Fan options

[pat]

Im trying to decide what to do with my fan. Ill be running a 383 with headers and a/c in Texas, so Ill need plenty of air moving. I was looking at flex fans, but I dont think they move enough air. I thought about electrical, but they are pricey. Then there is the stock fan.
What do you guys recommend?

[rambler]

I heard nothing but negitive about flex fans (not sure why) but make sure you have a fan shroud to help with whatever you use.. I dont have a/c and a standard 350 w/o headers, so with my new grill and such, I just put one 18" electic.. in the FAQ section there is a post about using a double electic off a acura I believe.. wish I saw that before buying mine.. I think one electric is good enough for me, but check out the FAQ,, that may be your answer... good luck..

[sleepyboy]

I live in San Antonio; 350 with vintage air. Switched to a 4 core radiater and dual electric fans; no problems...

[smokekiki]

This article is one of the reasons..http://www.worksafebc.com/publicatio...wsflexfans.pdf Flex fans have come apart and have caused some deaths.

[Classic Heartbeat]

I personally like our duel 12" electric fan assembly. I use them on small blocks, and big blocks without having any problems at all and I tow a couple of pretty big trailers. I am not down in the Texas heat, but I have sold many of these assemblies to guys that are. WES www.ClassicHeartbeat.com

[rambler]

Here is the link in the FAQ section...

http://67-72chevytrucks.com/vboard/s...d.php3?t=50085

[chipflyer]

When the stock fan clutch locked up on me I replaced it with a flex fan on my 71 with AC and it worked ok during the fall and winter months but when I fired up the A/C a couple of weeks ago the truck would run a little warmer than I was comfortable. I replaced the flex fan with a new clutch and the original 7 blade fan and it was much better. Last week I replaced the 3 core radiator with a new 4 core and now the temp needle just comes up a little bit regardless of weather its warm outside or the A/C is on.
After trying the flex fan myself, I wouldn't put one back on. I give it a thumbs down.

[speedracer]

flex fan

[mocwon]

Flex-A-Lite 210 low-profile, sucker, dual fans from Summit with thermostat $237 pumping out 2,500 cfm. These fit and work great down here around the Equator, I mean Texas.

[chickenwing]

I have that set up. I like it. Could I bother you with a pic how you have it mounted?

Here is how I mounted the top:

[LUV2XCLR8]

Alot of peeps use the one WES sells or the one CHICKENWING has,
the one WES sells is in his online catalog, the other is from JEG'S,
it is #400-295 and run by alot of members here, they are both
ASA (SEE-TEN) has this one from JEG'S on all three of his rides.

[mocwon]

Originally Posted by chickenwing

I have that set up. I like it. Could I bother you with a pic how you have it mounted?

Here is how I mounted the top:

I'd be happy to but it'll have to wait until next week since I won't be at the shop this weekend. I'm using a four-core big block radiator I bought from Four Season so it may look different than yours.

[see ten]

Originally Posted by LUV2XCLR8

Alot of peeps use the one WES sells or the one CHICKENWING has,
the one WES sells is in his online catalog, the other is from JEG'S,
it is #400-295 and run by alot of members here, they are both
ASA (SEE-TEN) has this one from JEG'S on all three of his rides.

Yep! All electric here! No complaints except for my light hip pocket! By the way not only will it cool well, it will increase the mpg for you.

[bagged91]

While it wasn't in a 67-72 truck, I used dual elect fans on my 88 K2500. I had a built 383 stroker in that, stock 350 HD radiator and dual Hayden 14" electric fans(I believe they flowed 1800 cfm each)that I picked up locally at PepBoys(of course, I had to got to two different stores as each one only had one in stock). Fans cost me approx $86 ea and the thermostat kit to run dual fans was another $35. I bought a sheet of 18ga aluminum from my local metal supplier, cost around $20 and bent it to make a shroud to fit the radiator core, staggered the fans and cut out the circles accordingly. With headers, A/C on in the middle of summer, truck never went over 185 degree's. I am running a similar setup on my 91' GMC now with NO SHROUD and it runs the same.

[Mongo]

Originally Posted by smokekiki

This article is one of the reasons..http://www.worksafebc.com/publicatio...wsflexfans.pdf Flex fans have come apart and have caused some deaths.

Aww, I was disapointed I thought that link would have been the pic of a fan blade that had gone through the hood. still worth the read though.

[71RestoRod]

When it really comes down to it, I don't think you can beat the cooling power of a clutch fan and well positioned shroud. Having said that, though... I too went with the Flex-a-lite dual fan setup ...

Originally Posted by chickenwing

I have that set up. I like it. Could I bother you with a pic how you have it mounted?

Here's how I mounted mine...

Mounting the Flex-a-lite takes a little bit of creativity. The brackets they provide are overly universal and really leave you scratching your head.... so I basically threw them in the trash. (I see you did too! I like your solution... looks really clean)

I'm running a 383 w/ AC also, so I first upgraded to a four core radiator. I made eight clips out of some light bar stock that hook to the top and bottom core supports. With a little trial and error I finally got them dimensioned so they hold the dual fan assembly tightly to the radiator.

