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Discussion Starter #1
Finishing the install of my 454 and had a question. I was curious if i should keep my electric fan and maybe add another or just delete the electric fan and slap a 17" mechanical fan on? I bought an OEM replacement BBC shroud but the mechanical fan i have is 19" and just a little too large to fit into the shroud.

The reason I ask is I had problems with my 396 always overheating. There was proper temperature drop across the radiator, timing was correct, tried under driven water pump, over driven, stock, Electric fans on the front of radiator pushing air through, moved to the back of radiator to pull air, switched out thermostats, no thermostat, restricted washer, straight water, 20/80 mix, 40/60 mix, when i went from a large 2 core to a smaller 3 core it helped. I never tried to switch to a mechanical fan and shroud.


I just dont want the same problems with this motor as i had with the last.
 

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Is your radiator copper/brass or aluminum? If it's copper brass, install a good aluminum radiator and use the electric fan as a puller and lose your worries:yes:
I went through the same thing with my 64 but it only had a small block. Bought an expensive 4 core double pass copper brass radiator from Chevy II only and it worked ok, but still wouldn't keep it cool. Switched to an aluminum unit from Be Cool and put in a 16" spal puller fan, and now it won't go over 185 unless i have the fan turned off. My fans on a thermostat and comes on at 185 and turns off at 170, even on a hot summer day it won't go over 180-185. The aluminum radiator made a huge difference. I definitely wouldn't use and engine driven fan. You need more air flow when the cars not moving and an engine driven fan won't do it, at least not without robbing power.
 

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Discussion Starter #3
Is your radiator copper/brass or aluminum? If it's copper brass, install a good aluminum radiator and use the electric fan as a puller and lose your worries:yes:
I went through the same thing with my 64 but it only had a small block. Bought an expensive 4 core double pass copper brass radiator from Chevy II only and it worked ok, but still wouldn't keep it cool. Switched to an aluminum unit from Be Cool and put in a 16" spal puller fan, and now it won't go over 185 unless i have the fan turned off. My fans on a thermostat and comes on at 185 and turns off at 170, even on a hot summer day it won't go over 180-185. The aluminum radiator made a huge difference. I definitely wouldn't use and engine driven fan. You need more air flow when the cars not moving and an engine driven fan won't do it, at least not without robbing power.
Both radiators are aluminum. The 3 core aluminum i plan on using is from Be Cool. Great radiator. Surprised it cooled so much better than the HUGE 2 core i have.
 

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when looking at radiators.. you have to do some simple math.... a typical copper/brass uses a 3/8" tube, some uses a 5/16" tube.. aluminums use any where for 1" to 1.25" tubes....

a 4 core 3/8" tube copper and brass 3/8" x 4 x 2 = 3" of cooling surface.. a typical 1" 2 core aluminum is 4" of surface tube.. per inch run
 

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I am in the middle of a V8 conversion (my 62)... and you guys got me thinking... I have a pretty much stock 283 and was planing on using just a stock V8 radiator thinking that they ran ok from GM that way. I was planning on a using a flex fan which pulls more air I am sure than a 4 blade stocker.

Opinions?
 

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flex fan would be ok and prolly work with the 283 with the v8 rad. Don't get me wrong, there's nothing wrong with engine driven fans, but since I converted mine to electric, I LOVE it. Cools so much better and freed up a little power, plus with the thermostat it seems I have more control over my temps. I converted my 64 over to a 350 and it's not a wild build, but certainly not mild either, and the copper/brass rad. just wouldn't do it. It worked but couldn't idle long in parades, cruise night, etc. Normal traffic was fine.
 

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The reason I ask is I had problems with my 396 always overheating. There was proper temperature drop across the radiator, timing was correct, tried under driven water pump, over driven, stock, Electric fans on the front of radiator pushing air through, moved to the back of radiator to pull air, switched out thermostats, no thermostat, restricted washer, straight water, 20/80 mix, 40/60 mix, when i went from a large 2 core to a smaller 3 core it helped. I never tried to switch to a mechanical fan and shroud.


I just dont want the same problems with this motor as i had with the last.
If you have a sufficient temp drop across the radiator, then changing the fan will not help. Is the pump moving enough water? Also where are you measuring your temp and how hot is it?
 

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I actually like mechanical fans. As long as they are clutch fans. Strictly mechanical fans (non-clutch) are a thing of the past for a good reason.

