WestCoastShelby

Seriously I don't think anyone primarily (or always) driving on the street needs to worry about their fixed fan robbing power

Starfury

*shrug* It's a concern. The noise is what gets to me, though. I like to hear the exhaust, not the cooling fan.

barnett468

Yeah, i hear yeah, and clutch fans work fine on a stock car but as you likely know, if you install a thicker rad, it requires more air and in some cases, a clutch fan might not flow quite be enough especially in hot places like phoenix in summer etc.

also, they no longer make the correct length clutch anymore, so the newer ones might need shimming to keep the fan where it should be.

WestCoastShelby

I can get fixed fan blades 3/4" to 1" from the core without a problem where I find they pull air great. I've never been able to do that with a clutch fan. I also dislike shims on the generic clutch fans and the fact the new production models have slots instead of holes for the screws.

Mustangdemon67

do a quick radiator check by draining some fluid and looking inside the cap with a flashlight. check if the fins inside are clogged with debris. if they are, pull it and take it to a radiator shop and have the flush it. replacing the thermostat while your there is a good idea also. they have inline filters for radiators that are also pretty helpful for future driving. good luck

WestCoastShelby

Most radiator flushes can easily be done at home yourself without bringing the radiator to a shop to get hosed $$$. It is not rocket science.

Starfury

With a 1" and a 1/2" shim, iirc, the fan sits half in, half out of the shroud just like it should. I don't feel at all unsafe about the attachment; it's really not going anywhere.

With a 3-row copper/brass radiator, I have no cooling issues in 110F heat. If you need any more cooling power than that, you should be looking at a 2-row (1" tubes) aluminum radiator.

WestCoastShelby

You may like your fan there for your setup, however I need mine .75"-1" from my core since I use a high density 3-core with 6-blade fixed that will not pull air nearly as effeciently with the fan half-in half-out of the shroud (blades more than 1" from core).

barnett468

.
the reasons you do not have a prob may be because your engine is maybe only .030" over and maybe has no ac and the cylinders may not have been thinned by rusting over the last 45 years or so in the water jackets and it does not have a core shift and does not have 300 hp etc.

i have never seen a .040" engine with ac that would run cool at low speed or idle in 100 plus degree heat with a 3 row us made rad and clutch fan.

the aluminum 2 row rads are good but they are thicker than a 3 row so the need a bit more air flow than a 3 row.

if a car runs cool on the highway but runs hot at lower speeds, it is an air flow prob at low speed, not a rad size prob.

WestCoastShelby

+1 A lot of Mustang owners back in the day ran low amounts of anti-freeze in the summer, pulled thermostats, and other stuff that has been bad news for the cooling system chambers in the long run... No one likes to talk about how many 289s have rotted cooling systems.