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CK5
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I didn't see a redneck comment like that coming....I'll drill new holes and lower the tank first.
Just use some strap and drop'em down about 6".
Cuz a filler neck inside the bed wouldn't work, definitely not..
What I notice is the 73 filler neck kinda swoops down and hose is basically level. The 89 is a straight angle from the bedside to the tank. It might be the bit of level lose and just a short bit of angle that creates the issue.
Sometimes I do get a little splash out of the 89, but nothing like the 73.
Sometimes I do get a little splash out of the 89, but nothing like the 73.
Do the nozzles in your area have the spring loaded emissions seals? The 73 should have the larger opening, leaded gas filler neck which doesn't hold the filler at the right angle when using unleaded nozzles. Add to that the emissions spring loaded nozzle and it is a pain filling the older trucks.
No they don't add any fancy contraptions to the pumps here. At most there might be a rubber flange.
The filler hose for an 89 TBI pickup worked well. I cut a small piece of the original hose, just enough to cover the end of the filler neck. The new hose fit over that nice and snugly. I had to use a brass barb adapter for the vent hose, 1/2" to 5/8". The smaller hose being the original '73. I ordered a molded elbow hose for the 5/8" size. Here's how it ended up.
The only 1/2" hose I had was -8 AN stuff.
I also had to cut about 1" off the '89 filler hose from the end that meets the filler neck.
It was a pretty tight fit between the 2 hoses on the end of the filler neck since they are larger than original. I had to take the hose clamp apart to push it thru between the hoses on the larger filler hose; it had just enough room to slip thru.
The filler hose for an 89 TBI pickup worked well. I cut a small piece of the original hose, just enough to cover the end of the filler neck. The new hose fit over that nice and snugly. I had to use a brass barb adapter for the vent hose, 1/2" to 5/8". The smaller hose being the original '73. I ordered a molded elbow hose for the 5/8" size. Here's how it ended up.
The only 1/2" hose I had was -8 AN stuff.
I also had to cut about 1" off the '89 filler hose from the end that meets the filler neck.
It was a pretty tight fit between the 2 hoses on the end of the filler neck since they are larger than original. I had to take the hose clamp apart to push it thru between the hoses on the larger filler hose; it had just enough room to slip thru.
Spent the past 4 or 5 weekends putting an Edelbrock Pro-Flo 4 system in the C10. I picked this system up from @folkenheath with the Volcano intake mod. https://volcanomanifolds.com
You can just make out the Volcano device thur the throttle blades.
Everything in the box.
The allen wrench in the middle foreground is something that @folkenheath includes so that you can make changes to the Volcano device.
Before I had the Pro-Flo on-hand, I was curious about the size of the ECU so I took pictures and measurements if anyone is interested.
First mistake I made was mounting the O2 sensor. I took it down to our business where we have a welder. The Pro-Flo comes with a plug to install after you weld the bung in. I brought the O2 sensor with me so I could make sure I didn't put the bung somewhere I couldn't get the O2 sensor installed. When I was done, I figured since I had the O2 sensor with me I should go ahead and install it now. So I drove it home with the O2 sensor installed. Then a couple days later I was reading thru the Pro-Flo instructions and read a warning about not driving with the O2 sensor installed and unplugged because damage WILL occur. Edelbrock put the emphasis on WILL. So that sucked. I went ahead and bought a replacement because I didn't want to mess with a questionable sensor on a new install.
I'm not proud of my welding job, so this is the best picture you get on where I put the O2 sensor. It's in the down pipe about 6" from the passenger manifold.
When I started pulling the manifold, I realized the AC compressor bracket wasn't going to work with the fuel rails. Same goes for the trans kickdown cable bracket.
Did some searching a found that people leave that AC bracket off without trouble as long as you have the lower bracket to the exhaust manifold; which I do.
You can just make out the Volcano device thur the throttle blades.
Everything in the box.
The allen wrench in the middle foreground is something that @folkenheath includes so that you can make changes to the Volcano device.
Before I had the Pro-Flo on-hand, I was curious about the size of the ECU so I took pictures and measurements if anyone is interested.
First mistake I made was mounting the O2 sensor. I took it down to our business where we have a welder. The Pro-Flo comes with a plug to install after you weld the bung in. I brought the O2 sensor with me so I could make sure I didn't put the bung somewhere I couldn't get the O2 sensor installed. When I was done, I figured since I had the O2 sensor with me I should go ahead and install it now. So I drove it home with the O2 sensor installed. Then a couple days later I was reading thru the Pro-Flo instructions and read a warning about not driving with the O2 sensor installed and unplugged because damage WILL occur. Edelbrock put the emphasis on WILL. So that sucked. I went ahead and bought a replacement because I didn't want to mess with a questionable sensor on a new install.
