My 81 flareside is going electric!

[Pete Whitstone]

Did someone use the wrong perches, like from a 300 six?

Uh, yeah. That would be me. I took a week off work to pull the straight six out of there and install the 351w. I had to get the project finished in a week. I assumed that since the truck came with both 6's and 8's, that it would be fairly straightforward. I was wrong, obviously. I was not having a lot of luck searching the internet for pictures of the V8 mounting arrangement, but I assumed the engine perches (as I now know they are called - kind of hard to search for something that you don't know the name of) were basically the same between the I6 and V8. When I dropped the V8 engine down, I found there to be a spacing problem with the I6 perches, there was a large gap on either side if about an inch and a half. So, I knew the perches were different from the 6 to the 8, but didn't know how. I assumed the V8 perches were like the I6 perches, just taller. So I modified them to be taller... the overall effect being that the engine sits a bit higher and a bit more forward than it should. I got a driveshaft of the right length and called it good. I was determined to finish the engine install in a week, and I did.

Later of course, I found out that the V8 engine perches actually sit behind the K-member. I think I also learned that they are riveted to the frame, making them a PITA to remove/replace. And here's where my truck chassis gets weird(er). The VIN decodes as an 81 with a 351W, and that's what I wanted in there. But there are a couple things wrong with the chassis for that. First, there was no sign that V8 engine perches were ever in there. Second, the frame is supposed to be an 81, but there are no swiss cheese holes. So I think I've got an 81 body on a later I6 frame. I haven't tried to find the frame VIN, but I know where to look, thanks to you.

So I got a strange truck, and probably made it stranger. Maybe one day I will hunt down the correct engine perches and put things more stock, but for right now I'm not really worried about it. I don't think I have changed the engine angle enough to worry about driveshaft phasing weirdness, but time will tell.

Don't hate me because I don't know these trucks yet!

Also, you may have guessed by now that I am not a "keep it stock" purist. I see enough talk of engine swaps, etc. on this forum that I don't guess everyone is. I respect those who want to restore a truck to stock, but that's not me at all. I love fabbing stuff up or modifying other stuff to work with a vehicle.

[Gary Lewis]

Did someone use the wrong perches, like from a 300 six?

Uh, yeah. That would be me. I took a week off work to pull the straight six out of there and install the 351w. I had to get the project finished in a week. I assumed that since the truck came with both 6's and 8's, that it would be fairly straightforward. I was wrong, obviously. I was not having a lot of luck searching the internet for pictures of the V8 mounting arrangement, but I assumed the engine perches (as I now know they are called - kind of hard to search for something that you don't know the name of) were basically the same between the I6 and V8. When I dropped the V8 engine down, I found there to be a spacing problem with the I6 perches, there was a large gap on either side if about an inch and a half. So, I knew the perches were different from the 6 to the 8, but didn't know how. I assumed the V8 perches were like the I6 perches, just taller. So I modified them to be taller... the overall effect being that the engine sits a bit higher and a bit more forward than it should. I got a driveshaft of the right length and called it good. I was determined to finish the engine install in a week, and I did.

Later of course, I found out that the V8 engine perches actually sit behind the K-member. I think I also learned that they are riveted to the frame, making them a PITA to remove/replace. And here's where my truck chassis gets weird(er). The VIN decodes as an 81 with a 351W, and that's what I wanted in there. But there are a couple things wrong with the chassis for that. First, there was no sign that V8 engine perches were ever in there. Second, the frame is supposed to be an 81, but there are no swiss cheese holes. So I think I've got an 81 body on a later I6 frame. I haven't tried to find the frame VIN, but I know where to look, thanks to you.

So I got a strange truck, and probably made it stranger. Maybe one day I will hunt down the correct engine perches and put things more stock, but for right now I'm not really worried about it. I don't think I have changed the engine angle enough to worry about driveshaft phasing weirdness, but time will tell.

Don't hate me because I don't know these trucks yet!

Also, you may have guessed by now that I am not a "keep it stock" purist. I see enough talk of engine swaps, etc. on this forum that I don't guess everyone is. I respect those who want to restore a truck to stock, but that's not me at all. I love fabbing stuff up or modifying other stuff to work with a vehicle.

