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Discussion Starter #1
Hello all,
I'm getting ready to do the big bore thing on my TC88.
The pistons and rings are from NRHS, CP forged flat tops, and Total Seal rings.
The top ring has no markings whatsoever so it can go in either way.
The second ring has a chamfer on one inside edge. All of the cross section drawings I've seen always have the chamfer on the top. However, I was reading the tech advice at NRHS website and it stated the chamfer goes up on the top ring and it goes down on the second ring. Can someone shed some light on this?
Second question, the same website suggests a minimum of .021 ring end gap, yet TMC suggests a minimum of .010 on top and .014 on second.
Thats a big difference. I know the bigger gap would do no harm, but it would allow more blowby.
I'm just trying to get it right.
thank you
bilorn
 

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5,100 Posts
Please do yourself a favor and call them.
I have some strong opinions on this topic but abstain.
The total seal ring (second only I assume) has some special setup of it's own.
 

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Premium Member
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Discussion Starter #4
Upon closer inspection, with bright sunlight, I found a dot on the second ring which places the chamfer down.
Only need to find out about end gap now.
thanks for replies
bill horn
 

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671 Posts
I would advise you to go with the instructions from the manufacturer. I just went through a nightmare 124" TC-B build with a horrible blow-by problem that ended up being the oil pump!
 
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