I'm not proud of my welding job, so this is the best picture you get on where I put the O2 sensor. It's in the down pipe about 6" from the passenger manifold.
When I started pulling the manifold, I realized the AC compressor bracket wasn't going to work with the fuel rails. Same goes for the trans kickdown cable bracket.
Did some searching a found that people leave that AC bracket off without trouble as long as you have the lower bracket to the exhaust manifold; which I do.
Dammit, hit the post button by accident. Well, there's more to come yet.
The next issue I discovered when test fitting the Pro-Flo on the block. The valve cover hit the intake on the passenger side. This was because I had replaced the valve cover gasket on the driver side but not the passenger side. Below you can see it hits on the intake runner.
Driver side close, but clears.
Some others have had the same problem and the instructions mention some clearancing might be needed. I just installed the other replacement gasket to match the driver side.
That solved it.
Cleaned up the old gasket material and got the intake installed and torqued down.
The next issue was the alternator bracket; it wouldn't bolt to the thermostat housing anymore.
For the time being, I have just cut that tab off. I wanted to keep this bracket because it has the clamp to hold the AC and heater hoses in place. Later I will weld it back on to fit.
Next up was the fuel system. I think this probably took the most time. My plan had been to run a TBI pickup tank with a TBI sender and EP381 or Walbro equivalent. I could not find a TBI sending unit in stock anywhere. Plan B was an external pump. @folkenheath helped me find the best pricing which turned out to be an Edelbrock kit that includes a Walbro pump and adjustable pressure regulator. https://www.edelbrock.com/inline-fu...tric-fuel-pump-3594-regulator-1728-35943.html There are probably cheaper setups but I specifically wanted the Walbro pump and this was the best pricing to get both the pump and regulator I needed.
They don't say it anywhere I saw on the Internet listings, but it is a Walbro pump.
Another advantage is this system is kinda designed for the Pro-Flo 4 because at 43psi it will draw less than 10 amps. That means it will run directly of the harness. This is something Edelbrock specifically points out in the description.
I'm still running the TBI tank so it has the sump pan for the fuel pickup. Old versus new.
Here's a picture of the baffle tray inside the tank.
Then I ordered a carb style sending unit with a return line; my truck didn't have a return.
I was going to run hose all the way from the fuel rail to the tank, but then decided to use some nickle-copper hard line with rubber line at each end. I was looking for a way to make a hose barb on the ends of the hard line and I came across this $30 "bubble" flare tool.
It works great!
My plan with the external pump was to keep it back away from the cab in case it was noisy (which it's not), I used the factory hard line feed and vent and added the new return line. Here's the factory setup:
The feed line goes thru the frame and the vent line goes over the top with a short piece of hard line in the middle. For the new setup, I ran the feed line to the rear of the cab mount and used the hole in frame for the return line and mirrored the hardline to the factory feed hard line. The vent is over the top of the frame but with all rubber in an abrasion protection sleeve.
The pump is on a bracket to get it at the bottom of the tank. I put a piece of rubber between the bracket and the frame for extra sound and vibration isolation.
The only thing I didn't foresee was the emergency brake cable being all up in the fuel pump's business.
The inlet line is zip tied over and you can see I added a shield to the outlet hose. It doesn't touch the cable, but I was thinking there's some chance it could bounce against in some situations. This was one of those situations where I had a plan and at the end of executing it, I realized I could have done it differently and maybe better.
I was thinking you could move the pump all the way up to front of the tank and it would be inside the frame rail but still at the bottom level of the tank. However you would have a little longer suction line. And the factory hard line would need to be cut down. Also the pump would be right under the cab. So I'm not sure how much better that location would be, but I think if this was a trail rig I would have gone with that option.
I can report the pump is not noisy enough to bother me. You can't hear it at all in the cab over the exhaust noise. I can hear it standing outside the truck, but it's pretty slight.
Picture upload limit reached. More on the next post.
Driver side close, but clears.
Some others have had the same problem and the instructions mention some clearancing might be needed. I just installed the other replacement gasket to match the driver side.
That solved it.
Cleaned up the old gasket material and got the intake installed and torqued down.