My setup has a very large griffin radiator, prolly one of the largest with a large flex-a-lite electric fan. No such thing as cooling issues here.

But I think with some of the electric fans out now you should invest in a decent fan controller. One thats not monitoring the temps well enough will rob you of engine power just as much as a straight mech fan due to the drain on the large alternator needed to run the fan.

I like a massive radiator and a decent electrical fan with a good controller. JR
 

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Discussion Starter #9 (Edited)
If you have a sufficient temp drop across the radiator, then changing the fan will not help. Is the pump moving enough water? Also where are you measuring your temp and how hot is it?
I switched out the high volume weiand water pump with a $36 autozone stock special. Thought maybe the water was moving TOO fast with the weiand. Honestly i tried everything with the 396.

Now that im thinking about it again 8 months later, I think my bypass hose was too small, i broke my fancy $60 polished flex bypass-hose and while i was waiting for a new one I replaced it with a longer, larger diameter rubber hose and the problem pretty much went away. If i was sitting at a light or left it idling too long, it would start to get warm but it would take MUCH longer for the temps to reach near 220* Once on the move again the temps would drop back to 195-205*
The reason i thought it was air flow was the minute I was driving again the temps would drop back down. After i put the fancy $60 bypass hose BACK on the pump/intake it went back to overheating.
I was putting my hood back on and sent some power surges with the ratchet grounding out on the horn relay, to the ignition module and pretty much fried it so when i would try and drive it to diagnose the problem it would heat up and then just stop working all together, pull over and wait for it to cool down for 15-20 minutes and it would fire back up.
While building my 454 i was researching the problem with Mallory thinking it was my Hyfire VII's ignition box and found out doing a google search that the ignition module will make your RPM's jump around on your tach (like mine was doing) and your car will just stop running until the module cools down. Then the car will fire up and run again until the module heats up again.

Well instead of spending 300 bux and more time diagnosing the problems i was having I sold the motor and spent $4,000 building a 454. *shrug* Am i messed up? Dont answer that!

I'm going to get an extra electric fan that pushes 3200cfm's and see what the two of the fans can do together.... Sorry for the long rant *Gets off soap box*
 

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A 2 core Be-cool will cool better than a custom 4 core brass/copper.
I make a dyno proven 630HP and 600TQ out of my small block, and the be-cool 2 core crossflow with twin 11" fans works great.
I also have vintage air II system, and the condenser is in front of the be-Cool rad. On hot days with the A/C on full the condenser in front of the rad gets so hot you cannot touch it with your hand, and it sits in FRONT of the be-cool rad. That additinal heat in front of the Be-cool rad could not possibly be controlled even with a custom 4 core brass/copper rad. I can idle in tarffic all day long and not overheat. On the highway I turn my fans off because the air speed alone keeps the engine at the set thermostat temp of 180.
I still have a small block rad support, and this year going to cut it to the size of the BB support. there is about 2" of the be-cool rad that is getting zero air because that Rad support covers that much of it.
The extra 2" x 18" deep area that i will cut out of the rad support will really help my cooling on 95 degree days.
Basically how the Be-cool 2 core rad works is witthout fans, and just using your mechanical engine fan the rad is rated to 350HP. Using the same 2 core rad and deleting the mechanical fan and adding a single 16" puller fan the rad becomes rated for 400HP.
Take the exact same rad and put on Be-cool's twin 11" rad fan system and it is then rated to cool 700HP.
take that same rad and add twin 16" fans, and that same rad is rated for 1,000 HP.
You can see its all air flow rated.
The rad I have is 29" wide x 19" tall., mechanical fan rated 350HP, one 16" electric rated to 400HP, twin 11" fans ( mine ) rated for 700HP, and twin 16" fans that same rad is rated for 1,000HP.
Be-cools ratings are real. I can beat, and beat and beat on that engine on a super hot day with the A/C on full, and the most I have gotten it too is 200.
beating hard on it usually no higher than 195. As soon as I get back into traffic, the fans will take the temp back right down to 180.

