thatcabledude
GOLD Star
Registry 8x Series V8 Swaps (6 Viewers)
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Awesome everyone, I appreciate all discussion. Maybe they’re some particulars to getting it to work. I’m using the stock radiator. Unsure of its age from PO buts it’s not original. It is an all metal replacement though. I took it to a rad shop for cleaning.
What’s your third trigger temp for? Both on simultaneously? Did you tie on to a/c some how or just a function of eng temp?
What’s your third trigger temp for? Both on simultaneously? Did you tie on to a/c some how or just a function of eng temp?
Ah, my fans will either be on or off, but I didn’t want them coming on both at the same time, for electrical load consideration. I assume at highway speeds even with a/c, you’d be below trigger temps, in most scenarios. Thanks.
Good to have an overview of cooling systems. I went with electric fans, as an assumption of ease from what I was able to gather from previous installs.
I would like to wire in the trans temp some how. Has anyone wired in a trans temp switch to illuminate the warning light in the dash? I wasn't sure of the operation of the "in pan" oil temp switch. I believe that just goes to the GM ECM. I was looking at the ability to put in a stand alone temp switch at the pressure test port on a 4L80. Wire that to the dash light. Would be nice to monitor actual temps versus needle in the dash. I guess you could plug in a OBD reader, which should give GM provided temps through OBD port. Any one have a little OBD scanner they use for engine monitoring? I have a 2500 HD diesel, and those are very common to just view boost, injector balance and exhaust EGT.
There has been discussion before on t-stat temps, while I know all that has to do with is getting the engine to a specific operating temp, then opening, obviously a huge issue if it sticks closed, but assuming normal operation, what is the school of though on the different temps for the t-stat, Im a novice, but from what I've read, the LS family likes to be about 190-200 degrees, what are the reasons for the 180 vs 190 degree t-stats? I guess for me, living in TX, I'll probably go with the lower temp t-stat, to get "on top" of the heat situation sooner rather than hotter, as getting to 200 - 210 isn't going to be an issue.
I assumed if I have cooling issues, Id go with a larger capacity radiator to increase coolant capacity, and add a fan to the front of the trans cooler. Well see!
I would like to wire in the trans temp some how. Has anyone wired in a trans temp switch to illuminate the warning light in the dash? I wasn't sure of the operation of the "in pan" oil temp switch. I believe that just goes to the GM ECM. I was looking at the ability to put in a stand alone temp switch at the pressure test port on a 4L80. Wire that to the dash light. Would be nice to monitor actual temps versus needle in the dash. I guess you could plug in a OBD reader, which should give GM provided temps through OBD port. Any one have a little OBD scanner they use for engine monitoring? I have a 2500 HD diesel, and those are very common to just view boost, injector balance and exhaust EGT.
There has been discussion before on t-stat temps, while I know all that has to do with is getting the engine to a specific operating temp, then opening, obviously a huge issue if it sticks closed, but assuming normal operation, what is the school of though on the different temps for the t-stat, Im a novice, but from what I've read, the LS family likes to be about 190-200 degrees, what are the reasons for the 180 vs 190 degree t-stats? I guess for me, living in TX, I'll probably go with the lower temp t-stat, to get "on top" of the heat situation sooner rather than hotter, as getting to 200 - 210 isn't going to be an issue.
I assumed if I have cooling issues, Id go with a larger capacity radiator to increase coolant capacity, and add a fan to the front of the trans cooler. Well see!
I got this done, definitely easy to do. Cost is $8 for a new cable end from auto zone.
I ran a stock all brass radiator with electric fans on my L92/6L80 swap for about a year. It never overheated, but got up into the mid 220's while towing a 1,500 pound off road trailer out west (temps in the mid to high 90's). Decided to drop the coin on the Ron Davis radiator, shroud, and dual 13" Spal fan set up they sell. Can't say enough good about that product, and haven't seen anything above 210 degrees since.
