Metro Turbo ring gaps
Turbo Mini Forums

Does anyone know the tolerances for the Metro Turbo ring gaps?
I've measured mine at 21 thou for the top ring and 16 for the second.
No difference between the top of the bore and mid way.

16 seems a bit loose for the main compression ring but I'm not sure it's worth replacing them as they're not miles out.
All thoughts welcome!

The top is the main compression ring.....which you say is 21, not 16.

And typically the 2nd ring would have a larger gap than the top ring.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Yes, I’m aware that’s the wrong way round. Top ring will see more heat, so maybe that’s why?

Why should the second ring gap be larger than the first? Seems to be a theory from the 70's.

4:40
https://youtu.be/OFtf7l0B3kM

Edited by Steve220 on 7th Jun, 2021.

thanks Steve - interesting video.
I'm probably going to order some Total Seal rings... although I've still got no idea whether my old ones are out of tolerance or not...

70's ? Engines are engines...ring design depends on whether you want larger or smaller gaps 1st/2nd as well as materials etc.

As to whether they are out of tolerance....are they original factory items that have never been touched to deem they were in tolerance ?

Rings generally need gapped to suit each specific application.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

70's ? Engines are engines...ring design depends on whether you want larger or smaller gaps 1st/2nd as well as materials etc.

As to whether they are out of tolerance....are they original factory items that have never been touched to deem they were in tolerance ?

Rings generally need gapped to suit each specific application.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will