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A while back we saw a block failure at the ~700rwhp level on Chemvolt's engine. Here is another failure from toymanf's engine. This engine was doing it's first competitive 1/4 mile run.

Toymanf is not sure how much power he was making on the run, but the dyno he was on while getting the engine set up gave 540rwhp on turbo only (all subsequent runs were done with the tires spinning on the dyno) and the 1/4 mile run on which the engine failed was running that plus a 200 shot of nitrous.

The tune was conservative and you can see that there are no signs of detonation on the piston or cylinder walls. EGT temps were fine. AFRs were in the 11s. Fuel was C16.

The block was a seasoned stock block, bored 40 over. A 1.6mm HKS headgasket held down with ARP studs torqued to 65ft/lbs. It appears that the corner of the block around the #1 cylinder was unable to hold the lifting force that the head was putting on it.

There was at least another 100rwhp left untapped in this engine, but it is unclear at this point if the 3s block is capable of holding that much power over the 1/4 mile.

Any thoughts on how to contain +700rwhp power levels and keep the block intact? Sleeves would not have helped here. I've heard of using 1/2" studs but that is going to require a lot of work and I'm not sure if there is enough material in the block to make that work. Would the 5s block more reliably accept this much power and more?

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