picking up where i left off with building the powertrain R&R cart, i measured from adapter plate to side mounts and tied it together with angle:
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then i checked clearance to a piece of 2x3 which i'm going to use for engine crossmember. perfect! the cart will be used to hold crossmember for welding to unibody.
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but once the crossmember is welded into the body, how do i get the cart out? scope creep, that's how! i added a receiver to the front of the cart, that allows easy on/off of the front mount support (circle 1 in pic below). with front of engine supported here, i can roll the cart back 4" before it crashes with crossmember. but then i'll slide the adjustable side-mount supports into their receivers (circle 2), and detach the front mount support.
to locate the cart fore-aft on the powertrain, i added tabs to the back of the rear cross beam and blocks to the top (circle 3).
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adjustable side mounts? Why?
i'm glad you asked. The adjustment means they can be used to take the weight off the front mounts so those bolts are easier to align and run in or out. They also allow for height adjustment and side to side leveling as I attach the crossmember. They started life as new tie rod assemblies for the Sonoma. Cut off the threads, turned the cut end to fit a 1/2" ID tube, and welded up, probably spent eight hours of garage time making those.
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it works exactly as intended and, with the powertrain at the right height, i was able to install the C5 rear suspension cradle to verify clearance to Audi transaxle. Result: \m/
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a fun coincidence which i wish i could claim as design intent from day 1: the XSPower turbo headers (thanks Patrick!) exit almost perfectly centered between the package tray above and the C5 frame below.
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and here's one of my favorite views of this project to date:
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tonight after work i can *finally* begin engine crossmember installation.