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cooling fan strong enough?


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First, thanks to all who have answered my other questions.  You've been very helpful.

 

Now, my quandry:  I have a 260Z into which is transplanted a 375 Hp/350 cid motor.  I've got a JTR radiator and an off-brand cooling fan about which I know nothing.  The fan draws 15 amps.  Do you think it will be sufficient for a street machine in Phoenix, or do I need to pull it and find a Taurus fan?

 

Thanks,

 

Jim

 

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Within the last year there was an extensive dicussion in a thread concerning radiator and fan choices.  Look for that thread.  BTW, fans are rated in Cubic Feet per Minute (CFM).  High CFM fans also draw higher amperage  which can be a problem for old electrical systems (melt down).  So you have to balance your choice of  radiator and fan combinations.

 

Suggest you do the following:

 

  - Search and read all threads dealing with radiator and fan choices. Become informed before choosing a radiator-fan set up.

 

  - Since you are in Arizona search the Arizona Z car website and check out the Z radiator. Check which fan is recommended for  that radiator.

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I've been reading specs on various fans. It seems that most 2500 cfm fans draw about 19 amps, so I would guess that the existing fan is 2000-2300 cfm. That might be enough since I don't have A/C.

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In addition to a fan shroud, you'll need to pay attention to sealing the front end of your car (i.e. the space between your front grill and the radiator).  This will ensure that all the air goes through your radiator.  Good luck with it.

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In addition to a fan shroud, you'll need to pay attention to sealing the front end of your car (i.e. the space between your front grill and the radiator).  This will ensure that all the air goes through your radiator.  Good luck with it.

 

Can you elaborate?

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Read this:

http://forums.hybridz.org/topic/56254-after-doing-some-reading-i-blocked-off-the-upper-grill-pics/

 

There's a bunch of info on this topic scattered throughout the various sub-forums.  Search on topics like "engine running hot" and "cooling problems" and you'll ferret out most of it.

 

Good luck and happy motoring.

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One of the challenges with cooling in a 240Z or 260Z is getting rid of the heat and air trapped inside the engine compartment (hood louvers or 280Z vented hoods can help).  The airflow into the engine compartment creates backpressure on the fan.  A fan with a 2500cfm rating is moving that air at zero back pressure.  As back pressure builds, the fan airflow drops off dramatically (check out some fan curves).  It takes a fan with a strong motor to keep good airflow (cfm) with backpressure created in the engine compartment, usually a fan with 20+ amps.  The Taurus fans can pull around 35 amps.

 

I am experiencing a similar problem on my two fan set-up. The fans aren't very strong and don't move enough air on hot days in stop and go traffic (they look good though).  I don't have a vented hood, so the engine compartment builds some backpressure and traps heat.  It is in traffic, traveling at low speed that the fans get the most workout.  At highway speeds, the air is being rammed through the radiator, so cooling system capacity is now the important factor.

 

My little fans were rated at around 8 amps, so they are not strong enough.  I am now looking for more powerful fans. 

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I was seeing 50A on my taurus fan when it was kicking on. I had to run two 30A fuses in parallel, with 10ga wire to compensate.  Just an FYI, it DOES suck some juice, but I've driven my car in 100+ degree heat, and DRIVEN it, not just putted around. I do have the radiator and fan well sealed, but lack any front end mods to channel air.

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  • 3 weeks later...

I just added an Edelbrock roots type supercharger and noticed that I gained about 20 degrees.  I am using a Griffin 26 X 19 radiator and Permacool 14 inch 2950 CFM fan with a 195 degree thermostate.  I am moving the puller fan to the lower left corner, adding a pusher 14 inch fan to upper right and changing the thermostat to a 180 degree. Hopefully this get things back to normal.  If so, I am going to put lighter and smaller 2200 7 inch permacool fan as a puller.  The JTR set back position made a big difference even for road racing.  I have louvers in both the hood and inspection panels.

Edited by Bowtiez
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  • 7 months later...

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