Engine Positioning, Chassis Prep and Installation

Engine Positioning, Chassis Prep and Installation

While I was waiting for all the drivetrain parts to appear, I was also working on stripping out the old Toyota drivetrain and prepping for the Chevy V8 install.  Engine out was easy.  Disconnect half dozen wires or so, remove transfer case and transmission as one unit, pull radiator, battery, pull engine.  Done.  The only tool I bought was a Harbor Freight 2 ton engine hoist which I split with a buddy who is also doing an engine swap in his hot rod.

Before:

After:

It’s Lump:

I bought the Advance Adapters engine installation kit (AA 713124) for the swap.  Looking back, I wouldn’t do that again.  The kit was relatively expensive and only o.k.  I did find the directions helpful though.  The installation guide states the engine should be position 8-12 engines behind the shock tower.  The stubby little scab plate they provide is only 7 inches long (if I remember correctly) and would require you to locate the engine precisely before welding them in.  I did this.  What a waste of time.  The ends of the scab plate fell over two of the cutouts in the OEM frame rails so I would have lost about 5 inches of mediocre weld length.  And I need all the additional I can get.  I went and bought some 4” X 3/16” Flat Steel and cut two 17-1/2” pieces.  This length fell midpoint of two of the cutouts for welding convenience and would allow me to position the engine mount pretty much anywhere.

After cleaning out the engine bay, cutting out the old mounts and stripping the paint, I noticed two of the rivets holding the original frame together on the driver side near the engine mounts were loose and spinning in the frame.  My guess is that this is not good for structural integrity.  To remedy this I welding the “C” channels together top and bottom about an inch past the scab plate I planned to install. 

Crappy weld job:

After prepping and welding the channels together I then welded in the home made scab plates.  I added four ½” plugs as well, because ½” is the largest drill bit I have.

The next part was to locate the actual engine mounts.  The AA installation guide and internet wisdom say you want a 3-5 degree angle, tail down.  I don’t have an angle finder, and I think it is easier to work from level so I dug out my geometry skills.  I raised the tail 7 inches for about a 4.5 degree angle.  I then did some internet digging to find my lift springs in the front are about a 200 lb/in rate, so when the drivetrain is installed it would lower just over 2 inches.  Net result would be somewhere between 3 and 4 degrees.

I put the truck on jack stands and worked off of level from there: 

I then rolled the transmission under and lifted the engine over, bolted the two together and placed them.  I chose to push the engine as far forward as possible and maintain driveshaft length.  Well, the new drivetrain is much too long, so just plan on cutting your rear driveshaft.  Don’t forget to install the radiator when doing this so your fan doesn’t interfere.

I positioned the engine mount 9 inches back from the edge of the shock tower to the centerline of the mounting hole.  Leveled the mount, held my breath and tacked it in place.  I then positioned the opposite mount in the same location along the frame, leveled it front to back, and leveled it across to the other mount to ensure they were coplanar.   I placed the front edge of the mounts level with the top of the frame.  If I planned to do extreme rock crawling, I would have raised it as much as possible.

After tacking into place, I refit the engine and radiator, verified clearances, pulled everything back out and then finished welding.  One thing to note is that I plan to mount my engine on centerline of the chassis, instead of offset.  I did not notice any front driveshaft interference with the bell housing until extreme font axle travel.  If I run into issues later I will shift the engine or lower the bump stops.

In the end I am pretty happy with the result.  The crankshaft pulley to electric fan motor is a bit close, about ½”, and the Orion transfer case sits right about 2.5 inches below the frame.  I will brace the radiator, as per the factory, and build a skid plate for the transfer case.  Even hanging below the frame, with the lift is measure 18-1/2” inches from the ground.  I think there is some good clearance.

Final Install: