Ian, The cooler outfeed (ie return pipe) runs into the filter and through the filter to the engine gallery. The relief valve returns oil to the pump inlet and is separate to the oil cooler circuit.
That explains it then, we were both right:cool: the blocks are all the same sump flange and the front covers are different!
Regarding the oil cooler plumbing, in many RV8 instalations the oil filter is a problem poking so far fwd like it does amnd you usualy need to fit a remote filter, this is the way I found easiest to plumb the cooler in
Yes indeed it's the front cover that descides the sump type. I have two RV8's and like you one has a remote filter /cooler take off . On the other the filter space is not a problem so I will be using the OE oil cooler take off points on the serp type cover which gives a neat arrangement.
So will the 4.0 V8 manual flywheel trigger the ecu?
I'm using a manual box and the 4.6 was an auto so to save lots of grief I was wondering if it would be easier to use 4.0 manual flywheel to trigger the ecu. Just need to get it remapped