With those items left to cover this month, we’re going to put off the installation of the cylinder heads and leave the installation and adjustment of the valvetrain for next month, concentrating instead on the installation and inspection of the camshaft and to double-check our compression ratio to ensure we’re good to go next time. Note the liberal use of the aforementioned lubrication products having been applied before installation. Here, our Summit Pro SBC cam is being installed. There are things that are unknown until the pistons are in their place (deck clearance) and things that can vary (head gasket thickness), so it’s a good idea to use a product such as Summit Racing’s Compression Calculator to crunch the numbers and make sure we’re still in the green before it’s too late. We ran the numbers when we originally chose the components, but it’s always a good idea to double-check it as the engine goes together. But first we want to verify that our static compression ratio is going to be within the recommended specs for a street car, that is, under 10:1 for pump gas. Once the camshaft is installed, we will turn our attention to the cylinder heads. Comp Cams Cam and Lifter Installation Lube (Summit PN CCA-153) will be used on all the cam lobes, lifters, and other valvetrain components. Throughout the build we’ve been using Comp Cams Engine Assembly Lube (Summit Racing PN CCA-104) on all the bearing surfaces (crank, rods, and so on) and the camshaft journals will receive the same treatment. By comparing the results from degreeing the camshaft with the cam card, we can verify that the valves will open and close when they’re supposed to and the lift and duration is as advertised. This easy operation ensures that not only has the camshaft been manufactured according to the cam card’s specs, but also ensures that the engine builder didn’t make a mistake-a mistake that could possibly take out expensive components if installed incorrectly. Each and every camshaft is ground to achieve a certain event at a certain moment, so it’s important to ensure that those events happen when they’re supposed to after the camshaft and timing chain set are installed. In layman’s terms, degreeing a camshaft is the simple operation of checking that the installed camshaft functions happen as specified on the cam card. Summit’s Pro SBC cams are CNC ground using CBN diamond wheels from American bearing steel billets. With an advertised duration of 204 degrees on the intake side and 214 on the exhaust at 0.050-inch lift, our engine should have a perceptible idle lope with a good powerband between 1,500-6,000 rpm. To actuate the valves in our small-block we opted to go with Summit Racing’s recommendation of their Pro SBC Stage I hydraulic roller cam (PN SUM-8800).
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