The width of the actual core,, less the side tanks is 24" x 17". As i mentioned i have the SB rad core support, and right now its hiding a full 2" of width of the core.
Once I cut out that 2" of rad support then the entire rad's core will be open to the air, I will never be able to get that motor past 195, never again, even beating on it on a hot day with the A/C running.
Needless to say I swear by Be-Cools cross flow 2 core rad, # 60184 its $499.00 with no fans and right now Jeggs is adding a gallon of be-kools antifreeze as a gift when purchasing the rad.
For fans you can use Be-Cools ************, or the Ford aerostar van's fan system, and it is rated more CFM's than Be-Kools twin 11" system. The Ford fan system comes as a 2 speed as well, and while at the wreckers take the relay system with the fans and shroud.
Mine I disconnest one fan in the spring and winter, and only use both fans in the summer.
it is CRITICAL that you use an aftermarket alum mecanical water pump, I use the Eddie Victor water pump.
There are a few members here that have followed my advise and still could not cool properly, and when i get a parts list, they are still trying to use a stock factory water pump. The victor pump will out flow a stock one massively at low RPM's where it is needed most, and will NOT cavitae at high speed.

Hope this helps.
 

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Factory clutch fan and shroud works for me.

Edit to add: I had overheating problems with mine running a flex fan and no shroud. The minute I installed a factory style clutch mechanical fan and shroud it went to 180 degrees (180 degrees therm) and has never moved higher. I'm running a 325hp 350 with the stock six cylinder radiator.
 

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unless you have a really high cfm fan , 4000 cfm or higher, the factory clutch fan is the way to go. super chevy did a article years ago , with different fans, electric worked the best when real high cfm above 4000. but when they came on they drew so much power the alternator had a huge drag on it , making the hp increase minimal if any, the flex fans were the worst fans on there test and the best was surprising the factory clutch unit. they only down fault found was the weight on the water pump shaft. it made the best coolant temps and had minimal hp drag.
a really good aluminum radiator and a early taurus fan set up works great, proven here.
a guy eddie i work with has a 396 in his camaro . it overheated and its basically stock. he had a cheapo electric fan on it, always overheated, he tried everything, then he finally went with the factory clutch set up and its cool as can be. never overheats anymore.
 

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I'm planning on running an electric fan soon. I was wondering what's better for a fan controller-temp probe in the intake, or temp probe in the radiator? I was thinking a 185 on/170 off. Would that be best with a 180 thermostat?
 

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I will never go back to an electric fan, too many things to go wrong. I've tried both now over the years and every time a mechanical with a stock shroud wins.

Nothing against them really, if you want to go to all that trouble to buy a big radiator, relays, wiring, switches and sensors as opposed to just using what has worked for many years its the builder's choice. Give me simplicity.
 

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I only use electric fans if there is no way to use a mechanical.

Mechanical fans are hard to beat for reliability and air flow.

I don't see any "coolness" factor or significant HP gain from going electric on my street machine that would make me want one.
 

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I run a 69 Camaro 4 core rad, all stock shroud and fan with a mild 396 with no overheating issues at all.:no: I wanted to keep it stock looking under the hood. My car is also 4 spd too.
 

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I will never go back to an electric fan, too many things to go wrong. I've tried both now over the years and every time a mechanical with a stock shroud wins.

Nothing against them really, if you want to go to all that trouble to buy a big radiator, relays, wiring, switches and sensors as opposed to just using what has worked for many years its the builder's choice. Give me simplicity.
I only use electric fans if there is no way to use a mechanical.

Mechanical fans are hard to beat for reliability and air flow.

I don't see any "coolness" factor or significant HP gain from going electric on my street machine that would make me want one.

yep... when it's all said and done... mechanical fans are almost 100% reliable... simple and effective,,,,, lots of changes to use a electric fan..... electric fans are a MPG ploy... the only electric fans I know of that are worth a hoot are the Taurus and MKVIII fans.... then you have to gage the amp draw HP loss in terms of load...:eek:
 

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I'm running a Ron Davis double pass aluminum radiator with dual Spal fans which are pulling just over 3,400cfm! These babies move a lot of air! My temps are (depending on the ambient temps.) 180 to 195. I am not running a by-pass hose from the manifold to the pump. It's a 2 core with 1" tubes. Coolant is distilled water with Water-Wetter.
 

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Discussion Starter #19
that is a beautiful set up.

Im getting ready to start my new motor up this weekend and just finished all my wiring. Was testing the fan and it wasnt coming on. If i cant get it working tonight i may be installing a mechanical fan and my shroud. Good thing i havent filled it up with fluids yet.
 

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I GOT AN ALUMINUM BE COOL RADIATOR WITH 2 SPAL ELECTRIC FANS AND I HAVEN'T HAD NO PROBLEMS IN MY UNCLES '69 CAMARO. WORKRD LIKE AS A CHARM FROM DAY ONE.:yes:
 
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