Like virtually every other long-term vehicle project with which we've been involved, Project C4orce has had its share of detours, about-faces, and wrong turns. Frankly, it's surprising that this project has proceeded so smoothly, considering that we're not simply installing existing products, we're also developing new ones. (Which are or will be available for sale through a number of sources.) We're not trying to reinvent the wheel or develop high-tech methods for addressing square peg/round hole interfaces, we're developing components that either don't exist or don't meet our specific requirements or performance criteria.
As an example, motor mount adapters are required to install an LSx engine in any chassis not originally designed to accommodate one. Whereas a conventional Gen II or earlier small-block has three bolt holes through which each mount is attached, a Gen III or Gen IV block has four. A number of companies offer adapter plates, so we ordered a set with the intention of installing them, test fitting the engine in the chassis, and moving on to the next item on our "to do" list.
Then a detour popped up. The adapters we ordered bolted to the block and accepted the C4 motor mounts with no problem, but the machine work looked like something done during the first week of a high school shop class, and the adapters didn't position the block properly in the chassis. So we developed our own C4orce design adapter plates. Then Trey Hanson installed them, set the engine back in the chassis, and this time, everything fit properly. In theory, these adapter plates should successfully marry any LSx engine to any chassis that originally housed a Gen I or II small-block, or Gen 6 or earlier big-block. We're testing a number of non-C4 installations, so we'll soon have a list of engine/chassis combinations that are or aren't compatible. (Currently, these adapters are available through Speed Hound Performance and Vmax Motorsports.)
Another "problem" associated with installing an LSx engine in a C4 chassis was lack of headers. Although opinions vary as to their suitability, LSx exhaust manifolds that will fit a C4 chassis do exist. Stock manifolds are obviously less expensive than a set of long-tube headers, but they would have imposed a significant performance restriction. Unless you're in the business, building a set of headers is, at the very least, challenging, so developing our own didn't seem like a viable proposition. Fortunately, we didn't have to search for other options because Dave and Chris Wiehle of Melrose Headers had become aware of the C4orce project and offered to develop a set of LSx-specific C4 headers. Melrose's current product line includes both C5/C6 and C4 headers, so the obvious starting point for configuring a set to fit C4orce was simply a matter of modifying the company's existing L98/LT1 headers to fit an LS1/LS2/LS6 header flange.