[jim_howard_pdx]

You must run the scrapper AND I SCRAPE BOTH SIDES!!! You must run a windage tray. You must run the girdle. That block you are using should be good into the 7's.

I suspect that the NOS is the cause of the block damage.

You might want to change cranks just to be safe. I would ask a couple of Ford Motorsport dealers what they use in the 8 second brackets. Expect to pay 1,000 to 1,200 for the critter but it will resist the wrap up that causes this kind of damage.

If the problem is with the nitrous then here goes my favorite fix.
I hate giving up all my secrets. SO KEEP THIS TO YOURSELF.

When you run NOS it is especially effective to run a water injection system. I use a 5 gallon container, marked water in the trunk. It is plumbed with 3/8 inch lines and fed with a fuel injector type fuel pump. I am after 50 ppsi. I run the water at a 70/30 blend with pure isoprophyl alcohol. Iso is 132 octane.

I run this into two brass plant fogger nozzles that I mount just below the K&N filters. When the water flows, it gives off what looks like FOG when they spray. The pump delivers a set volume when the NOS hits. I use up about 2 1/2 quarts per quarter mile. My pipes are clean, my heads are clean, my exhaust temperature drops 145 degrees, my combustion temperature drops 278 degrees, and detonation is a thing of the past. By the way, the water allows me to run 13.5 to 1 compression with the NOS but I COAT THE PISTON TOPS AND THE COMBUSTION CHAMBER to get away with that. This is risky business with NOS going above 11.5 to 1.

I think you are detonating but it may be oil starvation. There are some trick accumulators out that will store up to two quarts of oil. I use these on off shore race engines and about any off road racing engine. It is especially good for turbo cars cause when the pressure goes to zero, the oil flows from the accumulator back to the main oil gallery. If you were oil starved I would expect you to have a burned engine. Lots of blue on the rod caps. Lots of weird wear on the bearing surface and rod journals.

I do not think that your wheel stands caused the crack. However, I do recommend that you NEVER LIFT during your launch. If you take your foot out of the gas because the front keeps rising, you can end up cracking a block. I have seen that on the Chevy small blocks.

ALL 9 second cars are going to pull the tires off the track. If it doesn't happen you are in trouble. Something is broken or wrong. If you keep your foot in the throttle you will come down soft and without any control issues.

My NOS systems are always PROGRESSIVE. I run about 200 hp on the first circuit and 375 hp on the second. That means two NOS tanks, two blankets, and lots of extra lines and hoses. We pulled 1100 HP and ran a 7.23 with a merlin block/heads/intake/ and single dominator carb. This is faster than the top fuel dragster times in the early 70's and they were running 396 or 426 Hemis with big blowers and fuel injection. Man how things have changed.