Regarding setpoints, I've got my ECM set up to trigger the fans at 195 and 200 degrees, but also wired in a trinary switch from the A/C to kick the 200 degree fan on when A/C system pressure gets high. There's some good reading about that here:
ABC's of 80's A/C and Cooling - Part 1
Part I - The Need for Aux Cooling Now that Chicago is hitting 100, figured it might be a good time to put some data and thought into our 80’s issues of (over)heat. Since we don’t have a lot of data in regards to things like our Toyota Engine driven Thermo/Fan CFM, RPM and other factors that...
forum.ih8mud.com
What part of my statements do you disagree with and on what basis?
It's real easy to say "WRONG!"
Explain yourself.
I will state my experienced opinion a different way- Electric fans cannot work in applications where the power needed to turn the cooling fan exceeds the capability of available electric fans. In situations where the cooling requirements are minimal, electric fans work fine.
A cooling system's heat removal capacity is based on engine efficiency, time under % load, ambient temp, core volume, frontal area, etc.
Saying "electric fans cool high HP fine" misses the other dozen factors in the equation. How long was it at high load?
So here's some super basic dumbed down electric VS mechanical fan facts-
-Mechanical fan's power limitation is the belt that drives it. That's about 20HP.
-Electric fans typically use 10 AWG wiring. 10 AWG wire is good for 40 amps. 40 amps at 14 VDC is 560 watts. 560 watts is .75HP. Electric fans don't run at the ragged edge of the current capacity of the system and they don't get 14 volts at idle. A half of one HP is all you get to spin that electric fan.
You can make a bigger fan motor and feed it with larger wire, but what size is the wiring from the alternator to the battery in most vehicles? It's 10 AWG. So while an alternator can output more momentarily it cannot overcome a continuous load of more than about 40 amps.
So you're driving your LS swapped 4L60E loaded with gear 8000 lb cruiser on 35" tires on a 95 degree day with the AC on. The radiator needs to dissipate the heat from the transmission, the AC condenser and of coarse the engine. And you start up a steep grade at 45 MPH. How well are your electric fans going to cope with that?
At 45mph, air flow is sufficient to cool the radiator core without fan consideration. Low speed operation is where the debate exists on electric vs. mechanical. At highway speeds, core stack thickness, frontage area, construction materials, and air flow are the real considerations in effective heat exchange and cooling.
Fair enough. Assume a lower speed, moderate load situation for a land cruiser if you like.
In my experience, I need mechanical fans the most in the 45-55 MPH range when towing heavy. Airflow through the cooling package is not adequate even at those speeds and the mechanical fan fully engages on hot days when towing.
I've made several journeys towing around 30K lbs gross with Dodge Cummins and Superduty stickshift 1 ton pickups from the LA area up to Portland. 45 MPH up the Grapevine and the Siskiyou grades is 200+ HP continuous and that big mechanical fan is fully engaged. And you can hear it and feel the power loss when it engages.
The electric fan clutch failed on a 6.0 Powerstroke I had in my F-350. I found out while going up a light hill on the freeway at 60 MPH @ 29K gross south of Seattle on an 80 degree day. 250 degrees in an instant.
Mechanical fans help significantly with cooling even at freeway speeds.
In an 80 series you may never have an issue with electric fans. Just realize electric fans offer zilch for reserve cooling airflow if you find yourself in a higher load situation on a hot day.
thatcabledude
GOLD Star
Exactly.
These guys have a bit more experience than I do with cooling systems. See rule #2 here:
Radiator Cooling : Griffinrad.com | Frequently Asked Questions Tips to help you
Radiator Cooling : Griffinrad.com | Frequently Asked Questions, Tips to help you obtain the maximum operating efficiency of your cooling system
www.griffinrad.com
Thanks for all the inputs, No disagreement that a mech fan probably moves more air, hopefully this will work. My LC comparison to a 3500 diesel towing a load isn’t really apples to apples. I went with this set up for ease of install on the swap. Currently don’t plan on towing with it. I have a diesel for that. This is for family cruising to the national parks and hunting trips. And of course the end of the world bug out.
