Cranks Between Ring Lands

[MadBill]

.. Second rings are usually tighter anyway yes no?

Err... no. For the last decade or more the consensus has been that the second gap should be larger, to reduce the possibility of inter-ring pressure build-up that could unseat the top ring.

[piston guy]

Bill is correct, increased second ring gap reduces top ring "flutter" at higher rpm. Well proven fact.
OP's problem is still detonation related.

[fdicrasto]

Ok, question about 1st and 2nd ring end gaps. Why MORE end gap on 2nd ring? Does the 2nd ring get tighter at max temp than the top ring? Or is the top ring less prone to growing than the 2nd ring? Or?

[statsystems]

Ok, question about 1st and 2nd ring end gaps. Why MORE end gap on 2nd ring? Does the 2nd ring get tighter at max temp than the top ring? Or is the top ring less prone to growing than the 2nd ring? Or?

All rings leak under load. Anything that gets past the top ring will get trapped between the top and second ring and cause it to unseat the top ring.

Once any combustion gets past the top ring it needs to get down past the ring pack and be taken care of by the crank evacuation system.

[Warp Speed]

The wider second ring gap being beneficial is purely combination driven. IMO
Maybe for a wet sump type system in a mild combo, but in a performance engine, if that second gap being a few thou smaller is causing that top ring problems, it was already done to begin with.
IMO

[cjperformance]

Following most piston makers ring gap guidelines will put the top ring gap at less than the 2nd ring gap when up to operating temp simply due to the extra heat in the top ring area expanding the top ring more which takes up end gap.
At 'most' piston makers gap spec there is a reasonable safety margin before end gap butting is even likely.
If you worry about making the 2nd ring gap wider than the piston maker suggests you will be in most cases just going too wide and making the 2nd ring less effective.
The 2nd ring only sees excess heat either thru the piston becoming way too hot OR the top ring not sealing properly. Correct top ring application, material, gap, quality, bore finish and bed in is far more important than putting a few extra 'bandaid' thou on the 2nd ring IMO