installed brand new thermal clutch fan for a 90 Caprice onto the camaro, with NO shroud by the way, and the car now runs at about 190 on a cool day and 215 on a hot traffic drive as opposed to 210 on a cool day and 235 in traffic with electric fan, so there you have it, mechanical fan is worth 20 degrees!! As for HP, i didn't notice any loss, however the mechanical fan is much scarier to have in the engine bay because its like a giant blade waiting to shred something up. According to Car craft, the difference between a top of the line electric fan and a regular $60 clutch fan was only 4HP. I'm going to have to say its worth it.

 

with my dual electric fans, my temp never goes over about 200. did u have single electric before??

 

A fan with out a shroud is worthless, stick with the electric fans, way better and no hp loss.

 

You don't think the alternator requires HP under heavy load? I have a hard time believing that he found a fan to fit, my 89 iroc I looked at and there is very little space for a mechanical fan, the MAF sit's pretty low. Believe me guy's, if I could put a clutched fan in place of the electric I would do it in a heartbeat. Not to mention especially if you have dual fans your alternator will last twice as long.

 

NOT TO MENTION A CLUTCH FAN IS CHEAPER TO RUN I THINK,NO RELAYS TO WORRY ABOUT,HOT WIRES,STRAIN ON THE ALTERNATOR..FANS THEMSELVES BURNING OUT AND THE WATER TEMP IS MORE OR LESS AT A CONSTANT TEMP.VERSUS AN ELECTRIC FAN THEY KICK IN WHEN THE TEMP GOES UP SO THE TEMP GOES UP AND DOWN AT A BIGGER RANGE....SO WHERE CAN WE GET A CLUTCH FAN FOR GTA WITH A SHROUD ANYONE..CAPRICE LIKE THE OTHER GUY SAID?

 

Get ready for water pump bearing death and seal failers LOL, I'll stick with the electrics, because you get MAX fan rpm no matter if your at idle or driving. PLUS THE ONE BIG THING is, the more heat you pull through the less compression work needed by your compressor THUS LONGER COMPRESSOR LIFE. HP drain is much less with the electric fans, YOUR FORGETTING GUYS run electric water pumps too LOL so there has to be a benifit on the drag strip vs mechanical.

 

You guys are kinda missing the point. I was mainly saying that swapping to a mechanical helped my overheating problem the quickest, painless way possible, where-as with the electric fan, it overheated, plain and simple. And in the perfect world I'd love to have a dual fan setup, but who wants to donate me $150-200 so I can go buy one because in 110 degree Tucson Az dual fans go TOP DOLLAR if you can even find them. And believe me, running below 220 in ****ty-*** tucson traffic on Speedway sitting at the Swan light at 5'o clock friday afternoon on a 109 degree day is quite amazing in my book. Here's another update, took out the AC condenser yesterday................today the car runs at 190 in heavy traffic, 160 at cruise!!!! FWUCKING SWEET!


For everyone that says a clutch fan robs so much power, you need to go read that Car craft where they test the $200 Flexilite electric versus a $65 clutch fan, it was honestly only like 4 HP. That would NOT make any NOTICABLE difference at the track. How's about this for irony: Since I only spent $30 on a slightly used clutch fan (with a new clutch tho) I had some extra money left over and I bought a 3.73 posi rearend off a friend for $50, and trust me, with 3.73's posi and a clutch fan, the car is WAAAY faster than it was before with a peg leg 3.42 and a non-HP robbing electric fan! Think of it in HP per dollar terms and it all makes sense.

And yes they do make a clutch fan to fit thirdgens including GTA's. Go out and buy one for a 1990 Caprice with a 350TBI motor. If you don't believe me I'll go outside and take pictures. I KNOW it will fit just about any thirdgen car because on our camaro we even have a super fat griffin aluminum radiator, which means on a normal radiator you'd have WAY more space up front for a clutch fan.

