I have a brand new set of rings Hepolite no 23416 for my 3.5 rover engine, but there is no way they will fit the grooves. My 1972 Hepolite catalogue says they should be 5/64" thick. I have the remnants of at least three sets of pistons but these rings dont fit any of them.
Did they change the thickness sometime after 1972?

I have bead blasted a piston perfectly clean but the ring grooves are only about 1.6mm where the rings a 5/64" is nearly 2mm

Real Steel list 1.6 mm rings for the SD1 R/R engine 1976> in their Rover V8 parts list.

Real Steel - Performance Automotive Products


Rover V8> S1/3.

hth

zzr

davep said:

I have a brand new set of rings Hepolite no 23416 for my 3.5 rover engine, but there is no way they will fit the grooves. My 1972 Hepolite catalogue says they should be 5/64" thick. I have the remnants of at least three sets of pistons but these rings dont fit any of them.
Did they change the thickness sometime after 1972?

Click to expand...

I take it you tried them in the bores.

I dont agree with rings, if it's down that far best to go the extra mile and bore it and fit new pistons. Rings can cause so many problems and all that time and money spent just to be dissapointed.

So much work to do an engine properly, and I'm not sure on this but bead blasting sounds hellish agressive for pistons, particularilly so if you have cleaned out the groves as well. Most that I have attacked them with is a bit of wet and dry with some brake fluid, and keeping the carbon on the outsides of the pistons. Or the broken ring as described keeping the groves square.