TR2/3/3A 89mm pistons TR3

[tinman58]

I am assembling the TR engine and we got to the new 89mm pistons and noticed that the #2 ring has a groove on one side and there is no info on which way does the groove go? up or down?

 

[JohnB]

Dan,

I'd be calling the manufacturer on Monday, just to be safe.

 

[TR3driver]

Is the groove at the inner edge, middle, or outer edge of the ring? If it is middle or inner, it goes up. If it is on the outer edge, it goes down.

https://www.hastingsmfg.com/ServiceTips/compression_ring_installation.htm

 

[tinman58]

Randall! You are the Man!!
In your attachment my ring looks like the bottom diagram. The engine rebuild will continue tomorrow.
Thank You

 

[MDCanaday]

Are the liners the same as the standard liners?? I would think they would be a little thin near the lands if they were not special....what is the difference if any.
MD (mad dog)

 

[tinman58]

MD
The liners look the same and fit in perfect. If you do the math, from 87 mm to the new 89mm would only be 1mm in thickness of the walls. But don't ask my wife the logic in 2mm of diameter for $850. Woman don't understand!

 

[TR3driver]

The logic is that the 89mm liners are a better alloy than the 87s, and custom made to more exacting tolerances. The pistons are also custom, and I believe the ones I got were forged rather than cast.

Yes, they are pretty thin where they spigot into the block. But really, that area doesn't need much strength; the liner will be clamped in place between the head and the "figure 8" gaskets, and the rings don't go down that far; so the lower portion really only serves as a guide for the piston skirt.

Mine were also made in the USA, rather than outer Junkistan.

 

[tinman58]

Outer Junkistan? I think I bought a 1980 Chevy Camaro that was built in Junkistan!