 

really I think its all a matter of preference. i know on my 355 i like the electric fans just so nobody checkin out my car will sever a limb or two. its all a matter of what one believes but from personal experiences ive had heater hoses wiggle around on the water pump and slap into the clutch fan talk about a mess and a half.

 

Some of the early 3rd gens v-8 cars came with clutch fans from the factory so you should be able to find a shroud to fit.

 

i think eletric fans are much safer, but need work sometimes to make them work right.. dual fans cool down and work very nice..

 

I must be doing something wrong, because my car never goes over 195, even in 100* + weather, even if I flog the **** out of it.. I only have a single fan too. It did climb to 220 when my air dam was missing.

 

i think all the old car guys prefer mechanical fans.. while us younger guys prefer electric (well thats the way it is with the guys i know personaly)

 

16-17 inch fan and clutch for a small block chevy and a shroud from an early third-gen is all you need. I've been running a flex fan and an early third-gen shroud I got new from the local GM dealer for 9 years. Same old water pump that was on the car back then is still working just fine. Never had an overheat problem since then(100+ in town with the A/C going). I figure why mess with something that works. Electric fans really got popular in FWD cars that had the engine sideways(couldn't use mechanical), so maybe the older folk see the electric fans and it reminds them of those cars. Or could it be old technology that is still dependable.

 

I think the real reason for all the discussion is that there were problems with the TG electric fan reliability. Most of that came from lousy relays and poor quality connectors. The newer version relay is far more dependable and should eliminate most electrical problems. One definite advantage to a clutched fan is operating temp stability. GM by design had to have a 20 degree or so swing before turning on the fan because the engineers knew the large electrical load the fan(s) created. Fact is that the dual fan setup will move more air faster than a clutched unit. Realistically I think both work well but with a TPI motor the electric fan is probably the more efficient way of cooling the engine faster.

 

Means GM new there sh*ty altnators would fail before warrenty.

 

I generally know where you come from with reference to GM in general. Fact is that Delco electronics components are recognized as some of the best quality in the industry as demonstrated by thier widespread use by many different manufacturers including Jaguar. Any modern vehicle loaded with power accessories generates a huge demand of the alternator. The problem is compounded when people try to re-engineer without the benefit of knowing why it was designed that way originally. You can retrofit any alt you want on a TG and if you modify the fan cycling the way some people here do you will effectively cut it's service life in half. The warranty thing you refer to makes no sense at all. You can bet that if they had a major warranty issue with the CS series units they would have redesigned it. Last thing ANY manufacturer wants to do is pay out a boatload of money for warranty claims.

 

Well Danno you probley had better luck then I have, my first altnator the rear bearing turned into a fire siren at 45,000, my IAC fell apart in my hands it was so bad at 50,000. Lets not get started on the TPS, those are like candy to my car. I think everybody's tune is based on their experience.

As far as "re-engineer" it's BS to run a car with a fan temp turn on at 235. 220 is perfect combustin temp on an engine so the emissions excuse is BS. Thats why Hypertech and other people change theres to a reasonable time like 200 or lower if your using a 180 thermostat.


Thanks for stating my point, make the fan run ONLY when really HAS to so that the marginal altanator makes it past 3year/60,000 warrenty then the manufacterur doesn't have to cover it.

All I have is A/C and the stock radio. My 2nd Altanator was an AC DELCO remanufacture and it only lasted a year.

The altanator is size ok at 105 amps but the parts in side don't last long probley due to heat regardless of load. I have the 195 temp switch, runs at some red lights thats it. I don't think that should:

 

Ryan, you are either the unluckiest person in the world or your car is possessed by demons. I have an 89 with a 5.7. With the exception of the fan relays which I admit had an engineering defect everything with the exception of the O2 sensor is original. And in fact the O2 never failed I just changed it based on time. I have the original alt which I rebuilt just this past summer. I don't care what brand car it is depending on driving habits you can pretty much figure on replacing the alt every 40k or so. A big problem with the CS unit was heat from the rectifier block heating and drying the rear bearing. All the newer alt's have been downsized physically and tend to run hotter that's just the way they all build them today. A rear bearing cost's around $4 at any mechanical supply house. Very seldom does anything electrical fail with the exception of normal brush wear. My primary fan comes on at 222 degrees which is stock. On the 6cyl version I guess they could make it a little higher. 235 is nowhere near a problem for fan turn on on a pressurized system. I know I won't change your mind but I will tell you this, if you think hypertech or any aftermarket company knows more than the design engineers you are only kidding yourself. Everything they do has a reason behind it.

