sharkman76

I am adding electric fans to my new brass radiator to compliment my TPI upgrade. Thats when my research brought me to the Mark VIII VIDEO! Without question it kicks butt!

However to do that, a new cs144, fan controller,crazy relays,circut breakers, 8 gauge wiring, This sucks I just had my chrome SI rebuilt to 120 amps for the TPI! Are dual spals that questionable?

Is this Mark VIII fan the only electric that can cool our cars if they don't have a alum. radiator?

I want one and dont want one all at the same time!

We need further debate on this upgrade to make my head stop hurting.

PhotoVette1

Here are the reasons I went to the Mark VIII and DeWitts Al Radiator:

1. I had the Flex-A-Lite 210's installed several years ago with my 4-core brass/copper radiator. It cooled very marginally on hot days. With A/C on it barely made it. On mild/cool days there was no problem keeping coolant temps in line.

a. I have discovered through much research that electric fans are not recommended for 4-core radiators; the flow resistance through the thickness of the radiator cuts flow too much. You will notice that modern radiators mounted with electric fans are thin as can be; that is the reason.

b. The dual SPAL fans are far superior to the Flex-a-Lite 210's, but I wanted more.

2. When the 210's were installed. the advantages of the electric fans were obvious. There is great difference of opinion about this list, but on my '77, this is what I observed:

a. Fast warm-up.

b. Increased mpg. (3 mpg--and I keep careful track of it)

c. Smoother idle and cruise.

d. Faster smoother HiRev accelerating.

e. Makes working on the front of the engine a breeze (ptp) because of all the room it frees up over the original fan shroud.

3. The original thermal fan clutch was not designed for high rpm cruising--the thermal fan clutch disengages at 2650-2800 rpm--never to re-engage again until the car comes to an idle--no matter what the outflow air temperature of the radiator is. I would constantly run hot on the highway--most noticably with the A/C on.

a. My Turbo 350 transmission runs the engine at 3000 rpm at 70mph--the thermal fan clutch would never come on on the highway--temperatures would slowly creep up.

b. If I had an OD Transmission, this problem would not occur.

4. The Mark VIII RF64 is used on current Crown Vic police interceptors. If they can handle all those hours idling in donut shoppes throughout the country, my Vette will be able to too.

5. I have the DCControls controller. This is a pulse-width controller designed for the RF64. I also have a 75 amp Bosch relay (with manual switch) as emergency backup in case the controller fails.

6. I wanted a system that will cool my Vette effortlessly no matter what the conditions are and this is the best system I've been able to think of.

Well, I have thought of one better system, that is, using two inline counter-rotating RF64 fans--but I really don't want to run two alternators.


My system:

Edelbrock Victor Water Pump
Robert Shaw HiFlo 180F Thermostat
DeWitts Aluminum Radiator
RF64 Fan
DC Controls Pulse-Width Controller
Solid Lower Radiator Hose (I had the a/c belt cut through the rubber one once, so I elminated that possibility)

To answer your question, if you have a new c/b 3-core radiator with all seals in place and no a/c, then the dual SPALs is all you'll ever need.

Once you start going to the c/b 4-core with a/c--then the answer is maybe.

The RF64 is actually cheaper than the dual SPALs btw.

GDaina

You're joking, right? Dual Spals keep my 533 at 185 all day long. My rad is recored copper.

ESU

G,
I think you're one of the fortunate ones. Seems like two practically identical cars can have different cooling issues. If you've seen my thread on my cooling issues, who hasnt, you'll understand. The Mark 8 fan conversion really has me thinking. What photovette said about the newer fan clutches is right on the money. If I cant find one of the original AX marked clutches in the next few months then the mark 8 is the way I'm going and I'll be pestering photovette for a wiring diagram. I contemplated dual spals after a lenghty conversation with Tom Dewitt after the installation of one of his rads didnt help me. They were pricey when compared to the mark 8 and pulled a little over half the cfm of the lincoln fan. Although I do like the 2 fans as opposed to one, if the mark 8 craps out youre screwed, at least with the spals you'll have one left to buy you some time . The SPALs are nice if you have the money and your cooling issues arent currently extreme. I love reading about guys like you with monster motors and no cooling issues, makes me think there is hope afterall.
ESU

gkull

my dual spals work with my 383, but couldn't handle my 427 SB. The difference was Stewart Stage 3 on the 383 and Weiand Team "G" on the 427. I thought that it was the spals not putting out enough CFM. I would over heat at slow speed and high speed.


To the poster how many amps do the Mark 8's use? Spals are 30 amp

SIXFOOTER

I think I remember the Mark VIII peak was 107 and run was 38 amps.

PhotoVette1

Here's my wiring diagram. The black boxes with numbers are circuit breakers showing their trip amps. What I have done is to remove all the major steady state loads from having to pass through the existing fuse block then I beefed up the wire gage and connectors. Wire size is denoted by color as shown. I also eliminated the fusible links by using the circuit breakers.



I have mounted all wiring on the back of the engine compart. Here are the two '150' circuit breakers. It's still a work in progress...

0Tom@Dewitt

Stop the madness seems accurate to me. I watched the Video and that provided me with no information whatsoever. I looked around a little but I never found out what the CFM was. Apparently it must be a huge amount of flow with all those amp draws. Over 100a inrush and 38 a running. It just seems like one hell of big (unnecessary) load on your electrical systems and a limited surface coverage.