Once I got the assembly mounted, I was kind of disappointed at the considerable nest of wires that sprouted out of the top of the assembly, in the location that the directions called for mounting the relay. (BTW, the relay is the sweetest part of the fan setup because it's totally adjustable and operates with variable speed depending on the demand.) After staring at it for some time, I finally ripped it out again and cut another air-bypass hole where the relay was and moved the relay to the left side of the radiator support next to where I had mounted my headlight relays. I made a new top rubber flap identical to the lower bypass.

I haven't had a chance to really stress it yet, but it seems to work really well. It cycles nicely, remains on for a short period of time after you shut down the engine, and runs at a quiet 60% when the trinary switch off the AC triggers it.

Here are a few pics of the install:

[bobs409]

Originally Posted by Mongo

Aww, I was disapointed I thought that link would have been the pic of a fan blade that had gone through the hood. still worth the read though.

Is this the pic your thinking of? This is what happened to the stainless steel flex fan on my truck. I was driving it at about 50 mph when it happened. It sounded like a boulder landed on my roof and then the truck started shaking like all heck, felt like I was riding on 4 flats. (out of balance fan after losing a blade)

Just glad I wasn't poking my head under the hood revving the engine when that happened.

BTW, that didn't just go through the flat steel, it also went through the under hood reinforcement! I had to remove it with a hammer!

This fan was on my truck when I bought it but I sure won't use anymore! They should be pulled from every shelf.

Anyone that is using one of these, I suggest you take it off now and throw it away.

[Bamm]

Hey Bob. my uncle's 78 4x4 has the exact same hole in the hood!! Now you could gold plate a flex fan and he would throw it in the trash. I would never run a flex fan on anything. They are cheaply made and as you can see, are prone to disassembling themselves at any time. ...............Jerry

[Mongo]

Originally Posted by bobs409

Is this the pic your thinking of? This is what happened to the stainless steel flex fan on my truck. I was driving it at about 50 mph when it happened. It sounded like a boulder landed on my roof and then the truck started shaking like all heck, felt like I was riding on 4 flats. (out of balance fan after losing a blade)

Just glad I wasn't poking my head under the hood revving the engine when that happened.

BTW, that didn't just go through the flat steel, it also went through the under hood reinforcement! I had to remove it with a hammer!

This fan was on my truck when I bought it but I sure won't use anymore! They should be pulled from every shelf.

Anyone that is using one of these, I suggest you take it off now and throw it away.

Yep that be the one

[71Dragtruck]

Originally Posted by mocwon

Flex-A-Lite 210 low-profile, sucker, dual fans from Summit with thermostat $237 pumping out 2,500 cfm. These fit and work great down here around the Equator, I mean Texas.

Would love to see some pics of this setup, I have very limited space and this is the only dual setup I've seen that will fit. A little more CFM would be nice.

[chickenwing]

Thanks 72RestoRod. I was indeed scratching my head on this install. I had no clue what to do. Trashed my brackets also. Was courious what others had done. Never occured to me to make a bracket like yours. Looks nice. Figure mine came out ok. I had some stainless sheet layin around I had snagged from a scrap pile. I installed a some threadserts into the radiator core supports, cut 2 rectangles out of the sheet and was in business. Tucked in real nice under the radiator cover I got from LMC.

Oh if anyone trys what I did... Make sure you use a drill stop.

[4x4Poet]

Originally Posted by pat

... Then there is the stock fan....

If you meant a 6 blade fan, chipflyer is right about the 7-blade fan's superiority to all mech fans:

Originally Posted by chipflyer

...I replaced the flex fan with a new clutch and the original 7 blade fan and it was much better. Last week I replaced the 3 core radiator with a new 4 core and now the temp needle just comes up a little bit regardless of weather its warm outside or the A/C is on....

This seven-blade fan, whether stock or off another GM vehicle, is the ticket for anyone who doesn't mind the small hp loss with mech fans. It really pulls good air when properly shrouded and with a new fan clutch (~$40) that will last 100k plus, trouble-free miles. I hate the electric setups since I never want to gain a little extra hp for the track (or extra fun). With all due respect to our drag racers and general go-fast folks, the stock fan clutch with a 7-blade, GM fan and 4-core radiator all cools better than most folks need while towing uphill in the hottest part of the country. So it boils down to whatchya want: Just economical, uncomplicated, good cooling or expensive, complicated, good cooling +extra hp.

The 7-blade costs $100 new at the stealership, but used ones can be found in wrecking yards on many GM cars and trucks. If you go used, have it magnafluxed to check for cracks and be sure to find out the cost of doing so before you pay the wrecking yard too much where a new one would be easier, prettier, and sure. Classic Industries sells the 7-blade GM fan for $100 but they do have 10% or 20% off sales now and then. Not my favorite vendor, though (to say the least).

[Mudder]

At the time I went electric the guy at Jegs told me the Perma Cool metal blade fan would move the most air. The on I got is rated at 2950cfm's. Works great and have used it going on 3 summers here in MO. I have one of Wes' shrouds for a single fan.

[GMC AMI]

Electric fans are cheap and plentyful at the junk yards. We always put them on drag cars with no overheating problems. I use one on my 656 hydro tractor for extra cooling
while making hay when the sun shines, gets a lot of strange looks!

[mocwon]

Originally Posted by chickenwing

I have that set up. I like it. Could I bother you with a pic how you have it mounted?

Here is how I mounted the top:

1" square tubing top and bottom with socket nead screws through the radiator top and bottom supports. Shortened mounting brackets to work. I still need to take it back apart to paint it.