I am REALLY interested in the PHYSICAL FIT aspects of this project, as my buddy and I are about to start to try to fit a GM LQ9 6.0 liter engine (identical external block and most other parts to your engine).
I bought, from Street and Performance, their LS engine adaptors that adapt the LS engine block to regular SBC mounts, their bolt-in SBC mounts, and their tubular transmission crossmember (all these parts are actually made by Chassis Engineering).
The info I got from them is that the steering box clearance will be too tight, and that the steering box will need to be moved over about an inch, which is apparently not difficult and is workable. The exhaust clearance will also be tight, so we are prepard to go with anything from stock exhaust manifolds to tight clearance headers or whatever can fit without too much hassle.
We know that clearance at the front will be very tight because the LS series engines require several inches for the FEAD (front end accessory drives), and because we need to fit in a combination radiator / tranny cooler / AC condenser / shroud / electric fan. We will take some measurements once we get the engine roughly positioned.
The back of the engine on the LS is WIDER and HIGHER than the smallblock, due to the clyinder head corners. So, even though the distance from a reference engine mounting bolt hole to the back of block is 1" shorter on the LS series engine than on the SBC, we have asked the body shop to dent the firewall back just a bit.
If you have to CHANGE FEAD, the costs go ballistic, as GM offers only 3 variants (Corvette, Camaro/Firebird, or truck), and if none of them work, the after amrket ones START at over $2000 (no kidding). So, we want to try to avoid that.
We know already we will need a different (shorter) AC compressor, as the LS engine mount adaptor plate comes too far forward to allow using the stock 6.0 liter compressor in its low passenger side mount position. A shorter compressor will fit via mount adaptors.
How far back did you mount your engine in the chassis? (Use some easy-to-identify reference points, if you could, like middle rivet in the front crossmember to a clearly defined point on the engine mount). The instructions we got, which apply to the SBC, say to position the CENTER of each actual rubber engine mount bolt 15 1/8 inches rearward from the center of the middle rivet. Is that where you are, or somehwere different?
Jim G
