E30 Zone

I have a C2 2.7 and wish to fit an electric fan, I understand aircon fan from an E34 will do the job. Trying to find out about electrical connections particulary temp sensor ie whether it'll need additional wiring or can just use existing sensor / connections. Anyone have a link to a comprehensive guide please - Thank you

This is generally considered a bad idea if not absolutely neccessary.

There is no wiring present, the temp sensor for the fan would fit in the side of the radiator, yours may or may not have the threaded hole blanked off for one, it would be on the drivers side about half way up.

Googling 'ken lowe electric fans' should get you on your way.

I've got instructions on wiring etc I'll send over if you want. I'll ping you a PM.

e301988325i wrote:This is generally considered a bad idea if not absolutely neccessary.

Why?

A viscous fan is simple and works well. Why complicate things if not absoluely neccessary?

Reason is to aid cooling and I thought electric fan would be more effective and reliable. Being a 2.7 it produces more heat and on last engine the head gasket went.

its a good idea on a tuned engine as the standard fan turning at engine speed may not be man enough to get rid of the heat.

i was under the impression the wiring and relay was present in the form of an aircon ellecy fan?

I would stick with the viscous setup to be honest

HairyScreech wrote: i was under the impression the wiring and relay was present in the form of an aircon ellecy fan?

Aircon fan relays etc have to be added to the fusebox, wiring isn't already there.

A 2.7 will produce no more heat than a normal M20 surely?? Alpinac227 is your viscous fan unit in full working order? if it's not replace that with a good one and see how you go. If you're still running hot then it sounds like there may be a bigger issue.

alpinac227 wrote:Reason is to aid cooling and I thought electric fan would be more effective and reliable. Being a 2.7 it produces more heat and on last engine the head gasket went.

Did the car overheat? The original cooling system in good working order will happily keep a 2.7 cool. A lot af HG problems are down to insuffficient antifreeze and/or poor quality antifreeze and also not allowing the car to warm up before thrashing it.

charlE30 wrote:

HairyScreech wrote: i was under the impression the wiring and relay was present in the form of an aircon ellecy fan?

Aircon fan relays etc have to be added to the fusebox, wiring isn't already there.

A 2.7 will produce no more heat than a normal M20 surely?? Alpinac227 is your viscous fan unit in full working order? if it's not replace that with a good one and see how you go. If you're still running hot then it sounds like there may be a bigger issue.

it should do, your burning more fuel in more air in a chamber of roughly the same size.

rule of thumb is equal heat (or 80% for some new super efficient engines) in Kw to the hp in Kw transferred to the cooling system.

its heat causing the expansion of gas that pushes the piston down, more power = more pressure = more heat.

if you want an engine rated at 7827777.7kw then you need to learn to dissipate the heat of a 22 megaton nuclear warhead every second.

it would theoretically have 74,840,000,000,000lb/ft of torque though. that would get the whole country diffin,

I have had no problems keeping my 2.7 cool with the standard setup,and no oil cooler....
I would suggest that your radiator is partly blocked,limiting coolant circulation.

alpinac227 wrote:Reason is to aid cooling and I thought electric fan would be more effective and reliable.

You have been misinformed on all counts!
An electric fan will provide more cooling at idle, which is why one is used on air con equipped cars, when the engine driven fan wouldn't shift enough air to cool the condenser properly. It would shift plenty enough for the radiator cooling though.

Thanks for all replies to date - Original engine blew Head Gasket (due to inattention to cooling..) then got lucky and got another (absolute corker) original C2 2.7i engine shipped over from Germany with 100,000 Kilometres so just 62500 Miles. Replaced all Cooling items Radiator, Thermostat, Water Pump, Hoses, Temp Sensors - Oil Cooler, Viscous Fan along with anything else at all that made sense whilst refitting engine, but recently blew Heater Matrix replaced this + Thermo again. Now replacing HG as precaution and want to fit elec fan. 212bhp 213Ib ft should mean more heat produced I'd have thought.

but still if cooling system is in good order it should be ok.
you can fit an electic fan.

drifters do it quite often with bms as the car is at angle to air flow, not getting good flow thru the rad often doing an indicated 60 mph in 3rd when only actually doing 20mph (if you know what i mean, spinning wheels etc. being a hero with tyre smoke!) hign revving with the engine under load.
mostly we fit a fan infront of the rad and leave the viscous undistrubed (to do its job under normal conditions.) the fan in front we generally fit blows thru to compliment the viscous with a switch on the dash to permantly switch it on an off as needed according to the temp guage. if its reading more than it does under normal use then it gets switched on.
the viscous uses next to no power from the engine tbh theres no noticeable power gain. cooling wise its important tho.
an overheating m20 can mean your not getting home from a drift practice day!

alpinac227 wrote: 212bhp 213Ib ft should mean more heat produced I'd have thought.

It does, but the fan, whether electric or mechanical, has very little involvement in getting rid of this heat. Apart from any time your car might be strapped to a dyno, when it's actually producing this power, it's likely to be travelling along at a considerable speed, and radiator cooling is performed by the forward motion of the car ramming air through the radiator. It could be argued than an electric fan in front of the radiator will actually reduce the cooling, since the fan hub will be shielding part of the radiator core!
If your 2.7 engine needs more cooling, it needs a larger or more efficient radiator (which in practice, in most cases, just means a NEW radiator), not a change of fan.