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Will a 17" w/6 Blades, Standard rotation Fan work on my stock 350 engine I'm having to replace the fan?
 

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youve asked a question without providing a 10th of the related useful info
first the fan has a CFM (CUBIC FEET PER MINUTE) (2500 cfm and up is generally a decent start point for a performance engine,and an AMP rating (ELECTRICAL CURRENT requirement ) generally this falls in the 40-50 amp range (peak draw)on a performance engine with a single electric fan which your cars electrical system may or may not be able to fully supply, if the alternator is not able to fully supply the fan motor electrical draw, it will not provide the required air flow.
fans generally require a matching fan shroud placed and correctly clearanced on the rear of the radiator to reach the full cooling efficiency, your radiator will generally require about 1.4 square inches of surface area per cubic inch of displacement. your engines water pump must be able to provide the required coolant flow and the t-stat must also not restrict coolant flow rates.
ignition timing effects the engine combustion and exhaust gas temperatures, so thats important.
keep in mind almost all the engines heat is generated in the upper 2" odf the cylinders, combustion chamber and by heat generated in the valve train and rotating assembly, thus OIL FLOW rates are also critical as its OIL flowing over the engines moving components that absorbs and transfers at least 70% of the engines higher temps to the block and coolant, thus adding an oil cooler with a fan to also transfer heat absorbed by that mass of oil will further reduce the heat load on the engine coolant!
with an auto transmission, the heat load the radiator deals with is further compromised by the transmission fluid heat transfer, so adding a trans fluid cooler with an auxiliary fan will again reduce the engines cooling system heat loads.

http://garage.grumpysperformance.com/index.php?threads/thoughts-on-cooling.149/

http://garage.grumpysperformance.com/index.php?threads/how-the-cooling-system-works-basics.853/

http://garage.grumpysperformance.com/index.php?threads/how-to-choose-an-electric-fan-in-4-easy-steps.7774/

http://garage.grumpysperformance.com/index.php?threads/do-i-need-the-fan-shroud.13847/

http://garage.grumpysperformance.com/index.php?threads/auto-cooling-system-flow-rates-and-heat-transfer.9880/

http://garage.grumpysperformance.com/index.php?threads/setting-up-electric-fans-correctly.7150/

http://garage.grumpysperformance.com/index.php?threads/unwanted-engine-bay-heat.12186/#post-59072

http://garage.grumpysperformance.com/index.php?threads/transmission-and-oil-cooler-increases-durability.176/#post-48374
 
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I forget the year of your Corvette Tex Vette.
The larger the diameter fan you can fit in the better.
The 19 inch diameter mechanical fans many favor.
About 99 % of the Pontiac TA guys use Clutch mechanical fans with A/C.

I like the Flex A Lite #398 Syclone Fan.
2500+ cfm.
I installed one my 87 Corvette .
Gets the job done.
On my 63 Pontiac A Syclone fan also.
Made in the USA Also .

Mechanical Fans you want to stick With Flex A Lite if not original GM .
 

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Discussion Starter #4
youve asked a question without providing a 10th of the related useful info
first the fan has a CFM (CUBIC FEET PER MINUTE) (2500 cfm and up is generally a decent start point for a performance engine,and an AMP rating (ELECTRICAL CURRENT requirement ) generally this falls in the 40-50 amp range (peak draw)on a performance engine with a single electric fan which your cars electrical system may or may not be able to fully supply, if the alternator is not able to fully supply the fan motor electrical draw, it will not provide the required air flow.
fans generally require a matching fan shroud placed and correctly clearanced on the rear of the radiator to reach the full cooling efficiency, your radiator will generally require about 1.4 square inches of surface area per cubic inch of displacement. your engines water pump must be able to provide the required coolant flow and the t-stat must also not restrict coolant flow rates.
ignition timing effects the engine combustion and exhaust gas temperatures, so thats important.
keep in mind almost all the engines heat is generated in the upper 2" odf the cylinders, combustion chamber and by heat generated in the valve train and rotating assembly, thus OIL FLOW rates are also critical as its OIL flowing over the engines moving components that absorbs and transfers at least 70% of the engines higher temps to the block and coolant, thus adding an oil cooler with a fan to also transfer heat absorbed by that mass of oil will further reduce the heat load on the engine coolant!
with an auto transmission, the heat load the radiator deals with is further compromised by the transmission fluid heat transfer, so adding a trans fluid cooler with an auxiliary fan will again reduce the engines cooling system heat loads.

http://garage.grumpysperformance.com/index.php?threads/thoughts-on-cooling.149/

http://garage.grumpysperformance.com/index.php?threads/how-the-cooling-system-works-basics.853/

http://garage.grumpysperformance.com/index.php?threads/how-to-choose-an-electric-fan-in-4-easy-steps.7774/

http://garage.grumpysperformance.com/index.php?threads/do-i-need-the-fan-shroud.13847/

http://garage.grumpysperformance.com/index.php?threads/auto-cooling-system-flow-rates-and-heat-transfer.9880/

http://garage.grumpysperformance.com/index.php?threads/setting-up-electric-fans-correctly.7150/

http://garage.grumpysperformance.com/index.php?threads/unwanted-engine-bay-heat.12186/#post-59072

http://garage.grumpysperformance.com/index.php?threads/transmission-and-oil-cooler-increases-durability.176/#post-48374
its just a stock 350 L48 no mods it has a shroud on it
 

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Chevy had a High po Flex fan ysed on Big Block cars.
Pretty much unobtainable today.

