11. The solution is this GM flywheel spacer (part no. 12563532- $54.69) and flywheel bolts (part no. 11569956 - quantity 6, $3.47 each). This plate makes up for the thickness difference between the LS flange and the old Gen I small-block flange. It also keeps the torque converted centered on the crankshaft.
12. With everything ready, the 5.3 is dropped into the Caprice. It was amazing how easily the LS-based motor fit into the space where the 305 used to be, and even gave us some extra room in the engine compartment.
13. The factory exhaust manifolds on the 5.3 won’t work in this setup because the outlet is in the wrong place. The easy solution were these Hooker conversion headers for a second-gen Camaro, part no. 2471-1HKR. The car already had a dual exhaust system in place, so all we had to do is trim the pipes back to mate with the headers, and viola!
14. We did run into one problem, though. The driver’s side header hit on this ear on the transmission bellhousing.
15. Another easy solution: We just cut the offending ear off. After that, the headers cleared with no problem.
16. With the engine in place, we could start bolting on the accessory drive using Holley’s accessory drive brackets. First up was part no. 21-3 for the alternator. The bracket is a two-piece design that bolts to the front of the block on the driver’s side. The alternator is a standard late model unit, part no. 01-1748X, from O’Reilley’s Auto Parts.
17. Next is the bracket (part no. 20-131) for the AC compressor. The Holley bracket uses the same R4 radial compressor the Caprice came with stock, except it relocates to the passenger side. Because we’re converting from V-belts to a single serpentine belt, the compressor for an ’88-’95 V-8 full-size Silverado is used.
18. The intake we’re using is a dual plane Edelbrock Performer RPM LS1 (part no. 71187) that comes with a dual bolt pattern to fit either Edelbrock or Holley flanged carbs. For ignition, we’re using MSD’s stand alone LS1/LS6 ignition controller, part no. 6010. It’s designed to just run the factory LS coil-on-plug ignition, using the stock crank and cam sensor.
19. Because we’re using a carb, the Caprice’s factory throttle, TV, and cruise control cables can still be used. This new cable bracket came with our intake, and installs like so.
20. The MSD ignition controller is an almost entirely plug-and-play unit. The simple harness it comes with has one master plug that bolts into the control box, then eight plugs that run to the ignition coils, plus one to a MAP (Manifold Absolute Pressure) sensor in the intake.
21. The Edelbrock intake already has provisions to mount the MSD MAP sensor here. A MAP sensor measures the vacuum pressure inside the intake manifold, and along with the RPM reading of the engine, tells the ignition to either advance or retard the timing.
22. To power the ignition, this main pink wire from the new ignition harness is run to the pink wire on the factory coil plug. This supplies the ignition with key-on power.
23. For the cooling system, you can use the stock radiator. First up is a new upper radiator hose, Gates part no. 22436, which is spec for an ’99-05 4.8/5.3 Silverado.