The fun begins.....

[Flying Frank]

Both front wings off now to reveal ....lots of welding required .

[ChrisG]

where the oil filter is there's a thick aluminium 'block' about 7-8 cms thick. In effect it's a very small radiator. There's a black rubber coolant pipe in and out.
When the engine starts from cold the engine block coolant flows through these and the 'cooler' block , initially helping to warm up the oil that is passing though this block , and once the thermostat has opened the block receives water from the coolant circuit helping to cool the then hotter oil. Well that's the theory!
In the early ADI days when I did track the car a few times the oil temp did rise to about 130 on the gauge, never been anywhere near that on the road.
If not raining tomorrow I'll get a couple of pictures.

The block can corrode internally and the oil/water can then mix.......
I replaced mine about five years ago, just as a precaution ( cost about £25 iirc exchange )

[ChrisG]

I've seen much worse pictures than these !

[styler]

keep the original engine!!!! just give it a quick once over...

[Flying Frank]

Thanks guys for the info on the oil cooler and the advice on the engine. I'd like to keep the car as original as possible so using the early DZ engine which also has less miles under its belt is appealing.
Do you happen to know if the ancillary equipment, ( distributor, fuel metering unit , etc ) is compatible between the engines or was that also changed/modified ?

[styler]

theres a lot of little changes from year to year, same things with different shape connections and the like.. but the majority is the same, or completely different.. i found that out the hard way a couple of times!!

[Steev]

Keep the original engine Frank!!!!

do the other up as a spare by allmean.

you will kill the provenance if you shove another lump in there

my 72 coupe was not as bad thought ende up just honing the liners, just double check and if not then replace, it will pay dividends

[type81]

[quote=ChrisG;373190]not quite iirc,
I believe that ;............


Yes,.....what i meant by typ81 and typ85.....i meant prefacelift and facelift.

[type81]

Ive driven both the typ81 and typ85 80 Sports, the typ85 was slightly quicker...had a little extra pickup through gears.

Both we're quick though....typ85 a bit more eager
But Also tappetty from its hydraulic head.

My choice would be to keep the original engine in, but its your choice..and cost consideration etc

[Hanuman]

I'm actually of the opinion that you use which ever engine gets you up and running with the least distraction.
If it were a restoration for sentimental or investment reasons alone, then originality is important. But if you want use it, then that's the main focus.

With 2 engines available, it takes the pressure off, somewhat. If the spare engine will go in with the minimum of fuss, great.

It might be worth having a closer look at the existing engine.
Long term poor storage of aluminium heads- porosity can lead to coolant leaks. Both engines may be at risk.
Valve guides,and especially seals would probably benefit from attention.

The original engine is opened up. How are the bores?