gas or diesel super duty truck for 12v swap

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moparguy55

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Pondering buying a superduty for a 12v swap. I'd be using the 12v, nv4500 and dodge T case. Thought a gas superduty that was manual would be cheaper to start with. Got thinking the brake set up between a gas and diesel ford must be different ? Would you use the cummins vacuum pump to feed the vacuum for the brakes on a diesel ford truck ? I'm assuming a SD gas job you'd need to change the brake set up to a ford diesel anyway right ?

For wiring I believe I'd need to run a toggle for the grid heaters,hot wire to the starter. Could I just use a manual cable for the fuel shut off solenoid ?

Thanks guys
 
You can run a manual cable for the shutdown solenoid, but why.... its so easy to wire up the right way. As for the grids, a momentary toggle or push button would be easiest if the truck was originally gas, if it was a PSD to start then just get a heavy duty relay and use the wire that signaled the glow plug relay to run it. Wiring up the starter is a matter of hooking up the main cable, and one for the solenoid.

If you use a Dodge alternator, you will need to convert it to an internally regulated setup, which is cheaply done at a starter/alt rebuild shop. Or look at PA Performance for getting a heavy duty internally regulated alt. that will bolt right up.

Superduty diesel brakes are hydroboost, they use pressure from the power steering pump for assist, no vacuum needed for the brakes. You could swap it all over from a diesel setup, or just run vacuum assist brakes.

Is there emissions testing in your state/county?

If so, buying a diesel SD will be easier than getting a gas and converting it to diesel as far as registering and emissions stuff is concerned.
 
Thanks for all the useful info. There is no emissions tests here in quebec canada. As for registration, I'd leave it the way it was on the registration. They are worried about tax dollar collecting, if the vehicule's engine is larger than 4L you pay an extra 150 in licensing fees each year. Either way they'd be getting the extra $150 whether its a 5.4/6.8/PSD. I'm sure taking the badges off they wouldn't have a clue.

One question when you say just run vacuum assisted brakes could i run a vacuum line from the cummins vacuum pump to the gas brake booster ?

For the glow plug system on the ford trucks, isn't there a sensor that tells the ecm how cold the engine is and the glow length is based on the engine temp ? With this sensor gone due to the 12v and the ford ecm still in place how would the ecm send power to that hot wire to the relay ? and how long would it send power to the grids ?
 
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moparguy55 said:
One question when you say just run vacuum assisted brakes could i run a vacuum line from the cummins vacuum pump to the gas brake booster ?

For the glow plug system on the ford trucks, isn't there a sensor that tells the ecm how cold the engine is and the glow length is based on the engine temp ? With this sensor gone due to the 12v and the ford ecm still in place how would the ecm send power to that hot wire to the relay ? and how long would it send power to the grids ?
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Yep, hook the Cummins vacuum pump to the brake booster. You will also have to tee in to the vacuum line going to the cab for HVAC controls, but this is very easy.

I can't give you a 100% definitive answer, but in my truck (99 F350, formerly PSD, now 12V) the Wait To Start light still comes on for a while. I honestly never pay attention to how long it stays on depending on ambient temp., but it does seem that it stays on longer when the truck is cold, and when air temps are cold as well. I dont pay attention because my grids are not hooked up. I have not had any issues with cold starts. If it is bitterly cold, my truck is plugged in anyway so it was never a concern, but I may hook them up someday....just because they are there.

I am sure someone could give you a better answer, but this is what I think you need...

OEM air intake temp sensor (which you would have from a diesel truck)
OEM coolant temp sensor
OEM oil temp sensor (possibly, I am not 100% sure on this)

I know the ECM looks at several factors for the length of glow plug heating, but it also defaults to a certain time when these factors are missing.

Then just find the signal wire going to the glow plug relay, and run it to your new grid heater relays. If you are thinking of using a generic relay for the grids, make sure it is rated for AT LEAST 90 amps continuous. I think I remember reading that each grid heater draws almost 90 amps.
 
just hook the grid heater to starter signal wire as well as the white wire for the fuel shutoff
i prefer the diesel models
ive done conversions on 1980-98 f350s 99 and up 97 chevy 3500 and a 4bt in a ranger
 
fordimca22 said:
just hook the grid heater to starter signal wire as well as the white wire for the fuel shutoff
i prefer the diesel models
ive done conversions on 1980-98 f350s 99 and up 97 chevy 3500 and a 4bt in a ranger
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If you hook the grid heaters to the starter signal wire won't the grids only be on for as long as the truck is cranking? If so, that is basically no time for the grids to be on, assuming the truck is tuned/maintained properly.
 
Once again Thanks for the info.
I think I'd prefer a V10 and just run the cummins vac pump to the booster and vents. I believe the rad in the v10 is the same as a diesel. For the fuel shut off I'd try to wire it up, but good to know worse comes to worse I can use a manual cable. Grids I'd need them up here in Quebec in the winter. Seems once it gets below frreing down to say 25F the 10 second cycle in my 97 is just right it fires right up. once its down in the single digits, or below i cycle them twice and away we go.

Are the differentials on the diesel superdutys beefier than the gas jobs ? With a gas job would it be better to just get the intercooler set up from a dodge too ? I know the piping on my buddies 04 harley looks nothing like the intercooler piping on my 97.
 
moparguy55 said:
For the fuel shut off I'd try to wire it up, but good to know worse comes to worse I can use a manual cable. QUOTE]


i would wire up the solenoid. its easy to do. i have a diagram i drew up for it on my computer somewhere. pretty sure i posted it somewhere on here too.
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moparguy55 said:
Once again Thanks for the info.
I think I'd prefer a V10 and just run the cummins vac pump to the booster and vents. I believe the rad in the v10 is the same as a diesel. For the fuel shut off I'd try to wire it up, but good to know worse comes to worse I can use a manual cable. Grids I'd need them up here in Quebec in the winter. Seems once it gets below frreing down to say 25F the 10 second cycle in my 97 is just right it fires right up. once its down in the single digits, or below i cycle them twice and away we go.

