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Discussion Starter #1
I am in the process of swapping a VE pumped 6BT into my 1989 ford that had a 460. I was hoping someone could help me with the wiring.

Mostly the Tach, is the factory tach controlled by the ECM or just from a signal from the coil? What would be the best way to get the factory tach to work?

Also, cruise control. Will the cruise control work without the engine ECM? Or does the cruise control have its own control module? The speedo is cable drive, so it seems that as long as that works then the cruise should work. Thoughts?

thanks, Aaron
 

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There are several questions that pop up. What transmission do you have? Is it 2wd or 4wd? I believe the cruise control on those years reads off the transmisssion unless it's 4wd. Then it gets its reading from the transfer case. There is a vacuum servo unit under the hood that receives the signal from a speed control module behind the dash which operates the throtle. You will need a vacuum pump of some kind to operate that and the ac/heater controls. If you keep the vacuum boosted brakes you'll need it for that too. If you change to a hydroboost brake system this wouldn't need a vacuum source. As for the tach I have been searching some of my wiring diagrams but just haven't come up with an answer. Dakota Digital makes tach interfaces that will help. It would be neat to find an instrument cluster for a diesel of the same vintage and swap gauges. Then your fuel guage would say "Diesel Fuel Only" and you'd have a diesel tach. You could leave the speedo alone. I'm doing a 90 F250 but mine was originally diesel. Much easier change over. I plan to use a 21si alternator which has an output for the tach and the charge light on the dash. If your truck is auto trans then you're going to have to think about reworking it for different shift points. Gas and diesel transmissions aren't the same. If you have the ZF 5 speed you are better off to some extent. Either way you will need an adapter plate to join the engine to the transmission. Destroked has the best and they are $795. If you have the manual trans then add about $650 more for a flywheel and clutch assembly, depending on where you get it. I got mine from Valair which was about the most reasonable I could find. South Bend has excellent clutches but their's was over $1000. There are several builds on the forum that have been this route. Hopefully they can help more than I.
 

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Discussion Starter #3
Thanks for the response, it answers my question on the cruise. I found the same dakota digital and am thinking that is about the only option right now.

I am using the dodge automatic transmission A518, it is 4wd, so I am using the NP205 t-case. The speedo cable does have some sort of electronic plug on it, must be the cruise signal.

The engine has a vacuum pump for the brakes, hvac and cruise.

thanks again for the response.
 

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I believe the A518 is a gas engine transmission. The diesels used an A618 which was beefed up to handle the torque of the 5.9. Also had different shift points for the lower reving engine. Your Ford spedo is all mechanical. Won't use an electronic signal from the transmission. Just a plain old cable drive like they used for years. I am sure there are adapters out there.
 

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Discussion Starter #5
There are gas and diesel versions of the A518, diesel A518 doesn't have lock up torque converter, just over drive. The A618 (aka 47rh) has OD plus lock up torque converter.

The speedo is mechanical, but there is an electrical plug on the end where it goes into the t-case, must be for the cruise control?
 

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Discussion Starter #6
finally have enough posts to post links, yay!

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This weekend I finally got the cummins to fit in the engine bay of the CC. The firewall is different between the 83 and the 89. The 89 comes forward about an inch further. So the engine needs to move forward 1.75". Will modify the engine mount adapters and it will bolt right in using the 460 isolators, and the 6.9L diesel cross member adapters.
 

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If you move the engine forward you wont have room for the fan to fit behind the radiator in the stock location, Just "massage" the firewall with a sledge hammer to make room for the rear valve cover. There is nothing behind the dash in that area to disturb. I massaged mine back about 2"
 

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Discussion Starter #9
I was worried about fitting the radiator in the stock location, so last night I set the core support in place and put the radiator in place, and I have probably 1.5" between the fan blade and the radiator. Seems like this is plenty of room? FYI I am using a 1st gen dodge radiator as it is larger than the 460 radiator.

I have already "massaged" the firewall with the sledge hammer, in its current location I need to do a little more massaging so I can R&R the rear valve cover without lifting the body. haha

It sucks that the engine is 2" off center to the passenger side, looks like the ford engine cross-member is designed this way. That forces me to move the radiator to the passenger side also. It looks like everything should fit fairly easily, including the PS intercooler.
 

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finally have enough posts to post links, yay!

donor:

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This weekend I finally got the cummins to fit in the engine bay of the CC. The firewall is different between the 83 and the 89. The 89 comes forward about an inch further. So the engine needs to move forward 1.75". Will modify the engine mount adapters and it will bolt right in using the 460 isolators, and the 6.9L diesel cross member adapters.
Any update?

I am especially interested in what you ended up doing regarding motor mounts.

Roy
 
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