 0.005" is the clearance you'll build with, then I'd check at 350F, as this is near the point where interference should occur. It's also a low enough temp that you won't alter the piston or cylinder heat treatment. I personally wouldn't heat them any higher than that.

So, you couldn't sell yourself a 0.007" fit clearance with APC taking up the slack? :wink:
 
Re: Bore Tech on Maney sleeve alloy?

WZ507 said:
Dancer gave many reasons why his worked and possibly one reason very near the top of the list would be the 0.0045" piston fit. I don't know but suspect his piston was cast, which would put his fit nearly as loose as cast pistons ever get fit. If in fact his piston was cast, your 0.005" with the forged piston would be tight by comparison.
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That engine build was a more or less a "run what you brung approach" to engine building. It started stock but I would have no part in that so I replaced the cam, and pistons and went with Dunstal Decible mufflers so when that was not enough I had to try the Drouin.

I was hoping someone would chime in and state what the high compression Omega pistons were made of (cast of forged). My guess is they were cast but someone might know about those pistons of that era. Anybody?
 
Re: Bore Tech on Maney sleeve alloy?

WZ this is serious last-life time dream machine chance to pull off so am delighted with your scope on the scale of temps per clearance changes. i can't use them yet as I don't know Peel's temp range in the parts concerned - but BY Golly after what I've done and seen in Norton heat tolerance and welders and online heat tempering of Al etc I've no concern to hit 600'F to flash off oil before welding or remove fused in races so if that low of temp would hurt Peel's tempers then Peel will blow up regardless before I got her to the sports bike spanking range. I figure Peel must burn 3x's a Combat's 50 hp of fuel heat 127,00 btu's/hr which implies Peel must flow and sustain 150 hp 381,664/hr. Calc's imply 8000 rpm with drag cam, 10.5 CR, 10 PSI and octane for full ignition pressure Peel could approach that, *IF* long stroke bore friction speeds don't win first. Snail blower's pressure curve goes up exponentially if loaded and Drouin crude impeller ain't topped out choking at 8K rpm, ie: 56K blades as Drouin PSI graphs shows plus Bruce McGregor has seen 15 PSI on his stock 850 * so 10 PSI is conservative but to plug in even a bit more PSI in calculators gives nutzo results to report. HEAT flow dumping and BORE/RING speed friction will limit Peel's power but don't know which first yet. Please continue on the .007" clearance reasoning as my first impressions before Ken's and Frank's and Dancer's inputs was .0065" all the way down. Kenny Cummings engine views comnoz showed us of his Maney barrel JSM piston combo had crowns beaten over and bores ovaled till no mo race power. Cummings is a gentlemen till in the saddle he gets Godiza throttle handed, which i admire. Hm maybe Jay Leno would know something?

http://convert-to.com/conversion/power/ ... er-hr.html
 
Re: Bore Tech on Maney sleeve alloy?

Dances with Shrapnel said:
WZ507 said:
Dancer gave many reasons why his worked and possibly one reason very near the top of the list would be the 0.0045" piston fit. I don't know but suspect his piston was cast, which would put his fit nearly as loose as cast pistons ever get fit. If in fact his piston was cast, your 0.005" with the forged piston would be tight by comparison.
Click to expand...

That engine build was a more or less a "run what you brung approach" to engine building. It started stock but I would have no part in that so I replaced the cam, and pistons and went with Dunstal Decible mufflers so when that was not enough I had to try the Drouin.

I was hoping someone would chime in and state what the high compression Omega pistons were made of (cast of forged). My guess is they were cast but someone might know about those pistons of that era. Anybody?
Click to expand...

The Omega pistons in the factory short stroke were cast.

Ken
 
Re: Bore Tech on Maney sleeve alloy?

