[Formulajones]

We just race our street cars right off the street with working clutch fans and alternators, half the time don't even open the hood. Easy Peasy

Shucks last time at the track dad had a starter issue and just left the darn thing running in the staging lanes

[slowbird]

Originally Posted by Formulajones

We just race our street cars right off the street with working clutch fans and alternators, half the time don't even open the hood. Easy Peasy

Shucks last time at the track dad had a starter issue and just left the darn thing running in the staging lanes

That's what we do with our street cars also. But always looking for more, lol

[Formulajones]

Originally Posted by slowbird

That's what we do with our street cars also. But always looking for more, lol

Agree, we're hotrodders, that's what we do

[NeighborsComplaint]

It was once popular to run a tiny import car alternator both for weight and parasitic drag reduction.

[mchell]

I’ve played with cutting out the alternator field via a switch. Yes, it did yield a slight improvement at the track. Mine was .02-.03 reduction in et best I could tell…

Problem I had was my fuel pump would slow down a bit with the reduced voltage. At times this would prove detrimental. IF the fuel pump kept me in fuel, cutting the field reduced my et slightly.

Removing the power steering pump belt generally gives me an easy .05 or more…. Both mods get me close to a .10 in et reduction as I recall.

[Half-Inch Stud]

In reality, the Alternator is drawing < 1 hp at cruise. 1/4 mile acceleration would be a few HP lost.

Nobody 1/4 miles with a dea battery, Hi-beams, and a 30 Amp electric fan all running.

My electric fan only goes on when i turn it on: really long traffic lights, jams, and after the 1/4 mile run.

[AG]

Originally Posted by Half-Inch Stud

In reality, the Alternator is drawing < 1 hp at cruise. 1/4 mile acceleration would be a few HP lost.

Nobody 1/4 miles with a dea battery, Hi-beams, and a 30 Amp electric fan all running.

My electric fan only goes on when i turn it on: really long traffic lights, jams, and after the 1/4 mile run.

I'm pulling 65 amps down the track with an electric fan, water pump, fuel pump and MSD box. Most of it is the Mark VII fan pulling 44 amps.

[Tom Vaught]

Agree the Mark VII uses a bunch of amps to drive that electric fan.
At one time that was a very good fan for a engine pulling a trailer and race car.

Depends on what your application is, simple really.

Tom V.

[Half-Inch Stud]

Craaap. My elec fan is in the 15-20 A catagory, a GM upullit deal. Sold my identical spare.

May be putting the flex fan back on some day.

[Formulabruce]

Originally Posted by Half-Inch Stud

Craaap. My elec fan is in the 15-20 A catagory, a GM upullit deal. Sold my identical spare.

May be putting the flex fan back on some day.

Factory clutch fan has been found to have the least drag and least affect on horsepower. If that enginemasters video IS the full edition, it shows this at the end, much to the dismay of Jeggs, Summit, etc...
The Final test on the engine masters video WAS the factory clutch fan and shroud. This was edited OUT of the video. Why? because it used the LEAST power, and because it really puts a damper on aftermarket "sponsors" of motor trend.
Its sad this classic info is missing, it was a huge shocker to them...

[PAUL K]

Interesting thread. My guess is 95% of street cars would find more power in a better camshaft design than the least efficient designed alternator would take away power wise.

[Formulajones]

Originally Posted by Formulabruce

Factory clutch fan has been found to have the least drag and least affect on horsepower. If that enginemasters video IS the full edition, it shows this at the end, much to the dismay of Jeggs, Summit, etc...
The Final test on the engine masters video WAS the factory clutch fan and shroud. This was edited OUT of the video. Why? because it used the LEAST power, and because it really puts a damper on aftermarket "sponsors" of motor trend.
Its sad this classic info is missing, it was a huge shocker to them...

Yep, long before there was engine masters I recall a certain magazine that did a fan shootout article. May have been Car Craft. I've even posted that info with a link to the actual article on this forum in the past.

The only thing that beat the clutch fan setup, was no engine driven fan at all.

[Half-Inch Stud]

Originally Posted by Formulabruce

Factory clutch fan has been found to have the least drag and least affect on horsepower......enginemasters video....full edition...

I'm 0-for3 on the Mech clutch fan surviving my enthusiastic Street driving with TH-400 shifting.

Got 1-better, the best: neighbor has an electric-clutch Mech Cooling Fan. International farm equip? Electrical Clutch for Mech Cooling Fan been outside sitting on the Ground, i picked it up and recognize it would be fantastic.

Clutched-Alternator sounds excessive, unless normally engaged without power, Powered dis-engage.

[Formulajones]

What are you doing to mechanical clutch fans that you're 0 for 3 with enthusiastic driving??

They've been in use since the beginning of time on some of the most high strung, high rpm engines the big 3 have produced throughout the muscle car era.

Can't tell you how many times over decades of use I've spun them to 6000 or 7000 rpm without a single problem on numerous cars. May have even missed a gear in there once in a while over the years and zinged it pretty good

[Formulabruce]

There MUST be some merit to the question. My Wifes 2020 Nissan Daily driver has a small, but powerful alternator ( around 100a)
This small alternator has a CLUTCH inside it, similar to a clutch on a AC pump... You cant see it. I would have never known except the belt would flutter
and make noise, so the whole $500.00 alternator got swapped under warranty.
I am betting Other brands have gone to this for fuel economy reasons... so it IS worth discussing..
There ARE reasons you will NEVER see a alternator on a EV....