Did a leakdown and comp. test on my motor today

[510six]

I did a leakdown and compression test on my 3 liter today and found #2-3 cyl were at 15% leakdown while the rest were at 4-5%. The compression test showed 150psi on 1-4-5-6 and 135 on 2-3 so it`s time for the motor to come apart.I didn`t hear any much air past the valves so I might have some broken rings(I`m guessing). I`ll know for sure when the motor is torn down, I`m just amazed it has lasted so well from all the abuse I have thrown at it.A friend with a VW running similar times has gone through 3 motors and I can`t imagine any Honda holding up to as many repeated drag launches as this motor has.

[technicalninja]

I would guess either

Broken 2nd rings or lands

Or slight headgasket blow between 2 and 3. I would look closely at HG before taking bottom end apart.

BTW- the 4-5% leakdown on your good cylinders is excellent for a motor that has been "applied properly".

[510six]

The motor had over 200 drag passes on N20 so I would imagine that the rod bearings would need to replaced.The Pistons are VG30dett types from JE with L series valve relives and Cunningham rods I don`t hear any indication of broken pistons so hopefully the rings are bad.Worst case senario is a new set of pistons and .5 millimeter overbore.I will have a valve job done as well since the motor is apart.The headgasket is a NISMO multi layer SS unit but with nitrous I could see the gasket getting torched between cyls.As the cyls are "O" ringed with SS wire it would have to be one serious blowout.I am thinking a piston would give it up first.But, one never knows.