It makes things a lot easier if you bolt the transmission to the back of the engine before lowering the car onto the subframe, avoiding any need to futz with a trans jack in the cramped F-body trans tunnel. Now's a good time to install a new throwout bearing too. Carefully line up the tranny and gently slide it into the clutch; the transmission bolts get 37 lb-ft. | 
Most engine accessories can also be installed onto the engine while it sits in the cradle/subframe. Here we've already attached the alternator and are bolting on the power steering pump. Note that the power steering pulley must be removed for pump removal and installation, which is easily done with a generic pulley puller/installer tool (they're widely available). | 
Of all the conveniences the F-body's removable-subframe system makes possible, perhaps the best is the ability to install the wiring harness onto the engine and transmission prior to its insertion. The overworked/underpaid-looking dude you see here is viewing a pre-removal photograph (perched atop the strut) for guidance on where all of the wires are to be routed. We'll also note that while the engine has been out of the car, the A/C compressor has been left hanging under the vehicle; you can see it above said dude's head. This avoids having to decompress the system and buy new R-134a (along with getting moisture into the A/C system and possibly destroying it). |
Time to lower the car onto the engine! You'll definitely need an assistant or two to help, as someone needs to operate the lift while another makes sure the cradle is going in straight. Many fine adjustments to the location and pitch of the cradle will be needed as the vehicle is slowly lowered (small wooden blocks are a big help); use extreme care to make sure nothing gets crushed, bent, pulled, or otherwise screwed up. Areas of particular note to watch are the steering shaft and twisted mess of brake lines near the driver side strut tower; they'll need to be lined up and slipped into place as the car is lowered. Botch them up too badly, and you'll be dropping the subframe again! | 
With the right amount of finesse, the dowel pins in the cradle will line up with those on the frame and the cradle can be attached (only six major bolts hold it in). This is the mess you'll be left to deal with once the engine is in place: a not-insignificant portion of the wiring harness, currently piled atop the intake, must be snaked over to the computer location behind the passenger side front wheel. You'll also need to connect all coolant hoses, bolt up the A/C compressor, attach the torque arm to the back of the transmission, and reinstall lots of other little things before you're ready to run. | 
As the inlet location for the Speed Inc. fuel rails is at the front of the driver side rail, the OEM rubber fuel line won't work (it's attached further back on the stock rail). Since we're leaving the purge canister system functioning on this vehicle, we separate the rubber fuel line from the fuel vapor line by delicately slicing the heat shielding wrapping them together. |
The stock rubber fuel line segment is removed from where it connects to the factory hard lines adjacent to the shock tower using a 3/8 fuel line disconnect tool available at just about any auto parts store (it's just a small piece of plastic). You can see we've cut the correct length of braided line, attached its fittings, and are now tightening it to the fuel rail inlet. Speed Inc.'s included LS1 Feed Line Quick Disconnect Fitting enables the finished line to snap directly onto the factory hard fuel line coming from the tank. As to the front of the passenger side rail, Speed Inc. supplies a plug for it; but since our nitrous system needed a fuel source, we acquired the appropriate adapter fitting locally (only $6 for a steel 3/8 to -4 AN). | 
After pouring in 5.5 quarts of 10W-40 Pennzoil conventional oil (see our discussion of break-in fluids and procedures next time), our Speed Inc. helix-mount breather is then affixed to the passenger side valve cover. The polished aluminum mount is twisted in by hand (a strap wrench may come in handy) and the breather simply pops on top. This washable breather comes off easily for when you need to add oil, yet stays put thanks to a beveled edge machined into the inside of the mount. | 
We found that the stock throttle cable bracket wouldn't work with our new Holley throttle body, as it sat too far back to allow the throttle to completely close (even messing with the cable adjuster wouldn't give us enough slack). Never fear: Holley's provided throttle cable bracket (absent from our previous photo thanks to us "misplacing" it) provides the solution. It bolts not to the molded-in location on the manifold, but to the upper left throttle body bolt and the front intake bolt. This moves it forward enough to allow the cable to properly reach. Holley also includes a longer bolt and spacer to move the throttle cable bracket even further forward if need be (nitrous plate being used, etc.). |
Home at last! After a few final adjustments to get the airlid and MAF on properly with our new throttle body, this 383 LS1 is good to go. You can see fingerprints and hastily routed wiring lingering here and there, but we're not looking to hit any car shows right away: we want to get this sucker running, tuned, and ready to kick ass! Hate to leave you hanging, but make sure you pick up a copy of the next issue of GMHTP for full dyno and track results, a breakdown of all the parts and funds we spent on this project, as well as a synopsis of computer tuning and other issues that go along with any new engine. | | |