Are the differentials on the diesel superdutys beefier than the gas jobs ? With a gas job would it be better to just get the intercooler set up from a dodge too ? I know the piping on my buddies 04 harley looks nothing like the intercooler piping on my 97.
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Not so sure that the radiators are the same.... but they might be. Axles are basically the same across the board (as far as SRW trucks are concerned) but 99-01 F250s had a D50 front, while the F350s had a D60. After 01, all trucks had D60 fronts. Rear axles were all same for SRWs which was a 10.5" Sterling, DRW trucks got the D80. I may have my years messed up, it might be 99-02, maybe someone can confirm the years.

I would try and get a Ford intercooler. It will mount up much more easily, and with a $100 kit of mandrel bent 3" tubing from somewhere like Columbia River Mandrel Bends you can get factory looking intercooler pipes.
 
Texascaddy Did you use the 12v exhaust manifold or is a special fordcumms.com style manifold required ? Did you use a Ford Turbo down pipe ?


The steering and suspension on the 250/350 99-03 super dutys are all solid axle leaf spring no more IFS front like the OBS trucks right ?

The 04 and up superdutys went to coilover like the 2nd generation dodge ?

I think that would cover the last of my questions. Have a pretty good idea now of what direction to go. Thanks to you guys on compdiesel :clap:
 
I put a 12v in my gas superduty and the rad is more than the cummins needs i run a full sheet of carboard in front of it in the winter and no fan and it still dosent get up to temp. and the rearend is a 10.5 its held up to abuse for 2 years so far and no problems.
 
ozone burner said:
I put a 12v in my gas superduty and the rad is more than the cummins needs i run a full sheet of carboard in front of it in the winter and no fan and it still dosent get up to temp. and the rearend is a 10.5 its held up to abuse for 2 years so far and no problems.
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Did you just run the vaccum from the pump to run your brakes ?
 
moparguy55 said:
Texascaddy Did you use the 12v exhaust manifold or is a special fordcumms.com style manifold required ? Did you use a Ford Turbo down pipe ?


The steering and suspension on the 250/350 99-03 super dutys are all solid axle leaf spring no more IFS front like the OBS trucks right ?

The 04 and up superdutys went to coilover like the 2nd generation dodge ?

I think that would cover the last of my questions. Have a pretty good idea now of what direction to go. Thanks to you guys on compdiesel :clap:
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I run a 2nd gen Dodge manifold, flipped upside down. If I had to do it over again I would think about a 3rd gen style manifold which tucks the turbo close to the motor, down low. However I don't think a 3rd gen manifold will work without some porting work. Turbo to HVAC clearance becomes a real issue when running a flipped 2nd gen manifold.

As far as the downpipe, I started with some 45 elbows, a flange and some straight pipe and made my own. I am not sure of a downpipe out there that is premade, too many variables I think.

F250 and up are all straight axle. 05 was the switch to coils, from 99-04 it was leaf. No more IFS.
 
ozone burner said:
I put a 12v in my gas superduty and the rad is more than the cummins needs i run a full sheet of carboard in front of it in the winter and no fan and it still dosent get up to temp. and the rearend is a 10.5 its held up to abuse for 2 years so far and no problems.
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Do you do much towing with your truck? The only reason I ask is because the gas radiator (if it is different) may not be able to keep up with the Cummins when the motor is being worked hard for prolonged periods of time.

Depending on what intentions the original poster has for the truck, he may need the largest radiator possible.
 
ozone burner said:
I put a 12v in my gas superduty and the rad is more than the cummins needs i run a full sheet of carboard in front of it in the winter and no fan and it still dosent get up to temp. and the rearend is a 10.5 its held up to abuse for 2 years so far and no problems.
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Does it still have the gas guage cluster in it ? If so I believe the temp range on the gas motor would be higher than the diesel.

With the big cummins rad in my 97 ram it runs up to 1/2 then drops down 20 or so degrees when it cycles. I heard in the fords the v10 has the same rad as the diesel. Was your truck a v8 or 10 ?
 
My parts sources all look like the V10 and diesel rads are the same. I wouldn't worry too much about the temperature range, since Ford gauges are basically idiot lights, I would use the OEM sensors just to keep the dash happy, and also run a set of good aftermarket gauges for oil pressure and water temp.
 
texascadillac42 said:
My parts sources all look like the V10 and diesel rads are the same. I wouldn't worry too much about the temperature range, since Ford gauges are basically idiot lights, I would use the OEM sensors just to keep the dash happy, and also run a set of good aftermarket gauges for oil pressure and water temp.
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Did you guys get an adapter to get the crank sensor signal to the factory ford tach and is it anywhere near right or better off with a small autometer diesel tach ?
 
I'm using a tach sensor out of a 93 Ford with a 7.3 IDI. It is the kit that Ford Cummins sells. You have to grind 2 more notches in the Cummins harmonic balancer. It seems to work just fine.
 
texascadillac42 said:
I'm using a tach sensor out of a 93 Ford with a 7.3 IDI. It is the kit that Ford Cummins sells. You have to grind 2 more notches in the Cummins harmonic balancer. It seems to work just fine.
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Man you should write a book on the Super duty swap :)
 
i just ran my brakes off of the vac on the engine they work better then they did from the factory and as for the rad i pull a gooseneckand it still runs cold you can tell when the thermostat opens on the gauge and in the winter its no were near that and in the summer i have a electric fan and the only time it runs is when i am in stop and go
 
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