RPM PROJECT CAR before race day! Advice Forbes and his guys are taking to heart. When last we met with our “Revival” project in the pages of RPM, we set the stage for the build and saw substantial chassis work completed, some trick custom parts being made (because they can), and a basis for the engine start to come together. Forbes had acquired an aluminum 6.0L back in 2011 with low miles but when the decision to go street/ strip with a plate nitrous kit was made, it was a conversation with Matt at Induction Solutions that made him realize the aluminum block was not going to hold the power. (That conversation ended with the order of a Saturday Night Special nitrous plate system good for 300hp and wet flowed prior to shipping, but we’ll discuss all of that in a future issue). The aluminum motor sold quickly and Forbes scored that junkyard LQ4 iron 6.0L block we showed you
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in July to build on and promptly contacted Eagle with regards to a stroker kit for 408-inches that would enable him to use the LS3 heads on the LS2 block. Now that’s cool! “We turned to Eagle for a rotating assembly,” said Forbes. “We wanted to keep this engine simple by using as many OEM-type parts as possible, or as close to bolt-on as we could. The L92 head swap is a common upgrade for making power. Right out of the wrecking yard you get stock head flow numbers that far outflow really good SBC numbers, so how can you go wrong?” Eagle Specialty Products, Inc. makes a direct swap rotating assembly for the 6.0L L92 Swap. With a 0.005-inch over piston size, it is a no brainer to add some cubes. Forbes opted for .030inch over to ensure a good ring seal on his high-miler block. An L92 head has a large 2.16-inch intake valve and only comes on a 6.2L with a 4.06 bore. Being able to put these
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on a 4.00 bore and have valve clearance with a big cam is why this kit is unique. Kit number 12946 will increase this motor’s CID to 408. The kit includes Eagle 4340 forged steel crankshaft, Eagle forged 4340 steel H-Beam rods with 7/16-inch ARP 8740 rod bolts, forged Mahle pistons with performance ring set, and premium rod and main bearings. The rotating kit is unbalanced but Forbes opted for Eagle to balance the assembly at the factory. 4: The right tools for the job are essential—that, and the knowledge With LS3/L92 to properly assemble a street/strip engine. Like we said in our first cylinder heads the article…do what you can to save money for what you can’t do. compression ratio will be 11.1:1. So perfectly streetable. 5: Doing The block was things right sent to Forrest involves and Forrest Racing for some TLC. checking “We opted for the clearances, full spa treatment: then double hot tank, shot checking peen, 0.030”over just to be bore, line bore the mains, and 0.01” sure. off the deck,” tells Forbes. The TLC wasn’t limited to one trip to the
september 2017 | RPM Magazine
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