second image red arrows showing proposed coolant bottle connections (from engine to bottom of coolant bottle and radiator to top)
cooling system hooked up (no clips, just setting up pipe work), does it look ok?
second image red arrows showing proposed coolant bottle connections (from engine to bottom of coolant bottle and radiator to top)
Connections to header tank will be fine,as long as that one on the block is pulling coolant into the system,not pushing it out 
Don't know the engine sorry so don't know how the coolant circulates!
Rad connection looks good. I don't use an expansion bottle on mine (E36 M3 engine), don't have any issues with this arrangement - I end up
with 5 cm of air at the top of the rad but it works and cools the engine just fine. It is a bigger rad than you've used though.
BTW I have a spare 11" fan (Spal) if you need one? (I switched to using a suction fan because of moving the oil cooler in front of the rad).
quote:
Originally posted by rodgling
Rad connection looks good. I don't use an expansion bottle on mine (E36 M3 engine), don't have any issues with this arrangement - I end up with 5 cm of air at the top of the rad but it works and cools the engine just fine. It is a bigger rad than you've used though.
BTW I have a spare 11" fan (Spal) if you need one? (I switched to using a suction fan because of moving the oil cooler in front of the rad).
I used an uprated Ali polo rad in my m3 Marlin and it could not cope with the m3 lump being strapped to it! It was borderline at higher speeds but
around town there was just not enough airflow through the rad to do its job properly, even with ducting round the rad and bonnet louvres added.
I ended up swapping it out for a bigger radiator sorted the problems out. This was on an S50B32 lump by the way
quote:
Originally posted by mcramsay
I used an uprated Ali polo rad in my m3 Marlin and it could not cope with the m3 lump being strapped to it! It was borderline at higher speeds but around town there was just not enough airflow through the rad to do its job properly, even with ducting round the rad and bonnet louvres added.
I ended up swapping it out for a bigger radiator sorted the problems out. This was on an S50B32 lump by the way
It was from coolex I believe it was a Granada radiator but a few bits custom made to my requirements. This was on a Marlin though which has no room
for a radiator so I had very limited choice of what was available off the shelf.
The m3 engine as standard uses a viscous fan, which I would have kept if I had the room, it would have probably have meant the polo type rad would
have worked.
If I remember my sums when working out the size I required for the rad the polo rad is has 55% less surface area than the stock radiator fitted to the
m3 production car.
I Cannot reccomend cool experts (coolex) enough they will make any radiator you want with the inlets and outlets any position you want and for a
really reasonable price!
quote:
Originally posted by craigdiver
quote:
Originally posted by rodgling
Rad connection looks good. I don't use an expansion bottle on mine (E36 M3 engine), don't have any issues with this arrangement - I end up with 5 cm of air at the top of the rad but it works and cools the engine just fine. It is a bigger rad than you've used though.
BTW I have a spare 11" fan (Spal) if you need one? (I switched to using a suction fan because of moving the oil cooler in front of the rad).
thanks rodgling, I think the polo rad will be borderline but car will not be pushed too hard, just for road use. I do have a fan that will be mounted behind radiator, just need to pick up some more flat bar to fabricate some mounts. once through sva I think i will look at an M3 upgrade.
cheers
craig
I thought the same as above about the radiator and being stuck in traffic however I was wrong, on idle there is very little heat input to the cooling
system, however at slower speeds with the engine under load is where the cooling system will struggle more as due to the low velocity of air through
the rad.
I only mention it out of experience and great expense .. 3 different radiators finally the last one worked. I also went down the Davies craig water
pump route... this doesn’t work on the s50b32 engine without major replumbing and modification of the stock thermostat which cannot be removed as
suggested by Davis craig... the cooling system needs it to be there.
In short the polo rad (especially the plastic one) is not man enough for the m3 engine unless you have 15” kenlowe fan on full pelt running at all
times. That’s the only way I could get it to not over heat.
my engine is the M52TUB25, hopefully should produce less heat than the M3 lump
One modification I would make to the above setup is to bring the intake forward so it sits in front of the radiator. On my car the filter is enclosed and the duct sits just next to the radiator. The theory is that when moving, it gets a good cold air feed, and when stationary, it generates some moving air over the radiator... probably doesn't help much but might as well.