Fan and Water Pump Testing

[GJCAT427]

Intresting test results Jay. I always heard the aluinium flex fans freed up HP over the yrs. Your results left me thinking.  By the way did no one catch Jays mule engine is running the dreaded FRAM filter! LOL

[machoneman]

Car Craft fan test results, a 13 year old article now. While one can draw some conclusions, I'd stick to Jay's more real-world results.

http://www.network54.com/Forum/215655/message/1066184641/Car+Craft+Cooling+Fan+Dyno+Test

[jayb]

Intresting test results Jay. I always heard the aluinium flex fans freed up HP over the yrs. Your results left me thinking.  By the way did no one catch Jays mule engine is running the dreaded FRAM filter! LOL

Actually, the "dreaded" Fram filter is the PH8A.  Those things are junk.  The Fram HP1 filters are actually pretty good.

[Heo]

Maby its not relevant for this test. But i
noticed when i lost a belt on a car if i drove
faster than 65 mph the fan actualy rotated
the waterpump enough to cool the engine.
Just a thought regarding acelerating the
dyno down the dragstrip.....
The speed helping with turn the fan but
the fan also causing aerodynamic drag
I gues someone have to do some realworld
fieldtest to realy figure out how to get that
last 0.?hp gain

[machoneman]

This is a tad off-topic but I believe it was Car Craft magazine that years ago also ran a test of a '72 or '74 (forget which) big block Chevy Chevelle at the dragstrip. The test only involved adding aero devices to the body to see if making it slicker would improve e.t. and mph. The car IIRC was a high 9 second racer and the tests (not all of which I can now remember!) were a whopping success and a hell of a lot cheaper for the $ spent than adding more hp. 

After some baseline runs, they added a under-the-front-bumper OEM type lower spoiler, then a really big front spoiler that almost touched the ground, then some belly pans under the seating area, a big sheetmetal  pan that covered the gas tank area right up to the edge of the back bumper, a top mounted rear deck lid spoiler, etc. Amazingly, IIRC the car did pickup 6-7 mph in speed, mainly due to the big front spoiler and the gas tank bellypan. Don't remember how much the e.t improved but there was improvement all be it not as much % decrease as the % mph gain.

Anyway, the moral of the story was do all one can to prevent air from getting under the front of the car and where one can't, make the bottom as smooth as possible.

Btw, this is NOT the CC article as it's not on-line but this HR article speaks of the same ideas.

http://www.hotrod.com/techarticles/body/hdrp_0609_aero_tricks_tips/viewall.html

[Joe M]

Interesting results.  I have to admit I was kind of skeptical about the Car Craft test because for years we were fed the idea than a clutch fan was trash and the flex fan was best.  That theory seemed to make sense if for no other reason that the flex fan was lighter.  Your numbers verify Car Craft's results.  Goes to show that the auto engineers knew what they were doing!  If they could have substituted a cheaper flex fan for the clutch fan, they would have.

[WerbyFord]

Hi Jay,
I gotta get over here more often, this is great stuff.
Do you recall the diameters of the crank pulley and waterpump pulley?

Also, I cant tell from the picture, Ford make some thick-blade fans (about same thickness as the basic 4-blade crossed fan) that would not flex, and some thin-blade fans that would flex, was your test the thick one?

[jayb]

Werby, where have you been?   As measured at the outside, the crank pulley diameter is 6.75", the water pump pulley diameter is 5.75", and the fan blade was one of the thick, non-flex ones.

[Boyes64]

   Thanks Jay... and yes I read your book - Excellent thank you!  As for the water pump/Fan issue, I think I'll stay with the stock unit with electric fans since I already have.  If I were heavy into drag racing, I'm sure I would go for the extra HP.  I'm mainly going to be cruising and hope to get some time down the strip later this year.

Something else to consider, I'm sure I would gain some ET just dropping about 50-75 lbs. off my fat X@# which would also help my health and easier on the bank account!

Anyways, thanks for the information!

Tim