Prep for Spal Fans?
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,242
Likes: 12
From: Kalispell MT
Prep for Spal Fans?
I've got my interior gutted and will be ready to start re-assembly within next 2 weeks. I will be replacing my original radiator during the winter also and plan to use a DeWitts with twin spals. Will I need to run a wire from the battery to the fans or do you tap into existing under hood wiring? If I need to run one from the battery, I want to make sure I get it done before putting in the carpet and dash. If it does run direct from the battery, what gauge wire do I need?
Thanks in advance!
Thanks in advance!
Former Vendor
Joined: Jan 2006
Posts: 698
Likes: 0
From: Social Circle Georgia
We do custom wiring when we install Spal fans onto C2/3s and typically grab off the starter. Depends on the year. What you can also do is buy one of the wiring kits that they sale. Comes with everything you need.
If you haven't ordered yet, our sale is going on until next weekend. DeWitt's products are apart of that sale.
If you haven't ordered yet, our sale is going on until next weekend. DeWitt's products are apart of that sale.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
DeWitts is the best out there......having said that, Tom has had his fill of PWM controllers for those Spal fans.....best to hook the 30 amp on/off relay heavy feed to the alt out stud directly....
and NO, i'm not getting into any of those/that discussion again with anyone....
it's where I put mine, and it's fine....my DVM says so....
and NO, i'm not getting into any of those/that discussion again with anyone....
it's where I put mine, and it's fine....my DVM says so....
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,242
Likes: 12
From: Kalispell MT
mrvette--please interpret:
"PVM" controllers ??
your "DVM" says ?? Doctor of Vertinary Medicine?
In any case it sounds like I don't need to add wiring thru the cockpit, I just need to grab voltage supply from a supply that is key actuated and can handle high (30) amps.
"PVM" controllers ??
your "DVM" says ?? Doctor of Vertinary Medicine?
In any case it sounds like I don't need to add wiring thru the cockpit, I just need to grab voltage supply from a supply that is key actuated and can handle high (30) amps.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
DVM - Digital Volt Meter. Everyone should have one.
Rick B.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
pWm, sorry,I mistyped.... Pulse Width Modulation....turns on and off the power to the fans, making a variable speed controller by essentially altering the ON time with the OFF time very rapidly they tend to be unreliable....and wiring them or any heavy constant load to the battery posts/starter cable is bad practice, as it upsets the charge the battery gets off the alternator when car is running, especially in traffic when loads are greatest on a hot day with a/c running....
Digital Volt Meter, more accurate for auto work than the old panel meter types.....been using one for decades now....highly recommended...sold at Lowes Depot....MY preferance is a Fluke meter....Fluke is the manufacturer for many other private label brands....
edit...your last comment there.....pull the power off chassis ground, same as engine really assuming you don't have other heavy wiring problems...under the pass engine mount to the frame,....
and the alt stud....the controll wire for the relay COIL goes to a switched hot, and the temp sensor keys the relay closing the main power 30 amp contacts.....
MY car is computer DPFI, so the computer tells the fans when to on/off....
Last edited by mrvette; Dec 30, 2007 at 10:29 PM.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,242
Likes: 12
From: Kalispell MT
Thanks for the interpretaions and further explanations. I should have figured out the DVM easily since I spent a lot of time with my Fluke this afternoon under the dash/console.
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Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
AHHH yes, upside down getting dizzy while you wish you could be dizzy from beer.....trying to read the meter while wraping yourself around the steering column.....welcome to auto electricals....
Navigator
Joined: Jan 2005
Posts: 9
Likes: 0
I installed a dual Spal fan set up into my 73 a year ago. The only problem I had was the relay for the wiring. I ended up wiring each fan with its own 30amp fuse and relay. The first setup melted internally and would turn the fans off when it warmed up. Really a pain to watch the gauge shoot up before I got home. What ever you do don't use cheap electrical parts and they will pull plenty of air.
Burning Brakes
Joined: Jan 2004
Posts: 1,043
Likes: 4
From: Va
DeWitts is the best out there......having said that, Tom has had his fill of PWM controllers for those Spal fans.....best to hook the 30 amp on/off relay heavy feed to the alt out stud directly....
and NO, i'm not getting into any of those/that discussion again with anyone....
it's where I put mine, and it's fine....my DVM says so....
and NO, i'm not getting into any of those/that discussion again with anyone....
it's where I put mine, and it's fine....my DVM says so....
