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Cooling fan
https://slantsix.org/forum/viewtopic.php?t=61296		 Page 4 of 5
Author:  SlantSixDan [ Tue Jun 27, 2017 11:42 pm ]
Post subject: 
Quote:
What is their definition of:

Gross output
Maximum output
As-installed output

What is and what isn't hooked up?
Unfortunately, what you see is what I've got. The test was done by General Motors, and the closest it comes to that info is "per GM test protocol number such-and-such". It is a benchmarking test, not meant for publication; its intended audience would've either known that protocol by heart or had the reference book at their desks.

So it's incomplete, but I'll still take my chances with it as a source.
Author:  emsvitil [ Wed Jun 28, 2017 1:40 am ]
Post subject: 
Ok, then.......... I'll hazard a guess.....


Gross output 127 HP:

This was the old gross rating

https://en.wikipedia.org/wiki/Horsepowe ... ross_power

SAE gross power
Prior to the 1972 model year, American automakers rated and advertised their engines in brake horsepower, bhp, which was a version of brake horsepower called SAE gross horsepower because it was measured according to SAE standards (J245 and J1995) that call for a stock test engine without accessories (such as dynamo/alternator, radiator fan, water pump),[32] and sometimes fitted with long tube test headers in lieu of the OEM exhaust manifolds. The atmospheric correction standards for barometric pressure, humidity and temperature for testing were relatively idealistic.


As installed 104.5:

This was the old net rating

https://en.wikipedia.org/wiki/Horsepower#SAE_net_power

SAE net power
In the United States, the term bhp fell into disuse in 1971–1972, as automakers began to quote power in terms of SAE net horsepower in accord with SAE standard J1349. Like SAE gross and other brake horsepower protocols, SAE Net hp is measured at the engine's crankshaft, and so does not account for transmission losses. However, the SAE net power testing protocol calls for standard production-type belt-driven accessories, air cleaner, emission controls, exhaust system, and other power-consuming accessories. This produces ratings in closer alignment with the power produced by the engine as it is actually configured and sold.


Maximum output (just shy of detonation) 115.9

Net, but the AF ratios and timing curve were tweaked to give best results possible, not as spec'd/delivered.


Finally the 145 HP and 215 TQ were what was theoretically developed internally by the engine..... i.e. turn the engine over and see what the frictionally loss is at various rpms and ADD that to gross figures.
Author:  afastcuda1970 [ Wed Jun 28, 2017 4:59 am ]
Post subject: 
Quote:
Quote:
Wow, it's hard to imagine why all auto manufactures abandoned the fixed blade fan and have almost exclusively went to electric.
Is it really? Sorry to hear it. While you've got your thinking cap on about that, also think about this: a 22" high-lift lawnmower blade is a lot like a solid radiator fan, with the added drag of the grass it's dragged through. Oddly enough, a 4- to 5-horsepower engine is enough to swing that blade at 3600 rpm through the air and the grass at the same time, without guzzling a whole lot of gasoline in the process. Don't like that because it's a 2-blade fan instead of a 4- or 6-blade fan? Okeh, how 'bout the 3.5- to 4-horse engines commonly fitted to lawn vacuums with their 3- to 6-blade fans about 20" in diameter? Or look at the giant 30"-diameter 6-blade fans in hot air balloon inflators, powered by 7- to 8-horse engines.

Donno why you're so tightly married to your pet idea about engine fans, but I hope you two are happy together. :shrug:
Oh, now you are getting ridiculous. Lawnmower blades are heavy and flat, they don't pull much air and have a flywheel effect. Lawn vacuums spin in free air and don't pull air through a restriction like a radiator. Same for hot air balloon inflators. At least try to stay apples to apples.

Married to? I can watch a video of someone testing different cooling fans and measuring the results on a precise measuring device and understand the results. Pulling air through a restriction like a radiator takes much more power than a fan in free air. If you watched the video, you would have noticed than the engine gained hp by just removing the shroud.

I will stick with the results of the video until I see measured proof that it is wrong not just theories and apples to oranges comparisons.

You're welcome to used whatever fan you want on your car for whatever reason you want to. Myself and other's on this forum choose to modify our cars/trucks to increase efficiency. There is nothing wrong with keeping your car/truck original if you choose. :D :D :D
Author:  75valiant [ Wed Jun 28, 2017 5:44 am ]
Post subject: 
i would like an electric fan, simply to eliminate the danger of the unshrouded 4 blade steel fan in my 75. however, i won't do it until i first do the electrical upgrades, if at all. honestly, i like my stock car and vanilla ice cream.

(not that i can't get spicy, sometimes i just appreciate simple pleasures)
Author:  jcc [ Wed Jun 28, 2017 7:25 am ]
Post subject: 
Well you are on the right thread to pick an electric fan, just get the one that draws the least amperage, since that has the least drain on the alternator/engine, and disregard diameter, cfm, etc :D
Author:  SlantSixDan [ Fri Jun 30, 2017 12:10 pm ]
Post subject: 
Image
Author:  Reed [ Fri Jun 30, 2017 12:28 pm ]
Post subject: 
:lol: Icanhazhorzpowerz?
Author:  SlantSixDan [ Sat Feb 18, 2023 5:40 pm ]
Post subject:  Re: Cooling fan
Just in case if anyone's still interested in this topic, here's a relevant plot from the last page of a relevant report, namely:

Friction Tests of a Chrysler 1978, 225CID Engine

Report No. DOT-TSC-NHTSA-80-14
DOT-HS-805 487

U.S. Department of Transportation
Research and Special Programs Administration
Transportation Systems Center
Cambridge MA 02142

Available for free download here.
Attachment:
Screen Shot 2023-02-18 at 17.38.26.jpg
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Author:  ProCycle [ Sat Feb 18, 2023 6:08 pm ]
Post subject:  Re: Cooling fan
Wow. That's a significant power loss. Especially for a race car.
Author:  Dart270 [ Sun Feb 19, 2023 1:44 pm ]
Post subject:  Re: Cooling fan
Especially if you are turning 4500-6000 RPM for most of the track... Thanks for the post, Dan.

Lou
Author:  drgonzo [ Sun Feb 19, 2023 2:12 pm ]
Post subject:  Re: Cooling fan
The engine master video told me enough. I have the worst kind of fan now. I stand to gain hp
with almost any other fan. I see an electric fan in my future.
Author:  Greg Ondayko [ Sun Feb 19, 2023 5:31 pm ]
Post subject:  Re: Cooling fan
How does that compare to a model with a thermostatic fan clutch?
Author:  Rick Covalt [ Mon Feb 20, 2023 3:24 am ]
Post subject:  Re: Cooling fan
After installing my 3" radiator and electric fan in my race car, I would never hesitate to remove the mechanical fan on any of our engines. The engine is just so much easier to work on and safer on the fingers. Warm up time is shorter, and you only have a fan running when needed. Freeing up horsepower at 6300 rpm is a nice bonus too! :D
Author:  SlantSixDan [ Tue Feb 21, 2023 3:03 pm ]
Post subject:  Re: Cooling fan
Quote:
Wow. That's a significant power loss. Especially for a race car.
…only for a race car. Not for those of us driving on the street.
Author:  Dart270 [ Wed Feb 22, 2023 3:36 am ]
Post subject:  Re: Cooling fan
For normal street driving, this will have very little effect. Most people never see north of 2500 RPM (maybe 3000) in a stock Slant car.

Lou
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