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> Cylinder boring, Sizes?
Black22
post Dec 13 2011, 06:28 PM
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I heard people here say that boring out your 94mm cylinders is probably a better bet than buying new, possibly sub-par due to metals used, cylinders. What about the 93mm cylinders? Would the cylinder walls be too thin? Am I wrong in assuming all cylinders are cast the same thickness and then bored out to specific sizes before distribution?

I have a 1.8 that I'm taking to a 1911. I was going to wait until the motor gave out. Well it still runs strong and is very peppy, but I just spun a rod bearing and she's knocking pretty bad after a decent drive. (IMG:style_emoticons/default/barf.gif) Already have a new crank ands pistons, just need to know if I have the Mahle 93mm stock cylinders, should I bore them out or buy new 96mm AA cylinders?
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jcd914
post Dec 13 2011, 07:19 PM
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1.8 cylinder should be fine to bore out for the 96's.
1.8 and 2.0 cylinders have the same outside dimensions.
1.7's are smaller where they fit the cylinder heads.
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Jake Raby
post Dec 13 2011, 09:10 PM
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Boring cylinders requires a torque plate to mimic the loads that the cylinder is under with a head bolted on and torqued up.. You must also know the exact roughness average and plateau finish that the rings are designed to work with. Skirt clearance is also critical to proper (quiet) operation and break in.

Don't think that you can achieve satisfactory results working with someone that has never bored these cylinders before- not happening.

This post has been edited by Jake Raby: Dec 13 2011, 09:10 PM
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r_towle
post Dec 13 2011, 09:39 PM
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QUOTE(Black22 @ Dec 13 2011, 07:28 PM) *

I heard people here say that boring out your 94mm cylinders is probably a better bet than buying new, possibly sub-par due to metals used, cylinders. What about the 93mm cylinders? Would the cylinder walls be too thin? Am I wrong in assuming all cylinders are cast the same thickness and then bored out to specific sizes before distribution?

I have a 1.8 that I'm taking to a 1911. I was going to wait until the motor gave out. Well it still runs strong and is very peppy, but I just spun a rod bearing and she's knocking pretty bad after a decent drive. (IMG:style_emoticons/default/barf.gif) Already have a new crank ands pistons, just need to know if I have the Mahle 93mm stock cylinders, should I bore them out or buy new 96mm AA cylinders?

you can bore the 1.8 ones out.
I believe Rimco, near you, does this and has for a few years.

Rich
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Jake Raby
post Dec 13 2011, 09:49 PM
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Rimco did a good job with this before Todd left... Now I wouldn't send them a Briggs and Stratton to machine
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Cap'n Krusty
post Dec 14 2011, 10:43 AM
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Whatever you do, be sure to buy the correct pistons for your crank/rod combination!

The Cap'n
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Black22
post Dec 14 2011, 11:14 AM
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QUOTE(Cap'n Krusty @ Dec 14 2011, 08:43 AM) *

Whatever you do, be sure to buy the correct pistons for your crank/rod combination!

The Cap'n


Will do Cap'n. Everything is stock except the piston size. Pistons are 96mm for stock 66mm crank size. Crank is a 10/10 polished 66mm. I can't buy bearings until I have the case checked. (IMG:style_emoticons/default/mad.gif)

I still need to measure pistons to compare what Mark Henry's dimensions are.

I just needed to know what the census was about boring 93mm vs. new cylinders.
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76-914
post Dec 14 2011, 08:53 PM
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QUOTE(Jake Raby @ Dec 13 2011, 07:49 PM) *

Rimco did a good job with this before Todd left... Now I wouldn't send them a Briggs and Stratton to machine

(IMG:style_emoticons/default/agree.gif) Word!
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Black22
post Dec 14 2011, 08:58 PM
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QUOTE(76-914 @ Dec 14 2011, 06:53 PM) *

QUOTE(Jake Raby @ Dec 13 2011, 07:49 PM) *

Rimco did a good job with this before Todd left... Now I wouldn't send them a Briggs and Stratton to machine

(IMG:style_emoticons/default/agree.gif) Word!


(IMG:style_emoticons/default/av-943.gif) I just pictured you saying that with your Texas accent and it cracked me up!
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Jake Raby
post Dec 14 2011, 10:13 PM
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QUOTE(Black22 @ Dec 14 2011, 07:58 PM) *

QUOTE(76-914 @ Dec 14 2011, 06:53 PM) *

QUOTE(Jake Raby @ Dec 13 2011, 07:49 PM) *

Rimco did a good job with this before Todd left... Now I wouldn't send them a Briggs and Stratton to machine

(IMG:style_emoticons/default/agree.gif) Word!


(IMG:style_emoticons/default/av-943.gif) I just pictured you saying that with your Texas accent and it cracked me up!


Georgia accent perhaps? I ain't from Texas, boy!
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Black22
post Dec 14 2011, 11:14 PM
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QUOTE(Jake Raby @ Dec 14 2011, 08:13 PM) *

QUOTE(Black22 @ Dec 14 2011, 07:58 PM) *

QUOTE(76-914 @ Dec 14 2011, 06:53 PM) *

QUOTE(Jake Raby @ Dec 13 2011, 07:49 PM) *

Rimco did a good job with this before Todd left... Now I wouldn't send them a Briggs and Stratton to machine

(IMG:style_emoticons/default/agree.gif) Word!


(IMG:style_emoticons/default/av-943.gif) I just pictured you saying that with your Texas accent and it cracked me up!


Georgia accent perhaps? I ain't from Texas, boy!


Sorry Jake! I meant the "Word" comment from 76-914!
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