Piston Ring Gap

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perry kete
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First Name: Dennis
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* REQUIRED* Type and Year of Model Ts owned: 1922 Coupe 1927 Touring
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Piston Ring Gap

Post by perry kete » Mon Jun 20, 2022 8:21 am

I have looked at the search function and didn't find exactly what I am looking for so I thought I would ask here.

I have had my engine bored to 20 thousands over and I have purchased new aluminum pistons and rings also 20 thousands over.

I have a piston clearance of 2-1/2 to 3 thousands when inserted in the cylinder.

I now need to check ring gap and would like to know what the ring gaps should be.

Thanks
1922 Coupe & 1927 Touring


TXGOAT2
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Re: Piston Ring Gap

Post by TXGOAT2 » Mon Jun 20, 2022 8:24 am

You need to get information on both piston to cylinder clearance and ring end gap. Both are very important.


speedytinc
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Re: Piston Ring Gap

Post by speedytinc » Mon Jun 20, 2022 8:34 am

perry kete wrote:
Mon Jun 20, 2022 8:21 am
I have looked at the search function and didn't find exactly what I am looking for so I thought I would ask here.

I have had my engine bored to 20 thousands over and I have purchased new aluminum pistons and rings also 20 thousands over.

I have a piston clearance of 2-1/2 to 3 thousands when inserted in the cylinder.

I now need to check ring gap and would like to know what the ring gaps should be.

Thanks
Your piston clearance is too tight by 1/2. Should be .004 -.006. I go with the higher end. ,005-,006.
By memory - .018". Go with the ring mfg's recommendation.


tmodeldriver
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Re: Piston Ring Gap

Post by tmodeldriver » Mon Jun 20, 2022 11:00 am

Good rule of thumb for ring gaps is .003" per inch of bore diameter. A little too much is better than not enough. On a T Model engine I'd shoot for about .012". Bob

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Topic author
perry kete
Posts: 1629
Joined: Sun Jan 06, 2019 11:46 am
First Name: Dennis
Last Name: Seth
* REQUIRED* Type and Year of Model Ts owned: 1922 Coupe 1927 Touring
Location: Jefferson Ohio

Re: Piston Ring Gap

Post by perry kete » Tue Jun 21, 2022 4:12 pm

John,

Thanks for the information on the pistion clearance. I went down and rechecked each cylinder at the top and bottom and I can place a .005 feeler guage next to the cylinder at both the top and bottom. I don't know why I didn't keep advancing the feeler guage size when I first measured it but for some reason I stopped when I hit .003.


Bob,

Thanks for the information about the ring gap I will check that next.

Denny
1922 Coupe & 1927 Touring

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