In my car 740t i have the fan thatis conected to the water pump (stock) however volvo change that set up in the 940's and replace that fan with a electric fan. Is that worth doing? Is there any performance advantages by doing this? It also looks as though it's much easy to work on with out the big fan in the way.

The 940 fan has a low speed and high speed. There might be some complications wiring it to use both if you're not to good with car electronics. You'll probably want a automotive relay to take advantage of both speeds. Advantages will be much less noise and more power at higher RPM's. Another nice things about electric fans is that they can be on even when the engine is off. Only draw back really is that you either have to do it yourself or pay someone else to do it. I would think the fan would fit in pretty easily. The 900 and 700 series are basically the same cars. You will have to give up the mechanical have though.

I have been thinking about making this conversion myself. Just low on funds to buy the 940 fan. Also thought about doing a dual electric fan setup. Say two 12" fans side by side on the radiator mounted as pullers? One fan runs all the time and the other comes on at a certain coolant temp.
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1988 760Tic electric fan,boost gauge, remote start, MBC@10psi - 156,800 1966 M-B 230 sedan - 98,000 1982 Rx-7 - 201,000 Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us. -

The 940 electric primary cooling fan used on the 1992 and later cars will not fit the 1991 and earlier 700/900 cars. If installed behind the radiator it gives less than 1/4" clearance to the water pump pulley.

You can get the 1992 and later electric fan to work by changing the radiator, intercooler, induction tubing and hoses, and the support brackets for the radiator and intercooler. That makes it a boltt in job, but those parts are expensive even used.
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john

All I know is that others have been able to do it on mid 80's 700's. Don't know if they had any complications or trouble. I've also been thinking... like I said in the previous post... about a twin fan setup. Could make it myself or pull one from a Taurus, F-body or Toyota.
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1988 760Tic electric fan,boost gauge, remote start, MBC@10psi - 156,800 1966 M-B 230 sedan - 98,000 1982 Rx-7 - 201,000 Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us. -

Yes, electric fans are commomly installed, but the 940 electric fan is a large unit which will not fit correctly without changing the previously mentioned components.
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john

Advantages:

Lighter.
Quieter.
Less vibration.
A slight increase in power available to the rear wheels.
A slight improvement in mpg.

Disadvantages:

You gotta do it.
You gotta pay for it.
Maybe less cooling capability during heavy loads on a hot day with the AC on while going slow.
More current drain on battery and alternator (which consumes horsepower).

Years back I had a modified '75 245 (with the B20 pushrod engine). I removed the fan blades from the motor durin all but the hottest months. Because I traveled mostly on highways, I was rarely stuck in traffic. On those occassions when I was stuck, I simply turned on the heater full blast -- and cooled the engine while I roasted.

But that was maybe only 2-3 times during the summer, and usually only for a few minutes at a time.

Otherwise, the savings translated into the advantages I listed above, with an emphasis on a noticeable increase in power.
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Don Foster (near Cape Cod, MA)