The engine is a 1998 4.0 litre Range Rover model, of the new cross-bolted variety.
Having stripped it for inspection and found it to be in almost perfect condition, but still decided to:
De-coke the pistons and rings, replace all the shells and valve oil seals, port the heads, and fit a Piper 285 cam kit while I was at it. I had to buy new follows and rockers anyway as these did not come with the engine.
An engine stand is a must, as will be the hoist to get it off the stand.
I elected to go for port matched heads, taken out to full gasket size to match my ported FI system.
The valve throat area was cleaned up and flowed and the combustion chambers valve area un-shrouded.
Un-ported on the left and the modified inlet on the right
Inlet port which has been flowed and the combustion chamber de-burred
I am using the new style distributor less front cover with crank driven oil pump and serpentine belt set-up. The four double-headed coil set-up from the late Range Rover is very neat and is driven by a 36 minus 1 pickup machined and fitted into the SD1 flywheel.
Multi-coil direct ignition
The new type cover is causing me major headaches. Its deeper than the older SD1 set-up, but with shorter pulleys. First problem is it fouls the standard steering rack, but as I am fitting a powered steering rack it has been mounted lower to clear. Secondly the water pump has a reversed rotation, so the belt runs under the pulley, therefore the set-up requires a minimum of 4 pulleys to have sufficient contact on the belt. Now that I need a powered steering pump that should give me the 4th pulley.
Latest type distributor less cover
The latest front also uses a longer sump of which I have acquired an alloy version, which has wings that support the normally open 2/5th of the bell housing. There are intermediate covers which have a distributor drive and use the new oil and water pumps, but are dimensionally similar to the older covers.
Alloy sump originally intended for automatic model
Unfortunately the bolt pattern on the new sump does not match the SD1 bell housing, so I had a bridging plate machined up. One of the sump wings also needs a cutout for the clutch slave cylinder.
Bridging plate