You’ve got questions, we’ve got answers. We work with the Summit Racing tech department to help you tackle your auto-related conundrums. In this week’s Mailbag, we’re answering several questions about an Olds 350 engine build.
Q: I am building a 1977 Olds 350 that I will be installing in a 1976 Nova. The engine has 9.5:1 compression pistons, stock rods, and a stock crank. The camshaft is a Lunati with 224/234-degree duration at .050-inch and .496/.520-inch lift. The heads are stock, and I will be using an Edelbrock intake manifold and a 600 cfm Edelbrock carburetor.
I have the following questions:
1. Will the Olds frame mount bolt pattern match up with the Nova’s frame mount pattern?
2. What valve spring should I use with the camshaft?
3. Will this cam provide enough vacuum to run power brakes?
4. Can I use stock rocker arms and stock-length pushrods?
5. Can I use the stock oil pump?
A: Your parts selection looks good. Here are the answers to your questions:
1. You will need to use frame stands from a 1972 to 1976 Olds Omega. These will be a dealer or salvage yard item.
2. Use valve springs with an installed height of 1.800 inches with 100 pounds of seat pressure, and 295 pounds of seat pressure at 1.25-inch compressed height.
3. Vacuum to run power brakes might be a problem with your cam. Its 112-degree lobe separation will help boost cylinder pressure, but you may need a vacuum canister to store vacuum for the brakes.
4. Using stock rockers, pushrods, and other valvetrain parts will be a problem. When using a cam with more than .474-inch lift in an Olds, you must use adjustable pushrods or adjustable rocker arms. COMP Cams offers a conversion kit for this, which includes 1.6 Magnum rocker arms, rocker studs, guideplates, and COMP’s High Energy pushrods.
5. The stock oil pump will work fine for your engine combination.