The next issue was the alternator bracket; it wouldn't bolt to the thermostat housing anymore.
For the time being, I have just cut that tab off. I wanted to keep this bracket because it has the clamp to hold the AC and heater hoses in place. Later I will weld it back on to fit.
Next up was the fuel system. I think this probably took the most time. My plan had been to run a TBI pickup tank with a TBI sender and EP381 or Walbro equivalent. I could not find a TBI sending unit in stock anywhere. Plan B was an external pump. @folkenheath helped me find the best pricing which turned out to be an Edelbrock kit that includes a Walbro pump and adjustable pressure regulator. https://www.edelbrock.com/inline-fu...tric-fuel-pump-3594-regulator-1728-35943.html There are probably cheaper setups but I specifically wanted the Walbro pump and this was the best pricing to get both the pump and regulator I needed.
They don't say it anywhere I saw on the Internet listings, but it is a Walbro pump.
Another advantage is this system is kinda designed for the Pro-Flo 4 because at 43psi it will draw less than 10 amps. That means it will run directly of the harness. This is something Edelbrock specifically points out in the description.
I'm still running the TBI tank so it has the sump pan for the fuel pickup. Old versus new.
Here's a picture of the baffle tray inside the tank.
Then I ordered a carb style sending unit with a return line; my truck didn't have a return.
I was going to run hose all the way from the fuel rail to the tank, but then decided to use some nickle-copper hard line with rubber line at each end. I was looking for a way to make a hose barb on the ends of the hard line and I came across this $30 "bubble" flare tool.
It works great!
My plan with the external pump was to keep it back away from the cab in case it was noisy (which it's not), I used the factory hard line feed and vent and added the new return line. Here's the factory setup:
The feed line goes thru the frame and the vent line goes over the top with a short piece of hard line in the middle. For the new setup, I ran the feed line to the rear of the cab mount and used the hole in frame for the return line and mirrored the hardline to the factory feed hard line. The vent is over the top of the frame but with all rubber in an abrasion protection sleeve.
The pump is on a bracket to get it at the bottom of the tank. I put a piece of rubber between the bracket and the frame for extra sound and vibration isolation.
The only thing I didn't foresee was the emergency brake cable being all up in the fuel pump's business.
The inlet line is zip tied over and you can see I added a shield to the outlet hose. It doesn't touch the cable, but I was thinking there's some chance it could bounce against in some situations. This was one of those situations where I had a plan and at the end of executing it, I realized I could have done it differently and maybe better.
I was thinking you could move the pump all the way up to front of the tank and it would be inside the frame rail but still at the bottom level of the tank. However you would have a little longer suction line. And the factory hard line would need to be cut down. Also the pump would be right under the cab. So I'm not sure how much better that location would be, but I think if this was a trail rig I would have gone with that option.
I can report the pump is not noisy enough to bother me. You can't hear it at all in the cab over the exhaust noise. I can hear it standing outside the truck, but it's pretty slight.
Picture upload limit reached. More on the next post.
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The other end of the fuel system at the engine. I put a straight hose barb threaded in to the fuel rail. Mounted the regulator to a threaded boss on the intake with a bracket. The regulator has -6AN adapters that you have to buy separately; they aren't included with the regulator.
The feed and return lines run behind the alternator down to the hard lines on the frame.
I'm planning to put some heat shield around the hoses for good measure. I'm not as worried about it with factory manifolds as I would be with headers.
Next up was routing the harness. I routed it up from the back thru the area on the driverside of the distributor. It's a little tight on this truck because of the oil pressure line.
I've been using the Mag-Daddy magnetic ziptie holders since I put the EFI in the crew cab. They work good for stuff like this. They are routing the harness under the AC housing.
The ECU is mounted on the inner fender.
Tried as best I could to bundle the harness on the intake. I intentionally routed everything by the most lengthy route to use up all of the harness length. The O2 sensor wiring is really the only thing that has a lot of extra length.
Below you can see where I bolted the return spring under the thermostat housing bolt. The bracket did come in the kit.
In the next picture you can see the Edelbrock throttle cable bracket I purchased. The kit doesn't include one and I needed something for the trans kickdown.
I drilled out the oil breather tube adapter in the air cleaner base to install the air temp sensor.
The finished install.
I did have to buy a new base for my air cleaner. It was a drop base, maybe an inch, and it hit the throttle cable bracket. Summit had a 3/4" raised base that works well.
