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The block was sent out for a cleaning, overbore, and line-bore, and the crank was undercut to remove the scratches. New bearings and pistons
The call was made to upgrade to a COMP Cams roller cam for better power and reduced risk of flat-tappet cam issues.
The cam is grind XR264HR, which is a hydraulic roller grind designed for daily drivers, with advertised strong torque and a smooth idle. The specs are:
Intake / Exhaust Lift: .487 / .495, Intake / Exhaust Duration: 264 / 270 Degrees, Intake / Exhaust Duration @ .050” Lift: 212 / 218 Degrees
It’s not a high-lift cam, but we needed to keep the package happy with the stock 1978 cylinder heads and intake manifold. We were not out to build a racer, but add some torque to make it more fun to drive.
We installed a new timing set as part of the kit, and the roller lifters require shorter pushrods as well. The heads were in good shape, so we cleaned ‘em up and swapped the valve springs for a set that was better matched to the cam and put them all back together.
All new ARP hardware was used, including cam bolts, rod bolts, main studs, and head bolts. The water pump impeller to housing spec was checked before reinstallation. A new oil pump and pickup were installed.
The rod and main clearances were checked upon reassembly, and all was deemed good to go. The engine was cleaned, masked, and prepped for paint.