He doesnt have time for this "engineer" nonsense. He's installing a big bore kit and needs to raise the rev limiter to make MAXXX POWA!!!!
Here is something to consider. One of the premier big-bore high horsepower companies, Hammer Performance has a list of dyno charts and most of them shut off at about 7500 rpm, which is what I think the 2008 XB12's redline is.
If one of their highly tuned, high horsepower motors were making power after that, they'd be sure to show it, as it just makes them look better, and demonstrates to the customer they are making as much hp for their money as possible. But for some reason, they stop logging around 7K. There may be a reason.
Also, like what Sensei Barrett mentioned... the stock cams, valve springs and heads and other parts probably cant handle much past the stock redline, and neither can the bottom end. A few people have send their cranks to Dark Horse for reworking, balancing and other magic to push the redline higher. I think I still have a video of Magnesium Mike's ultra quick and high revving XB9 and its AMAZING.
The coveted race only XBRR only had a redline of 8400, but if you seem intent to raise the redline... go ahead. I need spare parts and the used market has dried up a lot.
I haven't even mentioned that you're going to have to keep the rev's down for at least the first 500 miles per the manufacturers instructions. Their engineers have determined proper break instructi.... ahhh never mind. EFF THEM AND GET ON IT!
In ECMSpy its under the "Limits" tab towards the middle, then the "Engine Speed" tab on the far left.
If you're setting it less than 10K, you've wasted our time.
and yes, John... you are an expert. I only stand on your shoulders, sir.