You got it done, and that's what counts. And if you go to stock Windsor perches it'l cause the engine to be farther to the rear and your driveshaft will be too long. I'd stick with what you have.

As for not hating you 'cause you don't know these trucks, I sure didn't about 10 years ago, and still don't know that much. But with the help of the guys on here and others I'm learning.

And stock isn't the goal. How you want it is the goal. Neither of my trucks are close to stock.

[Rusty_S85]

Nice, are they going to be both on full tilt or will they come on in stages and ramp up the more air flow you need?

The way they are wired now, yes they just come on full. The fans will support 2 speeds but I have both speeds wired to the same controller so they just come on "high". I toyed with the idea of getting a second variable fan controller ($11) and setting that controller some degrees cooler so they would come on in stages, but I was not sure that was necessary. I can always go back and add that easily enough, if I determine I need it.

I think its a good option because in cooler weather like fall or spring you wont ever have the fans come on full blast so you would have a reduction in fan noise.

That is the biggest thing that keeps me from going electric fans is we install quite a few of them on cars/trucks at work and very rarely do I see one that doesnt sound like a blender running with how loud the fans are. Its why if I ever added one I would do a auxiliary condenser fan and wire it into my fan 1 output on my sniper stealth so it will come on every time the AC is switched on.

Only way I would go full electric right now I think is if I could figure out a way to run a multi rib belt while retaining my dealer installed York A/C compressor. I know ive installed some on other vehicles in the past that use multiple multi rib belts but cant find any for our trucks. I also know chevrolet in the 80`s was using traditional V belts for everything but then had a multi ribbed belt just for the alternator. I would even settle for something like that if it didnt move my A/C belt pulley that bolts onto my crank.

[Pete Whitstone]

Update on the fans - got everything buttoned up and got the truck running again (installed headers and revised the exhaust system).

The new fans are quiet, I would describe the noise they make as a hum, not even a loud hum. They came off a luxury vehicle so I would expect that they be fairly quiet. So how did they perform? In ambient 80+ degree conditions, I let the truck get up to about 210 as indicated by the coolant sensor in the intake manifold. Then I turned the fans on, and they pulled the temps down to 180 in less than a minute, so they seem pretty efficient.

One thing I will have to revise is that I bought a variable temp fan controller whose range was 180 to 245, thinking that I would not want to try to cool below 180. The problem with that is, at idle there is a big lag between what the engine sees temp-wise and what the radiator sees (the bulb sensor to trigger the fans is in the radiator fins). So to deal with that latency, the radiator fans need to kick on at a lower temp than 180 in order to keep the engine from seeing in the 200's. So I will be replacing the $11 180-245 controller with a $17 160-245 controller, Summit part HDA-3653.

I have to rebuild the front end of the truck before I begin road trials, I have ball joints and tie rod ends with torn boots, so they will not last long. I'll know more about how the fan conversion behaves then and will report back.

Happy Memorial Day, all, and thanks to those that served.

Pete

[ArdWrknTrk]

Update on the fans - got everything buttoned up and got the truck running again (installed headers and revised the exhaust system).

The new fans are quiet, I would describe the noise they make as a hum, not even a loud hum. They came off a luxury vehicle so I would expect that they be fairly quiet. So how did they perform? In ambient 80+ degree conditions, I let the truck get up to about 210 as indicated by the coolant sensor in the intake manifold. Then I turned the fans on, and they pulled the temps down to 180 in less than a minute, so they seem pretty efficient.

One thing I will have to revise is that I bought a variable temp fan controller whose range was 180 to 245, thinking that I would not want to try to cool below 180. The problem with that is, at idle there is a big lag between what the engine sees temp-wise and what the radiator sees (the bulb sensor to trigger the fans is in the radiator fins). So to deal with that latency, the radiator fans need to kick on at a lower temp than 180 in order to keep the engine from seeing in the 200's. So I will be replacing the $11 180-245 controller with a $17 160-245 controller, Summit part HDA-3653.

