Electric Fans...Amps ???
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Electric Fans...Amps ??? (wheelsup)
Wheelsup,
knowing that your after every ounce of power in that car, I am making the connection with this that your worried about alternator draw to supply the fans with current.
I just wanted to mention what after a certain MPH ~30 the fans are shut off my the ECM, so it shouldn't effect anything to aweful much. Just be aware of the other stand alone coolant sensor that can kick the fans on, that I believe will override the ECMs control.
If your not inquiring about this for power, then carry on. :cheers: :thumbs:
knowing that your after every ounce of power in that car, I am making the connection with this that your worried about alternator draw to supply the fans with current.
I just wanted to mention what after a certain MPH ~30 the fans are shut off my the ECM, so it shouldn't effect anything to aweful much. Just be aware of the other stand alone coolant sensor that can kick the fans on, that I believe will override the ECMs control.
If your not inquiring about this for power, then carry on. :cheers: :thumbs:
Drifting
Joined: Mar 1999
Posts: 1,931
Likes: 1
From: Norcross GA
Re: Electric Fans...Amps ??? (ski_dwn_it)
I don't think the 91 has a "stand-alone" fan switch. If I recall correctly, only the ECM can control them.
As I recall the 91 has 2 smaller side by side fans. The 87 has one big fan that is controlled by the ECM. The fans are a DC motor, which means they have a high starting current. I think GM uses a 20 Amp fuse for these circuits. That is enough to get the fan moving and not pop the fuse. After the fans gets moving, these smaller fans should pull in the neighberhood of 10Amps.
as said, once you get some speed you won't need the fans, but don't get stuck in traffic w/o them. i.e. Staging lanes.
As I recall the 91 has 2 smaller side by side fans. The 87 has one big fan that is controlled by the ECM. The fans are a DC motor, which means they have a high starting current. I think GM uses a 20 Amp fuse for these circuits. That is enough to get the fan moving and not pop the fuse. After the fans gets moving, these smaller fans should pull in the neighberhood of 10Amps.
as said, once you get some speed you won't need the fans, but don't get stuck in traffic w/o them. i.e. Staging lanes.
Thread Starter
Melting Slicks
Joined: Feb 2000
Posts: 3,299
Likes: 0
From: Beltsville Maryland
Re: Electric Fans...Amps ??? (ZylaRace)
Jesse, what alternator? I had a few issues with it and I took it off. My car has the remote charging lugs and I charge the battery that way. The Optima battery that I'am using has a RC of ~90 amps. I would like to use the fans to cool the motor down to 120 between rounds. The fans seem to be a very draining accessory. I control each fan on its own switch. The ecm is no longer controlling my fans.
There is a very good tech article on sizing and calculating the RC values of a battery. Let me know , if anyone is interested and I will post the link.
Zylarace, is that 10a per fan. Thanks
There is a very good tech article on sizing and calculating the RC values of a battery. Let me know , if anyone is interested and I will post the link.
Zylarace, is that 10a per fan. Thanks
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Electric Fans...Amps ??? (wheelsup)
Wheelup,
Sorry. Just trying to put two and two together.
But let me ask, can't you just cool the car down, while its attached the the chargers? I'm not electrical guru, but perhaps this would cause the battery to not fully charge....NOt sure. :cheers:
Sorry. Just trying to put two and two together.
But let me ask, can't you just cool the car down, while its attached the the chargers? I'm not electrical guru, but perhaps this would cause the battery to not fully charge....NOt sure. :cheers:
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Drifting
Joined: Mar 1999
Posts: 1,931
Likes: 1
From: Norcross GA
Re: Electric Fans...Amps ??? (wheelsup)
Yes, per fan.
It has been a little while since I messed w/ fans, but 10A per fan should be safe.
10A-20A is a heavy draw, when compared to only running an Ign, Fpump, Inj, and ECM. Don't run the battery too low, or the first that will suffer will be the Fpump. Next will be spark. (An MSD will solve this one.) There are many variables here, but these 2 should be your weak points.
At low voltage, your fuel pressure will get lighter, and the inj's will open slower.
You really wanna go hog wild,... if you run heated O2's, disconnect the heater section. That will save you 1A-4A per sensor.
It has been a little while since I messed w/ fans, but 10A per fan should be safe.
10A-20A is a heavy draw, when compared to only running an Ign, Fpump, Inj, and ECM. Don't run the battery too low, or the first that will suffer will be the Fpump. Next will be spark. (An MSD will solve this one.) There are many variables here, but these 2 should be your weak points.
At low voltage, your fuel pressure will get lighter, and the inj's will open slower.
You really wanna go hog wild,... if you run heated O2's, disconnect the heater section. That will save you 1A-4A per sensor.
