Hi There
The motor is equivalent to the Td27 counterpart, without the turbo, but still has all he same bungs.
you can get the td27t oil housing and use that for oil feed, or use the blocked of bung where the alternator oil feed/return would be.
the water drain block at the back bottom of the engine is just a bolt/bung (to drain coolant) on the QD, on the TD it is an adapter that goes to a bung and a turbo water line.
The TD water return goes into the bottom water housing, near where the hose is connected. Its just a tapped thread with a 90degree barbed hose adaptor on it.
the QD does not have this, but its easy enough to attach one (drill, tap thread, attach).
words of caution
wd21 td27t and R50 Td27t are same, but different :
they have different adapter on the oil feed bung, wd21 is some random thread, r20 is large metric and you can get speed flow adapters for it.
Turbo have different outlet directions as the r50 is inter-cooled.
They have slightly different water return locations. wd21 is the cold water pipe alloy casting and the r50 uses the top-hot water pipe alloy casting, near the thermostat.
The turbo manifolds are pretty much the same, these manifolds have a vertically angled T2 flange.
This is the same as the Silvia, however Silvia are Horizontally mounted. so when using a Silvia turbo it must have the core rotated to have the oil feed on top.
Skylines are close to Vertical mount, so it might work out close, but you would need a t2 to t3 adapter.
now the part you wont want to hear.
Stock turbo on the Td27 and the QD turbo models is a small frame Hytashi Ht12
this is equivalent to a Garrett GT20 frame turbo.
Your skyline turbo will be a medium frame Gt28 turbo, two whole turbo frame sizes larger.
I put a s13 gt25 turbo on a Td27 and it was alot of work. I think it was to laggy as it needed a heap of fuel to get her spooling corectly.
If you run with a t28 you will need to up the fuel and have the potential to run a laggy / high boost application.
If you only want to run lower boost, pick a stock sized turbo, as the diesel is useless with lag, you really want the power to be in the lower RPM where the diesel is pushing the most torque / power.
the gt20/ht12s would be good for almost 20 psi, but i would only run 15 or so.
The T25 only really made good power around 12+ psi, anything less and it seems lazy.
Any intercooler is going to be better than no intercooler.
id argue after all the work of getting the pipework done, you might as well get a corectly sized china core, it will preform better than a stock silvia core.
this is of cause if your going FMIC.
dont bother going TMIC unless your doing a W2A setup, otherwise it will just heat-soak during 4wding / going slow.
if you have any questions, just ask, ive already done all this before.
