TR2/3/3A 60 TR-3 Post 60000 Timing Chain Question

[Tinkerman]

Evening All: Technical question for you. I have a brand new timing chain on a new cam chain wheel mated with the original crank. Question of the day is how much stretch after break in can I expect from the chain? 5 thousands, 10? More possibly or less maybe?
Anyhow any thoughts would be greatly appreciated

Thanks, Tinkerman

 

[TRTEL]

It's always a function of alloy and machine finish. Had to replace mine when I bought my 3. The tensioner had broken and punched a hole through the timing cover. A friend, who was maginally less mechanically ignorant than I, said "you don't need that thing" meaning the tensioner. Since my budget was already comprised by buying a new Triumph chain. But it did fit very snug, so back together it went sans tensioner. When the engine got torn down about 4 years later it showed some stretch, but not that much. I did put it back together with a tensioner. On the other side of things, my brothers clapped out 62 TR4 got rebuilt using all JC Whitney parts. Most of which, as I remember were made in Italy, Yugoslavia, Poland etc. And when it to got rebuilt after 5 or 6 years, I do remember that chain probably had a world record sag in it, perhaps a half inch or more. Luckily most of the modern replacements I've seen are pretty decent and I don't think you'll have a worry. Don't get your cover welded though, that turned into the biggest leak I ever had on that car. I did not yet understand the concept of heat warping metal.
Tom Lains
TS8651 & 58107