Pontiac had same on early 1970 TA.
They called it the Power flex fan..
Real deal hard to find.
On my 70 TA.
 

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Really hard to say exact because no one really knows but on a Hot Summer day when the Thermal fan kicks on full locked its pulling somewhere around 5000-10000 cfms of airflow through the radiator.
Cost is Hp. Takes 35-45 crank hp to do it.
To pull 10000 cfm from standard available electric fans is pretty much impossible.
 

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my standard go to is the hard plastic
flex-a-lite fans, either FLX-417 or FLX-418
in the stock shroud and using 1"-2" spacers
to get the fan positioned correctly.

i have NEVER found any electrical fan that will
cool the 500+hp range daily drivers reliably.
just my experience, yours may differ.
 

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I found about that Texas Twister fan a few years ago Zinc. I have not tried it myself.
Many have used it on other forums.
The very worst cooling system situation I have found is when I driving to work.
Stop sudden on Route 80.
Summer and its 90-100F out.
No one moves for 1-3 hours.
20,000-100,000 cars and trucks behind you backef up from Chicago to Iowa West.
The 63 Gp Got hot a few times.
I had to ditch the $650 Be Cool Radiator.
I installed a Bone stock Original 1970 Bonneville 455 Harrison radiator.
Temps Dropped 40 F .
Brass and Copper radiators still work best for me.
Pontiac TA Guys have founf out the same.
I wired the electric fan so it runs all the time with the key on.
No chance of Relay failure that way or electronic black boxes to fail .

Next best radiator is the Griffin Racing. Its 5 inches thick.
Cost is $880.
On my 87 Corvette.
 

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its just a stock 350 L48 no mods it has a shroud on it
You'll be fine.

Tip- the viscous fan clutch works on a sticky silicone fluid. If there is any sign of dust sticking around the seals on the clutch, replace it. Even the tiniest amount of seal leakage and the clutch won't engage 100% causing low speed overheating.

Good luck with your slow & leaky vette :D
 

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A lot of talk here about electric fans without the essential information.

Using an electric fan with our original SI style alternators is a waste of time. Yes, they can be modded to put out 120 amps however that's going down the road, not idling. The newer CS 130/144 alternators solve the idle amp problem.

Electric fans will outperform mechanical fans at idle. All day, every day. No comparison. Because overheating is 90% about idle time.

Any electric fan big enough to support V8 cooling is going to draw more amps than a SI alternator can provide at idle. And when idle volts drag down to 11, those fans are going to cut airflow in half compared to 13.5V. Instant overheating and instant exhaust fumes from low spark voltage. Basic OHMs law stuff, decrease the voltage increase the amperage and heat and low performance result.

However, if a CS 130/144 alternator (or newer) is fitted, voltage/amperage problem solved. It's no coincidence that even junk front wheel drive cars from the 90s used CS style alternators along with their electric fans.

Been doing the modified V8/ electric fan thing since the 80s. These are facts.

Good luck with your slow N leaky vette!
 

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Grumpy has great info.
Its the manufacturers that do not give enough data.
BTU's heat rejection rate.
Best that can be done is share info and personal experiences.
 

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I would stay away with fans that are rivited as one of my friends had a blade come off and do damage. I have tried electric and not successful. Not enough air flowing over the engine when playing around. OK for rad but not enough air flow on rest of engine.
I have a plastic flex fan
https://www.summitracing.com/parts/mar-mfa118
I have run it on two engines in my vet and have had no complaints. Currently running a 383 stroker with aluminum heads close to 500 hp. Good luck
 

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Electric fans will outperform mechanical fans at idle. All day, every day. No comparison. Because overheating is 90% about idle time.

i beg to differ. every electrical fan i have tried--
sho taurus, lincoln mkViii, viper, black magic, etc...
has overheated within 15 minutes at idle. coolant everywhere,
temps 220+and climbing.

the flx-417 idled for 2.5 hours in bumper to bumper
traffic on a 90+degree, 80% humidity day without
spilling a single drop of coolant and the temp gauge
never went over 205.

and no i didnt change anything else--hoses, radiator, waterpump,etc were all same.

this isnt my opinion, its real world experience. maybe just
on my particular combo, but thats what it was.

and YES i did have the correct alternator as well as
70amp relays wired with 10G wire.
 
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