The folks at Horse Power Sales say a stock two-bolt 5.0 block survived 9,200 rpm, thanks to its Valley Girdle ($229). That's a pretty bold claim, but at the time we were revamping our project car, the real Real Street guys were regularly surpassing 7,500 rpm. They, however, have expensive, rugged race blocks. We didn't want to replace our trusty D.S.S. Bullet until we had to, so we figured, why not add the Valley Girdle? Our block already features D.S.S. Main Support, so we could see what a stock block with support from top to bottom is good for.
Installing the Valley Girdle isn't too tough, especially when you already have the intake and cylinder heads off as we did. The first step is removing the lifter spider's retaining bolts and using the longer bolts supplied with the Valley Girdle to fasten it in the center. Then you use the girdle's holes as a guide to drill into the block. It sounds scary, but it's not too bad. Just make sure you capture all those nasty metal shavings-you don't want them floating around in your oil. We changed our Royal Purple just in case.
With the holes drilled and the area cleansed of metal, simply tap in two dowel pins to hold it securely in place. HPS says the Valley Girdle stabilizes the block and reduces cylinder-bore and lifter-bore distortion, which could lead to block failure. Reducing such friction should also free a bit more power, but we'd be happy if it just makes our already-bolstered stock block even stronger.
With the Valley Girdle in place, we dropped on our Trick Flow Twisted Wedge heads, which feature Anderson Ford's Real Street valve job and those new springs we talked about a few captions back.
Then Mark torqued down the heads and quietly hoped to himself that Turner didn't blow another head gasket so he wouldn't have to "help" him anymore.
Here's where we wished we'd waited on those new NMRA rules. Not that it's a huge deal, but we reinstalled our previously legal AFM/Bassani 171/48-inch short-tube headers. These babies have proven good for a bit more power than short-tube headers with traditional 151/48 primary diameters. Hence, only the 151/48 headers are legal these days.
At least we resisted the urge to move to shaft-mount rocker arms. We stuck with our 1.7:1-ratio Comp rockers, which was a good move because the shaft rockers are now illegal.