The guide lines for proper cooling is to have at least 2000 cfm and 70% core coverage. The dual spal provide 2780 and 80% coverage. No more air is required. 30a fuse only and each fan is about 15a running.

If the dual spals didn't work for anyone, then you simply didn't have enough radiator. The radiator is the only device that can remove heat. Fans move air, water pumps move water, radiators remove heat.

I think I even use the flexalite 210's before selecting this monster. Just in case anyone thinks I'm trying to increase sales with this feedback.

PhotoVette1

CFM is 5500 rated--I could use this fan as a driveway leaf blower no sweat...

The coverage area is greater than the 210's or SPALs. It sets inbetween the A-arms like God had intended it to go there.

The open area for airstream pass-through during fan idle is greater the 210's or SPALs.

By using the SPAL PWM controller or the DC Controls controller, run amps are kept to the absolute minimum.

The 210's--when attached to the radiator, put out as much air as a C3 a/c fan blower just about--I've had'em--they don't work with a c/b radiator and a/c.

I may be a fashion photographer now, but I used to be a nuclear engineer--I know an awful lot about heat flow & fluid transfer. That's also why I picked the DeWitts Aluminum Radiator.

0Tom@Dewitt

All I'm saying is you don't need that much air. I have a paint booth with a 24" exhaust duct that puts out 4000 cfm.

Bullshark

Listen to Tom If you still have over heating problems with the Dual Spal fans, the problem is not with airflow. I have had BB vettes since they were concieved and have dealt with all of there overheating problems one time or another. If you have to depend on that level of CFM airflow, you are probably covering up some other weakness in the system. Tom, I do disagree slightly with your statement that only radators remove heat. I'm sure you know that the air plays an important role in the system.....called convection.
As, most of you know, I run the RamJet 502 in my 70 coupe with the BeCool radiator and a Dual Spal fan setup without the fan speed control. ( Sorry Tom, I bought it before you really got your act together. If I had it to do over, I'd probably go with yours primarily because of the half azz fan mounting brackets on the BeCool). Personally, I really don't see the value of the fan speed control, unless you do have a fan that is way over specified like the Mark III. If your system is designed properly, the radiator and normal airflow due to car motion should do most of the work. The thermal time constant in our cooling systems isn't that short. Full on/off operation of one of my spal fans is just fine with the second fan used in extreme conditions with A/C. I just don't see the value ($) of the precise level of control that the pulsewidth controller provides unless there are some extreme conditions not typically seen.

PhotoVette1, don't get me wrong, I'm not flaming you, after all, I've always been a "Binford 2000" kind of guy myself But that Mark VIII fan just draws to much current for my blood.

Bullshark

PhotoVette1

I agree with that point for sure; but they are cheaper and last about forever--Ford product or no. And, fit better too.

You outta try one--I tried your radiator... A lot of people here would say they're overkill too. I just know they work. I'm just giving your higher capacity radiator all the air it wants.

I just want overkill for my cooling system. Last time my Vette overheated it was at the mall. My GF (me!) ended buying two more tops while I waited for it to cool off. Never again.

And another thing, the a/c system is a major heat load to the radiator. They are 1/2 ton systems so they put about out about 6000 btu. There's no place for that heat to go than through the radiator. The faster I draw air through the condenser coil, the lower the condenser coil out flow air temperature will be when it interacts with the radiator.

sharkman76

My car is a 4speed with alum heads and no AC new rad. new water pump so maybe I can get away with something less than that 100+ amp power pig mark Viii as impressive as it might be!

Other electric owners chime in please.
Anyone got recomended part numbers for the spals or something that works well? Tom are you there?

ps: Photovette1 your wiring upgrade rocks!

BerniesVette

I have a Mark VIII that only peaks 30 amps and draws 10 continous. Not a bad fan at all.
Bernie

sharkman76

That sounds like liveable numbers

Xakk

Dual Spal + relay kit.

http://www.dewitts.com/pages/product...asp?ProdID=251

vetteaddic

I just installed the Spals on my 427sb and they great

breathial

I have two 12-inch "Permacool" fans on a recored BB rad. The name brand should be "Perma-SUCK," they don't work worth a darn.

I already ordered the Mark-VIII fan from a guy on EBay (with great feedback), he includes the HD wiring and relays in his kit. I put in the minimum bid ($85, IIRC), and I was the only bidder! So, all told, with shipping puts me just over $100, total. When I get it in, I'll be sure to recoup some of my money by selling these TURKEY fans on EBay...

Right now, my 427 is quite mild- a lumpy cam, but other than that, quite tame. But with the two (cheapo) fans, temps would creep up... And I'm running a 5-speed, no AC! Anyway, my wife says I MUST put AC in, like a custom Vintage AC system, next spring... And later, when I bolt up another blower, I will definitely NEED the cooling capability...

Honestly, I don't care if I have to pony up for a 140-amp alternator, better than popping a head gasket...

I've learned the hard way- go with the biggest honkin' fan you can get... If it lowers the temp TOO much, that's what the thermostat is for...

ESU

sharkman76

Check out these Spals they are larger and more agressive than what I see here and other places. The cfm ratings look good too. Hight is the only concern but at less than 3/8th diff a little foam will fit the bill!!!!

http://cgi.ebay.com/ebaymotors/DUAL-...4309QQtcZphoto