I have to rebuild the front end of the truck before I begin road trials, I have ball joints and tie rod ends with torn boots, so they will not last long. I'll know more about how the fan conversion behaves then and will report back.

Happy Memorial Day, all, and thanks to those that served.

Pete

The coolant thermostat is what's really controlling engine temperature.

Put the thermistor (or whatever) in the upper right corner if you want the fans on sooner.

[Pete Whitstone]

The coolant thermostat is what's really controlling engine temperature.

Put the thermistor (or whatever) in the upper right corner if you want the fans on sooner.

Yup, that's where it's at.

I think in actual operation (driving) it will be fine, since there won't be that big a difference between the manifold temps and the radiator temps. I think that's a product of the thermostat having to come up to temp before the radiator sees any heat, then the radiator itself is slow to heat up and transfer heat into the sensor. Once everything is up to temp, I think the fans will respond much sooner, with regards to the temps in the intake manifold where the gauge sensor is.

Pete

[Gary Lewis]

The coolant thermostat is what's really controlling engine temperature.

Put the thermistor (or whatever) in the upper right corner if you want the fans on sooner.

Yup, that's where it's at.

I think in actual operation (driving) it will be fine, since there won't be that big a difference between the manifold temps and the radiator temps. I think that's a product of the thermostat having to come up to temp before the radiator sees any heat, then the radiator itself is slow to heat up and transfer heat into the sensor. Once everything is up to temp, I think the fans will respond much sooner, with regards to the temps in the intake manifold where the gauge sensor is.

Pete

Yes, I think in actual operation it'll be better. But at least you are watching it closely.

[Pete Whitstone]

Update... The Infiniti FX35 fans were good but they were a little weak in the Texas summer with the AC on. I got tired of having to watch the temp gauge like a hawk. They were also a little slow to bring the temps down when they did kick on. Time for an upgrade. I decided on these fans:

https://www.jegs.com/i/Flex-A-Lite/400/116521/10002/-1

They needed a corner of their shroud trimmed to make them fit around the radiator tubes and transmission lines, but that was pretty easy to take care of. Once that was done, I reinstalled everything and here's what it looks like now.

It comes with an adjustable thermostat as well.

Not much real world experience with them yet, but I have let thhe truck heat up to adjust the thermostat, and when they come on, they drag the temps down very quickly.

Unfortunately they also drag the voltage down pretty quickly too. The voltmeter sits on 12v when they are on, so the alternator is not keeping up. But then it's a 3-decades-old unit from the donor truck, so I guess that's to be expected. I have a 200-amp unit from DB Electrical on the way.

[Gary Lewis]

Update... The Infiniti FX35 fans were good but they were a little weak in the Texas summer with the AC on. I got tired of having to watch the temp gauge like a hawk. They were also a little slow to bring the temps down when they did kick on. Time for an upgrade. I decided on these fans:

https://www.jegs.com/i/Flex-A-Lite/400/116521/10002/-1

They needed a corner of their shroud trimmed to make them fit around the radiator tubes and transmission lines, but that was pretty easy to take care of. Once that was done, I reinstalled everything and here's what it looks like now.

It comes with an adjustable thermostat as well.

Not much real world experience with them yet, but I have let thhe truck heat up to adjust the thermostat, and when they come on, they drag the temps down very quickly.

Unfortunately they also drag the voltage down pretty quickly too. The voltmeter sits on 12v when they are on, so the alternator is not keeping up. But then it's a 3-decades-old unit from the donor truck, so I guess that's to be expected. I have a 200-amp unit from DB Electrical on the way.

Cool! In several senses of the word!

I'm anxious to see what you think of those fans after a while. And, what you think of that alternator. But what is that alternator in your pic? A bolt-on 3G from a 90's vehicle?

[Pete Whitstone]

Cool! In several senses of the word!

I'm anxious to see what you think of those fans after a while. And, what you think of that alternator. But what is that alternator in your pic? A bolt-on 3G from a 90's vehicle?

My entire drivetrain is from a 95 F150 4x4 donor vehicle. That alternator is what I believe was the original alternator on that truck. All 95 amps of it. Well, probably 65 amps, at this point - it's tired.