I took it for a test drive and the throttle response is awesome. I always thought it was pretty good with the carb, but it's even better now! I'm excited to start driving to work every day again.
I did notice now that I have a digital readout of engine temperature, it does not warm up at all this time of year. Obviously it does fine idling in the garage but running down the highway it cooled off to under the 165° learning temperature. That's how I noticed it because I saw it wasn't doing the "O2 Learn" and thought what the heck?! Today was about 50° and the engine was running 154°.
I might rethink the big block radiator in this truck. Need to re-exam how it does in the summer with the AC running. For now I'll block the grille like I do with the crew cab. This is my temporary redneck solution.
The feed and return lines run behind the alternator down to the hard lines on the frame.
I'm planning to put some heat shield around the hoses for good measure. I'm not as worried about it with factory manifolds as I would be with headers.
Next up was routing the harness. I routed it up from the back thru the area on the driverside of the distributor. It's a little tight on this truck because of the oil pressure line.
I've been using the Mag-Daddy magnetic ziptie holders since I put the EFI in the crew cab. They work good for stuff like this. They are routing the harness under the AC housing.
The ECU is mounted on the inner fender.
Tried as best I could to bundle the harness on the intake. I intentionally routed everything by the most lengthy route to use up all of the harness length. The O2 sensor wiring is really the only thing that has a lot of extra length.
Below you can see where I bolted the return spring under the thermostat housing bolt. The bracket did come in the kit.
In the next picture you can see the Edelbrock throttle cable bracket I purchased. The kit doesn't include one and I needed something for the trans kickdown.
I drilled out the oil breather tube adapter in the air cleaner base to install the air temp sensor.
The finished install.
I did have to buy a new base for my air cleaner. It was a drop base, maybe an inch, and it hit the throttle cable bracket. Summit had a 3/4" raised base that works well.
I took it for a test drive and the throttle response is awesome. I always thought it was pretty good with the carb, but it's even better now! I'm excited to start driving to work every day again.
I did notice now that I have a digital readout of engine temperature, it does not warm up at all this time of year. Obviously it does fine idling in the garage but running down the highway it cooled off to under the 165° learning temperature. That's how I noticed it because I saw it wasn't doing the "O2 Learn" and thought what the heck?! Today was about 50° and the engine was running 154°.
I might rethink the big block radiator in this truck. Need to re-exam how it does in the summer with the AC running. For now I'll block the grille like I do with the crew cab. This is my temporary redneck solution.
Some big points I learned in this process; mostly with the fuel system.
- The filler neck on a TBI tank is 1-3/4" hose and the 1973 filler neck is 1-3/8" hose (one of the pictures below shows the size of the original hose printed on it for proof). The vent is also different; 5/8" versus 1/2". I was able to use a short length of the 1-5/8" hose on the filler neck and slip the larger 1-3/4" hose over it; kinda like how I've seen some radiator inlets done. I had to use a barb adapter for the vent line.
- The size of the fuel lines on a carb truck is different than a TBI truck.
- Feed line on both is 3/8"
- Return: TBI is 5/16" and carb is only 1/4"
- Vent: TBI is 1/4" and carb is larger 5/16".
- Before I started this project there were a couple of things I didn't know about the Pro-Flo 4, mostly things I had to purchase in addition to the kit.
- Need to purchase ignition coil
- Need to purchase fuel pressure regulator
- Throttle cable bracket; you may be able to make what you already have work, but in my case I needed something for the TH350 kickdown cable bracket.
- Problems with the factory accessory brackets, but in fairness that could have been an issue with any intake swap. The only other thing is the Pro-Flo adds further complication with the fuel rails.
- I follow instructions pretty carefully - I think this is a hold over from Navy machinist mate and nuclear power schooling. So I was surprised the installation instructions didn't include things that a typical Edelbrock intake install has; torque sequence and value for intake bolts. I found it even more ironic that I found the numbers by looking up the instruction sheet for an Edelbrock intake manifold. The instructions also didn't mention which hole to use in the throttle linkage for the trans kickdown. I had to use the instructions from the carb I removed to determine which hole to use.
- The instructions that came with my Pro-Flo 4 were not the most up to date version. I have attached the most recent version to this post, but if you're reading this several months from the posting date, you might check for another updated version.
- I also attached some more clarified distributor install instructions. I found them to be very helpful with putting the rotor in the right spot. When I started the engine, I didn't even need to move the distributor.
