[quote=73 ford guy;9787168]Your just banging off the upgrades on your old ford now hey!
whats next on the list
-New style 60/40 bench seat with center console
-Upgrade rear Driveshaft with all 1350 1 ton joints
-Headlight wiring upgrade
-Dual batterries
-Intermitent wipers
-Power windows


C'mon man you gotta have all that good stuff

Naw, I'm just about good now. Plenty of power to tow, 20 mpg, easy to drive, stops on a dime, over 1,100 mile range per fill up, I'm good to go.

Surprising Mark 111 fan info:

I came across some very interesting test data that led me to believe that the Mark VIII fans cfm is more wishful thinking than actual truth. Don't get me wrong the Mark VIII and Taurus fans have cured a lot of cooling ills at an affordable cost but the real cfm is actually under 3000 cfm. yep UNDER 3000 CFM actually 2700 on high and about 1700 on low. WHAT? no way!!!, Prove it. Read on.
Here is an actual CFM test between a Spal dual fan set up and a Mark VIII 2 speed and a few other fans. With actual amp draws at peak and start up. Tom Dewitt of Dewitts Corvette commissioned the tests back in 2007.

Test data
Your back and scratching your head. Me too, I had a Zirgo 3000 that was about the same rpm and 2 inches smaller blowing about the same as the Mark VIII on low. So I just assumed the Mark VIII was pushing about 3000 cfm. It is entirely possible that Zirgo tests theirs at 0.0 static pressure or not up against a radiator at all. The Mark VIII on high just moved a great deal more air than the Zirgo so again assuming it was about 4000 cfm. The test shows three things, the Spal dual is a good fan, the Mark VIII isn't anywhere near 4500 CFM some think it is and the Zirgo 3000 cfm isn't any where near 3000 more like 1700 under the same conditions as a Mark VIII.
That said the Mark VIII on low speed does cool my truck better than the Zirgo at its maximum speed and my real life road test does also prove the fan is a good affordable cooling solution.

 

Hmmm...

I use a 60 amp fusible link for HIGH speed, however...

The Mark VIII fan instantly will blow a 40 amp Bosch relay.

It will also take out a Ford style starter solenoid within minutes, and a Ford glow plug relay in about 10 minutes.

Those experiences are ENGINE-ON or running. I have found the fan behaves drastically different when powering it ENGINE-OFF versus ENGINE-ON and it is seeing 14+ volts rather than something around 12. The 40 amp Bosch works fine until you start the engine and click on the fan, it's fried instantly.

So, I am going to assume they are taking their amperage readings with engine off or just straight off the battery for their tests.

It's no secret guys are using high amp continuous duty relays for high speed or piggy-backing bosch relays in order for the fan to operate. I had extra parts lying around so I tried what I had before getting the continuous duty relay.

Josh

 

I call BS, mostly their low speed shows about 2500 in low speed and 2700 on High? There is a HUGE difference in how much air each setting produces. Not a measely 200 CFM, but darn near double.

I would gladly tout a 2500 CFM low and maybe 4000 for high, but the difference is remarkable.

Again, was that test using running voltage or straight battery? The difference here as well is extremely noticeable.

But whatever...

Josh

 

There's so much info on the net. I read somewhere that the M111 is the highest cfm fan ever made, period. If it cools a bb on the low setting, or a sb towing a major trailor on low, you know it is moving huge air.

What cracked me up was in one of those write ups the guy said that with his 350 sbc and the m111, he could watch the temp gauge drop after 30 seconds! That's it in a nut shell.

 

I can't believe that ppl dont like twin thermo fans. Ive never had a problem since I installed them on my 79. The old straight blade thermos were useless but the curved blades really move some air, and you can get them set up to run 2 speeds!

 

I don't think people dislike them. But when the Taurus and Mk v111 fans are readily available, and can be had a any j.yard for $15--40 with shroud, and they kick but on any aftermarket fan ever made, why would anyone choose differently?

 

ignorance is bliss...

I've always pushed stock type fans of flex-a-lite & similar BS. It wasn't until somewhat recently that people started believing me. Maybe the trend of the Taurus/Mark VIII fan had something to do with it???

 

I've been reading all the sites, and trying to understand how to wire the T. fan to two separate thermo controls. I read that the both h&l speeds should never have power at the same time. I guess I'll have to run each through a switch in cab.

 

That's the point, some guy shells out $400+ for a crappy aftermarket fan that doesn't work worth a damn and then gets pissed when someone posts on a forum that a $14 Mark8 fan works better than great.

Josh

 

I can somewhat mirror the SBC claim.

I was getting ready to do a minor tune-up so I figured WTH and let the engine warm-up in the driveway without the fan. So I let it peak at 230 degrees idling, 90+ outside temps and then hit HIGH speed. It easily brought the temps back down to 200 in a matter of a minute or 2.

It wasn't long and certainly not 30 seconds quick (I bet other areas of his life are probably that quick) but definately not 5-10+ minutes of the fan running to bring the engine temp down.

Josh

 

I'm looking the least expensive controller for these fans run $80. I'm going to pay about $15 for the fan, and $80 for the controller?

So I figure I'll just pull the oem 50 amp Taurus fuse, and a couple of T. relays while I'm at it. I also found a dual stage thermo switch which sits in an audi/vw radiator. I thought I could use the autometer sending unit housing, which sits in the rad. hose, and that way do away with the thru rad. sensor. The problem? The sending unit housing alone is $40.

Heck, maybe I'll just stay with the sensors I have! and save some scratch. Just thought it would be really clean with the dual stage.

 

You tee into the input heater hose to run a secondary sensor. All that would be needed is a ground wire to run to the tee fitting since before and after it would be the rubber hose.

Josh

 

The Jeep guys use the Taurus fans, newer cars have two fans. Link on some good wiring wrte ups in this one. Contour Fan. Factory speed control? - JeepForum.com

 

What relays are yall running? And what is a decent temp. on/off switch?

 

Yeah, that's a good question. If you ask ten guys you'll get ten different answers regarding the relays. I'm getting ready to do mine, and I think I'm going to pull my relays from j/y Taurus, and string two together. If you google Taurus fan install, you'll find loads of ideas. I like the idea of being able to string together a nice system for just a few bucks!

I have an adjustable thermostatic control now, and I set it at about 190. That way with my 180 thermostat, I can cruise w/o the fan coming on.