Upgrade: Installing the longer 2WD 3/4 ton 454 radiator

[austinado16]

Couldn't agree more, but I don't have any spare money.

 

[MikeB]

I don't know what the water pump shaft diameter is, and I simply ordered a GMB high flow replacement based on year/model/counter-rotation. I'm sure it'll be fine since I won't be running the 3" spacer any more.

If you have part numbers or other info for the pumps, can you post it?

I read on a Chevy forum that some early BBC pumps had 3/4" shafts. But all I can find for reverse rotation pumps is 5/8", which is probably what you have. Should be more than enough w/o the spacer.

On another note, I'd bet your engine doesn't overheat pulling your trailer up hills in the summer. And unless you have a super HD fan clutch, I doubt electric fans would be much more efficient, considering their current draw.

 

[austinado16]

Yes, the big radiator has made a noticeable improvement, even over the shorter 4 row big block radiator that I'd been running for a couple years. Got 3 hot weather tows out of it last summer. The 3rd was even with 8 on board, plus the camper. I'm always camping at the same location, so I'm climbing the same long grade each time. Makes it pretty easy to compare the results of different mods.

Wish I could do the fan mod, because it's probably worth 2mpg, which would be pretty nice on a 40gal tank. Not to mention the reduction in engine noise.

 

[gmachinz]

This setup does draw some juice-on low speed it averages 11A, medium speed comes in at around 22A and high speed is right at 36A. A 124A alternator is the minimum I'd say.

 

[1low4x4]

I read on a Chevy forum that some early BBC pumps had 3/4" shafts. But all I can find for reverse rotation pumps is 5/8", which is probably what you have. Should be more than enough w/o the spacer.

On another note, I'd bet your engine doesn't overheat pulling your trailer up hills in the summer. And unless you have a super HD fan clutch, I doubt electric fans would be much more efficient, considering their current draw.

Gonna have to disagree. at least on power...don't know about fuel mileage. The first time you put it in drive and begin to accelerate after installing electric fans, you'll realize the difference. The current draw is tiny compared to the drag an OEM clutch fan puts on the rotating assembly.

OP, search ebay for some electric fans out of like an 04 Aztec or rendezvous. That's what I have in mine and they fit the 4 core radiator almost perfect. They draw plenty of air too. I used the Painless Wiring harness cause we tried some cheap harness on my dads fans that didn't last. But the painless is heavy duty and has three relays.

With the big block radiator, my fans only come on when the truck is at a standstill for a little while. Harness cost more than the fans. I have a stock sized alt. Just some ideas

 

[austinado16]

Thanks for the info! Can you provide more info about the "painless" harness, and about how you're sampling temperature? And I can't tell from your photo, but is your radiator the long version, with the 34" long core (about 38" total to the outside of the tanks). Or is yours the standard length version (28" long core)?

 

[MikeB]

Gonna have to disagree. at least on power...don't know about fuel mileage. The first time you put it in drive and begin to accelerate after installing electric fans, you'll realize the difference. The current draw is tiny compared to the drag an OEM clutch fan puts on the rotating assembly.

I defer to your experience. Mine is limited to a buddy's 56 Chevy with a Be Cool radiator/dual fan setup, which he installed along with a new engine. So, no mpg or acceleration comparisons there.

My C10 has a standard duty fan clutch (not very aggressive) and stays at 180-190 in the summer, but it has a mild 350 and is not used for towing. It's totally different that one I had in a 96 Jeep Grand Cherokee. Sometimes it sounded like a B-29! And it seemed to be either off or on, with no in between. No doubt that thing hurt mpg and performance when it was engaged.

 

[74 Shortbed]

I'll be putting E-fans on mine with the big block, been seriously considering the Winstar heard they move a lot of air..

 

[NOPHO84K30]

windstar fans do move lots of air thats what i have on mine. they keep it cool and cool it fast there only on for a minute or so till it drops below th cut off temp. warning ive never had a problem with fans but a good controller is more important.... you should carry spare wires so you can dirrect connect to batt when it ***** out on you. itll happen you'll be stuck.. ive put three different set ups on mine but i think i have it nailed down now with a 80 amp continuous duty relay and spal controller. but you never know..i went through 2 f5 painless controllers in the WINTER after my first derale failed..i then went to spal i have mine set up to turn on a 80 amp continuous starter relay to power fans so its not running through the controller i had it this way on the derale it lasted a few years but it was an old one a friend gave me that he used so idk how old it was. . ok long enough story..

 

[74 Shortbed]

Thanks, that's what I been hearing so Windstar it is, good note about the controller too, I think a bypass with a toggle switch would be a good idea just in case the controller does take a ****.

 

[yevgenievich]

The only controllers I seen reliable were oem's. A backup switch working the 80amp relay would be a good addition.

 

[1low4x4]

The number 1 failure of Fan controllers are the relays.

I don't have experience with the F5 Painless controllers but I can tell you that $230 dollars for a fan harness is ******* insane. No way in hell I would pay that.

However you do want to pay more than 50 bucks for one. Its just like the electrical in your home. Undersize the wire and buy **** components, you got issues. Buy correct sized wire and quality components, no issues. Problems arise when you start throwing in variable drives and extra crap. You don't need a controller that can run the fans in 3 different speeds. That **** will fail. All you need are quality relays that are properly sized, and a good temp sensor.

We installed the same style fans I have on my truck in my dads square, before I installed mine. He got a 45 dollar controller setup off summit. Single relay for dual fans lmao. It burnt out on me when I was driving his truck and it overheated bad before I could even realize it. Dad went back and rewired in heavy duty relays, one for each fan, and hasn't had a problem since.

Since Im an electrician, I know a little about this stuff so I figured Id wire my own. But once I started looking at this painless kit I decided to use it but modify it a bit.

https://www.summitracing.com/parts/PRF-30117

I was very happy with the quality of the kit. But, I had one problem that I changed. The two relays for the fans tied in together and had one lead that went to a fuse and then to the battery. If the fuse blew, both fans died. So, I separated them and now both have their own fuse and separate lead to battery power.

I installed this kit back in april 16 and daily drove the truck through October, in 100 degree texas heat and have had no issues. Fans do a great job.

OP, I measured my radiator and by your measurements I have the smaller 4 core. Im surprised they even make a bigger one. Needle on my temp gauge barely even moves even towing in third with my radiator.

I consider electric fans the be in the top 3 of the most effective mods Ive done to this truck

 

[Camar068]

Thanks, that's what I been hearing so Windstar it is, good note about the controller too, I think a bypass with a toggle switch would be a good idea just in case the controller does take a ****.

Thanks Shorty, I'll add this to the to-do list when I do the LS swap. Good thinkin.

 

[austinado16]

1low4x4, your link doesn't got to anything. Can you fix it? And maybe I missed it elsewhere, but what fans are you running?

 

[1low4x4]

1low4x4, your link doesn't got to anything. Can you fix it? And maybe I missed it elsewhere, but what fans are you running?

edit: still not working. hmm. Part number PRF-30117. On summit

Running fans off a buick rendezvous