The last thing I want to say about the Pro-Flo 4 install is that @folkenheath was a great help getting this done. Most everything I needed for the install, including the Pro-Flo itself, I purchased from Heath. He went to a lot of effort to figure out what I would need for hoses, hose ends, adapters, fittings, and hose clamps. He also sold me the pump & regulator kit and the ignition coil. He gave me tips for what to use and answered a bunch of my emails. And on top of all that you can pay to have him add the Volcano upgrade to the intake.
If you are in need of a Pro-Flo 4, I highly recommend dropping a note to @folkenheath. He can get you Edelbrock items and anything under the Holley umbrella. And if you're interested in improving your intake manifold, check out his Volcano upgrade: https://volcanomanifolds.com
I'm not being paid for this post.
I just want to throw props to a CK5 vendor! 
If you are in need of a Pro-Flo 4, I highly recommend dropping a note to @folkenheath. He can get you Edelbrock items and anything under the Holley umbrella. And if you're interested in improving your intake manifold, check out his Volcano upgrade: https://volcanomanifolds.com
I'm not being paid for this post.
I just want to throw props to a CK5 vendor! 
Great info and looks good!
Big update!
Like Nick said great info for the next guy that wants to add the system to their engine.
Like Nick said great info for the next guy that wants to add the system to their engine.
Thanks for the write up and perfect timing. I'm thinking Santa might be bringing me a Pro Flo for my 53 Bel Air.
It was 46° when I drove today and it would not warm up above 154° while on the highway. When I got home I blocked off the rest of the grille. We'll see if that helps on tomorrow morning's commute.
What thermostat are you running?
Great writeup Scott, you did an excellent install, I hope you enjoy it for a long time. Did you get any videos of it running? What timing curve did you use?
And thank you for the great shoutout, I truly appreciate that! Glad I could help.
Also, I do wonder if your thermostat is stuck open? I'd put in a 180 Robert Shaw thermostat, the junk we get at the parts store frequently fails.
And thank you for the great shoutout, I truly appreciate that! Glad I could help.
Also, I do wonder if your thermostat is stuck open? I'd put in a 180 Robert Shaw thermostat, the junk we get at the parts store frequently fails.
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I have an EMP Stewart thermostat that's set for 180°. I'm thinking the big block radiator is too big, but I need to see how it works this summer with the AC going before I get excited about swapping it out. I always have to block the radiator for the winter in the crew cab, so I'm used to doing it. And I come up with something nicer than the cardboard - that was just the quick fix so I can get the Pro-Flo to learn.
You are welcome!
I haven't done anything with the timing curve, so it's whatever the default is. It seems good.
I have never had to block any radiator air flow. I am betting that your thermostat is bypassing too much. My '95 has a wide radiator in it, similar to the diesel one that you found. It still warms up and I can watch the temperature swing when the thermostat cracks open.
But if you aren't too worried,.
But if you aren't too worried,
.
This is the big block radiator for the 70's trucks. It's taller than the standard 350 radiator. They had 2 different heavy duty cooling radiators; a taller version that was usually in the big blocks and a "short" version that had 4 cores. I think mine had the short 4 core radiator from the factory because of the AC. I wonder if it would be better than the tall big block radiator in the winter time.
Blocking the grille is something I've had to do with any truck that I put a bigger radiator in. Had the same deal with the K5 because it had a 6.2L diesel when I bought it and I kept big radiator for the 350 I replaced the 6.2 with. The crew cab works great with a small section across the middle still open, but it looks like the C10 wants the entire grill blocked.
The other thing I noticed is I may have the electric fans coming on too soon. I saw they were on when the engine was still cool. The Derale PWM controller doesn't give you a number, you just adjust a screw until they come on when you want them too. So there's a lot of versatility, but you have to mess with them a few times to get them set where you want. Even if the grille is covered, the fans would be drawing air in.
Blocking the grille is something I've had to do with any truck that I put a bigger radiator in. Had the same deal with the K5 because it had a 6.2L diesel when I bought it and I kept big radiator for the 350 I replaced the 6.2 with. The crew cab works great with a small section across the middle still open, but it looks like the C10 wants the entire grill blocked.
The other thing I noticed is I may have the electric fans coming on too soon. I saw they were on when the engine was still cool. The Derale PWM controller doesn't give you a number, you just adjust a screw until they come on when you want them too. So there's a lot of versatility, but you have to mess with them a few times to get them set where you want. Even if the grille is covered, the fans would be drawing air in.