JSM's JE pistons in Peel are forged so more expansion prone than cast. Here's a quote from this short and sweet thermal characterization on piston in bore factors.
(/) Piston Taper.
To compensate for the unequal expansion due to maximum temperature
at crown and minimum at the bottom of the skirt, the piston is tapered along its axis, the crown
end having the smallest diameter (Fig. 3.82C). The degree of taper varies along the piston length,
greatest being in the ring-belt. The clearances between the piston skirt and the cylinder wall is
about 0.05% and 0.10% respectively at the bottom and top of the skirt.
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http://what-when-how.com/automobile/piston-automobile/

This are getting beyond my need to know but others might make sense of its detailed piston alloy and type review.
http://www.alueurope.eu/wp-content/uplo ... istons.pdf
http://automotiveenginesgroup3.blogspot ... iston.html

Hm this shows a way to configure oil pockets in skirts so piston friction decreases with speed.
http://www.federalmogul.com/en-US/Media ... cript2.pdf

PDF]
Numerical investigations of piston cooling using oil jet in ...
http://www.researchgate.net -
Control of piston temperatures by cooling of these pistons has become one of ... Isotherms of the predicted temperature profiles in a production grade piston ...
 
Re: Bore Tech on Maney sleeve alloy?

illustrates the result of measurements of a distorted cylinder bore. The radial scale has been greatly distorted to illustrate the details. Expands most at top, duh.
Bore Tech JE pistons in Maney sleeve alloy?

https://www.dieselnet.com/tech/lube_cons_ring.php


Ain't just temperature that expands top of bore more than lower.
http://www.precisionenginetech.com/tech ... on-part-1/
Bore Tech JE pistons in Maney sleeve alloy?

Bore Tech JE pistons in Maney sleeve alloy?

This graph illustrates how cylinder concentricity can be affected by head clamping, operation with regard to temperature and operation with regard to wall temperature and gas pressure. - See more at: http://www.precisionenginetech.com/tech ... j7f1V.dpuf

My 'puter can't yet read this one. [PPT] The Role of Cylinder Geometry on Thermo-mechanical ...
web.iitd.ac.in › ...‎
By custom, engines that have a bore/stroke ratio of between 0.95 and 1.04 ... Later it was realized that in an actual engine pressure and temperature profile data ...
 
Re: Bore Tech on Maney sleeve alloy?

JE Piston tech http://www.jepistons.com/AboutUs.aspx 714 894-6650, said they could give piston swelling data if they had the batch number off pistons but that in air cooled alloy cylinder with cast iron sleeve on low boost applications to set bore clearance between .002 -.004", ugh.
 
Re: Immediate request on Maney sleeve alloy?

lcrken said:
jseng1 said:
You're taking a risk at .005" Especially with a blower etc. The feed back I've been getting says they are tight enough.

See a 750cc JE piston below that was run at .004" (this is not one of my lightweight pistons). Another thou ain't gonna do it. You are pushing the extremes with a blower and anything can (and usually does) happen.

Don't underestimate how much a forged pistons needs to expand or how much a Norton overheats with its inadequate fins.
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I wouldn't disagree with that, Jim. Bore-Tech seems to think that you can use a bit tighter clearance with their coating, so Steve has settled on .005" at top of cylinder, with taper to .006" at bottom. I guess we'll see how it works out.

Ken
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OK
I'm interested to know how tight my pistons can run. As long as its not my suggestion.
 
JSM, if ya have batch numbers JE could give us an expansion/temp chart. I'll be creeping up on Peel's heat fit performance and will look in very often after each step up in heat so will report back with photo's to judge if ok to jump to next level of heat boost and rpm. Calculations and RBRacing imply about 15% water mass per fuel mass will give enough octane/detonation tolerance to run full pressure ign. adv. up to 17:1 CR but could add more plain water or windshield fluid w/o power loss to cool crown-chamber more. I don't think I can pull off what I want if Peel can't break under 10 sec 1/4 mile or top out near 170.
 
I bought 2 new .020 over piston kit for my 18 hp Kohler boxer mower engine for $370 and had Bore Tech fit them and coat bores for $360 to send back this week. Left Coast Racing did Peel's bigger bottom taper hone so Bore Tech treatment will cost ~$285. Hope to live long enough to get some pay back eh. My ole mower gets used at party gatherings like the mechanical bull rides at western discos so its nick name is 'The Buffalo" as makes a dull task kind of off roading fun. I hope Peel'$ nick name is 'Bulletproof'.
 
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