Common Piston Failures.

What a great video. Learned something new, now I have question I can ask

Yeah, good videos.
A question that I have (and probably tight lip info per engine builder) is ring gap setting.
As the oem VQ37VHR has a ring gap of .0091” on 1st & 2nd ring.
As the VQ isn’t normally boosted & looking over boosted recommendations of similar engines, such as a VR38DETT, ring gap setting on e85 is (bore x .005) 1st & second rings- up to 15lb boost & (bore x .006) 15-30lb. That’s (.018-.022) on 1st & 2nd rings.
Make you wonder how boosting stock bottom ends & making big power over long periods of time is capable...engine must be very forgiving.

I am looking for info on a closed deck block. The benefits and pitfalls. Maybe I can find something good here also.

There are few good videos on line. I did a search a couple of years ago. If nothing else there is a reason GTR motors are closed deck from the factory. Maintaining cylinder bore tolerances/block strength and heat dissipation are couple of reason in my memory serves me well this morning. Hopefully I'm not have one of my moments again lol.

Need phunk to chime in. He would have the answers most likely.

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I have built both a 9:1, and an 11:1 comp ratio engine for my car now. Spent 3 years running down the 3.7L open deck block record at 850whp on my 9:1 engine. I tried literally everything. Different head gaskets, thicknesses, gasket coatings, clamping loads, had the heads O-ringed(final engine was a culmination of the three.). 8 head gasket sets, 2 blocks, and 8 connecting rods later I called it quits July of ‘17; when I lost another head gasket set after the dyno in may. Finally broke down, and invested in a closed deck block. Wasn’t until I took a stone to my old deck surface that I realized the there indeed are very noticeable high and low spots that form from cylinder expansions that are happening under high boost pressures. At the end of the day I’m telling you, one memeber to another, I don’t care who says what or what they think they know; your car WILL blow head gaskets over 800whp if you choose not to support the cylinder from shifting in some shape or form. 1Life the dynosty built haltech car did it at 820whp which is why he had his engine rebuilt, and purposefully turned back to 780-790.

FYI Charles is not looking to push Justin’s built car without some sort of cylinder reinforcement(whether that be dowels, inserts, or a block fill time will tell); they are merely using Justin’s car as a test bed to run the GTR head bolts which are currently being used on R35s well into the 12-1300whp realm. Not too bad considering the set of 16 can be bought for less that $100.

That's some nasty gas cutting there. Wonder where the line was before needing cylinder reinforcement.

Rid3_Famous, that is exactly what I needed. Data. Guess I will be opting for a closed deck block.

It's insurance. Why take chances for your power level.

Rabbit hole.

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I think we are all interested in phunks experiment.

We have theories and ideas. None of it is worth more than anyone else's until it is accomplishing something.

I am not opposed to the closed deck conversion. I might prefer to try it with the support structure resting a bit below the deck rather than right at it.

I believe that there is a problem deeper in the block, literally. Cutaways of a VQ demonstrate IMHO some concerning lack of girth and doubt about its ability to hold its shape under extreme torsional loads. There is no limit to what can be done to address it, but the real question is, how little can we get away with?