 

Actually, the emissions related 226* fan turn on story is not totally BS. It was for emissions, but in a round-a-bout way. GM turns the fans on late to raise the engine temp in an attempt to burn off carbon deposits left on the pistons by people who don't ever use more than 1/4 throttle. If left unchecked, these deposits would build up to a point raising NOx emissions output past an acceptible level and eventually leading to constant off-idle detonation. (if you have any question about this theory, drive your grandma's car and see; obviously results will very).

As for: does the clutch fan really work better, a simple answer would be: yes, at above idle speeds, if it is a good one. The problem is, a mechanical fan is most efficient when used with a 360* shroud. Without a shroud, the fan can recirculate engine compartment air. Many of you are probably experiencing electrical fan problems because the stock electric fans commonly found in 3rd gen F-bodies don't turn on until 226 via the fan switch and/or stock computer and they also don't have shrouds and can produce some of the effects I stated earlier.

A shrouded fan (be it mechanical or electrical) has no choice but to pull air thru the radiator. There is simply just no where else it can come thru because of the shroud.

This brings us to my next point. A mechanical fan, be it clutched, non-clutched, or flex, is not very effective unless you are off idle or above about 1500 rpm give or take your pulley sizes. Furthermore, above a certain rpm (about 2800) you don't need to spin the fan any faster hence the reason for the clutch. Still, given all this, there is still more rotating mass (with a mech fan) which will affect more than measurable HP and TQ, it will also affect RPM rate of climb, which most dynos will not report. This number does have an effect on 1/4 performance (although it is not a big one). All that being said, the mechanical unit will cost you power thruout the RPM range regardless of vehicle speed. You still have to turn it even if air is coming thru the radiator by itself.

So which is better? Well, an electric fan will pull out some HP too, but it does it through the alternator. The difference here is that when your alternator is above 2000 engine rpm, it is already past the point where the max load is on the engine. The higher the RPM of the engine, the lower duty cycle the alternator has to operate at to maintain voltage because of the magnetic principals involved. (i.e. greater speed of passing magnetic flux lines will produce higher charging current which means load or resistance of the rotor spinning will go down) You have to have an alternator anyway, why add a mech fan which will sap even more power. Besides, a properly operating electric fan system will most likely shut off at highway speeds (and higher speeds going down the track) which will terminate the load to the charging system. (again, here you will still be turning the mech fan, even with a clutch)

As an overview, the least power-robbing, best performing cooling fan(s) would probably be a dual setup mounted to a shroud. Unfortuneatly, the aftermarket really doesn't have any units that come close to the effectiveness of a dual LT1 setup or even it's smaller cousin from the '99-up malibu's.

-Mechanical fans don't work as well at idle speeds.

-Electric Fans work at 100% speed at any engine speed (as long as the alternator can keep the charging voltage up)

-Shrouded mechanical fans will pull more air thru the radiator than electrical units but only above idle speeds (in most cases) and will cost you power and gas mileage, period; with or without clutches.

 

Well here i the factory manual for the 1992 v6 it says 240 fan turn on temp. I'm sorry guys but COOKING an engine is BAD any way you look at it. Once your at thermostat stock temp what difference does it make if you maintain about that temp????

I never said anybody new anything more then GM but your forgetting what hapens to a car after they get done engineering it.

THE BEAN counters get a hold on it and say cut costs!!

LOL