In my experience retrofit electric fans do not work well in hotter climates. Your experience being different doesn't make me wrong.
Everyone's experience is different as I am certain mine is different than yours. I own a pretty good size manufacturing company that makes automotive products. I have been making cooling system products among other things for 2 decades of my life.
My opinion that you shouldn't bank on electric fans working in tough environments is formed from the experience of making and selling electric fan products we tested in the NW that failed miserably in hot climates in the Southern USA.
You have your opinion based on YOUR Land Cruiser and how YOU use it. I formed my opinion from working with thousands of vehicle owners to rectify cooling problems caused from high end electric fans that underdeliver when it counts.
My opinion is if you are LS swapping your cruiser to increase reliability VS the Toyota engine it would follow the theme of reliability to use an appropriate thermostatic clutched mechanical fan. If you want maximum efficiency use an electric fan, but don't marginalize the fact you may be compromising reliability in the process.
I brought up my diesel pickup towing experience to illustrate how cooling fans do in fact supplement airflow through the cooling package at higher speeds. While I completely understand that an 80 series will not be towing heavy loads, the point I was hoping to make sharing my experience is simply that fans are important at higher speeds.
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Well now that the debacle of the mechanical vs. electrical fans is over. Thanks to everyone for their insight. Good dialog is key to making this process as easy as possible for others to follow. I should be on the road soon, and can give some data points on my set up for others to make a determination if it'll work in their set up.
To another point, Im looking at where Im going to pick up my TCC input for my PCM. I believe the GM PCM wants 12 volts constant and removed when brakes are applied, so looking at the FJ80 EWD, that looks how the cruise control portion of the brake pedal switch is wired. So I see I can simply splice in IGN power on one side and the other to the PCM.
My thought is, trying to not disturb the TOYOTA cruise system. I did try and look, but has anyone managed to get the toyota cruise system to work with a GM drive by cable vehicle. I feel like it should still just work, minus the inputs / outputs to the toyota ECM and trans PCM. So before I bypass those wires just seeing if anyone has kept the toyota cruise system for DBC GM motors.
Right now, Im thinking of disconnecting the cruise ECM and the cruise actuator, splicing in those wires for now, until I can revisit cruise at another time.
To another point, Im looking at where Im going to pick up my TCC input for my PCM. I believe the GM PCM wants 12 volts constant and removed when brakes are applied, so looking at the FJ80 EWD, that looks how the cruise control portion of the brake pedal switch is wired. So I see I can simply splice in IGN power on one side and the other to the PCM.
My thought is, trying to not disturb the TOYOTA cruise system. I did try and look, but has anyone managed to get the toyota cruise system to work with a GM drive by cable vehicle. I feel like it should still just work, minus the inputs / outputs to the toyota ECM and trans PCM. So before I bypass those wires just seeing if anyone has kept the toyota cruise system for DBC GM motors.
Right now, Im thinking of disconnecting the cruise ECM and the cruise actuator, splicing in those wires for now, until I can revisit cruise at another time.
My only regret when wiring up my electric fans was wiring a low and high speed. I am going to rewire it so I have high speed only. I was never able to find a gm fan clutch that I liked. They all locked up at off times. I thought about installing a tundra fan flutch. But went electric.
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On 80's (and 60's) I go right from the brake switch. This is backwards from the GM schematic but still works perfectly. The PCM just sees a delta not necessarily a +/-
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Wow, really thanks for heads up. So I’ll just tap into the brake light wires. Bit of a novice, would there be a way for me to tell if it’s working or not? That the TCC is locking or unlocking when it should? Thanks for the help.
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The default is TCC locked, with TCC locked in 1st gear your brakes will likely not be able to hold the vehicle at a stop. Highly recommend doing 1st drive with tires off the ground on any swap to make sure brakes can stop the vehicle in gear, clutch works (on manual transmission swaps), etc
