I have a 56 C1-B8 pickup which I plan to mount the cab/box onto my modified 2001 Dakota chassis (4.7V8/5-spd, 2wd). I really want to build the engine with a 2008 or later reconditioned 4.7HO long block connected to a 65REF tranny. Get the 2008 or later 4.7HO long block and use most of the accessories of my 2001 4.7 engine. I will have to get a HO intake manifold and throttle body. My 2001 Dak already has Gibson headers on it I'll use on the new long block. So I assume I'll need the harness, PCM and TCM from a 2008 or newer 4.7? Or are there harness conversion kits that would allow my 2001 harness and other parts to work on the newer engine? And since my Dak has a NP3500 5-spd tranny means whatever harness connections there are to that tranny will not connect to the 65RFE tranny. Anyone with knowledge and experience doing that combination that wants to teach/guide my choices I'd certainly appreciate it.

www.hotwireauto.com I've used them before, real tech help if you need it. Not cheap, but what is these days?

Andy, you may want check these guys out. They don’t list a harness for your application, but they may be able to steer you in the right direction. I usually deal with Chris he’s always been helpful.

https://www.hotwireauto.com/chrysler-harnesses

Thanks everyone. Its great to have people who know what to do, and much more important, to find those willing to help.

With you talking about the 4.7L V8 I'm assuming when you are referring to an H.O version of the 4.7L I'm assuming you are referring the 4.7 you are referring to the second generation of the 4.7L V8. Just to let you know that is kind of a different beast. I know the cylinder heads are different where the 1st generation of the 4.7L version used one plug per cylinder the 2nd generation version used two plugs per cylinder like the 5.7L Hemi. Now, there was an older H.O. version of the based upon the 1st Generation of the 4.7L V8 that first showed up in WJ Jeeps in 2001 or 2002 I think it was and also 2005-2006 in the Dakota R/T. Part of the power increase for the "HO" with that engine was different camshafts and intake manifold (I think). Those require different valve springs and such. They're also used to be a company (no longer around) called KRC Performance that had custom grinds for the 4.7L V8 but, basically all those were was just a Crane version of the 4.7L camshafts.

The HO camshafts yielded fairly decent improvements in a standard run 4.7L V8. The other thing is that is mentioned is the 2008+ plus intake for the 4.7 which has different runners and even better runners than the 4.7L HO intake. The problem is you'll need an expensive adapter for the intake if you plan to run a cable driven throttle body from Air Ram Performance. I'm not sure what else you'll need for the swap but, I know that was the bigger thing. A Superchips Tuner (maybe even a Hemifever) version is another thing that helps I think. The camshafts and intake puts you close to what the newer 4.7L is assuming the standard tune is used on the later 08+ 4.7L V8.

Just going from memory, I think a Superchips Tuner will unlock another 50-55 horsepower from the 2nd generation 4.7L V8. The other thing about the newer 4.7L V8s and I'm not sure if this started around 2005 or so but, the 4.7L went to use an electronic throttle body where the older version still used a cable. Again, going from memory Chrysler at the time used a throttle cable driven throttle body until 2004 that I'm aware. After that I'm not sure. It use to be that you could buy a Fastman Throttle Body for the older 4.7Ls like yours but, I see he no longer offers them. The alternative being that you have a 2001 based engine is to use a 2004 throttle body. I think those might be 68mm where the 2001-2002 is either 62 or 65mm. My point is the last of the cable driven throttle bodies I believe offers the largest size. Again, I'm just going from memory. There used to be Underdrive Pulley for the 4.7L that was good for some power as well made by ASP I believe which again is no longer around.

Anyways, you'll need to figure out the electronics since the 2008 4.7L is a completely different beast compared to the older 2001 version. I hope this helps.

I agree with poorbody and Dabee on this and have seen them mentioned in other forums regarding these types of swaps.

i used those hotwire guys when my one buddy put a 96 LT1 into his 55 chevy.
their harness and computer re-do worked great in that car. plus, when we had any questions, they were easy to talk to and help us with anything we didn't understand.

Lots of great info, thanks everyone for taking the time. At least it gives me a list of questions for the long block supplier when I get to choosing the remanufactured long block to use with my Gibson headers. I know the larger throttle bodies for the 2008 and later 4.7V8 probably really help the engine breathing the most in the 4,000 rpm and higher revs. Perhaps the older slightly smaller throttle body still works as a smaller bore TB means the air velocity would be higher especially for the low to mid rev range of the engine. Generally, the higher airflow velocity at lower revs means the torque curve shifts to the lower revs. More research required.

I believe the 2008 up from what I vaguely saw yesterday use an electronic throttle body which means the computer controls the input more than your foot. The only thing I'll add is I hope the programming on the throttle body was corrected because the first versions of an electronic throttle used on the 2003 5.7L Hemis wasn't that great because the software wasn't that great even with the updates. There was a bit of a delay, so that's something you should keep in mind. You're 2001 Dakota will still use good old manual cable throttle control. My 2004 Ram did and throttle response off the line was always better than I experienced with two 5.7L Hemi trucks.

Yup. My 2001 Dakota 4.7 has the throttle cable controlled TB. But my plan is to use the 4.7HO long block, which means I'll need to buy a used 4.7HO intake manifold, the Airtek adapter, and maybe a used TB from a pre 2008 4.7HO engine, like out of a Jeep.

I recently saw a youtube video of a guy walking through a salvage yard and checking pre-2008 4.7 engines, where he found a bunch had failed/cracked a cast post in the head. From the top side of the head on the front cylinder passenger side, there is a cast post in the head that supports the rocker arm for the valves. He pointed out that post is known to crack/fail such that the rocker arm assembly drops out of position, which then of course fails the valves for that cylinder.

The post 2008 head on that side, cylinder #2, has that post cast into the head with a thick web from top to bottom of the post, so the post cannot crack off and cause the rocker assembly to drop out. Just based on that info I will only buy a remanned 4.7HO that has the updated head casting to support that rocker assembly.

https://www.youtube.com/watch?v=H6I8Ake2dcE

With that update, and the other updates done to the 2008 and later 4.7, and the updates that Powertrain does to the remanned long blocks they produce, it should make for a much better, reliable long term 4.7HO engine. I keep up on my oil changes and maintenance, so I feel the 4.7HO can be a good engine.

I have a 4.7 in a 12 reg cab long bed 1500 2wd. It's supposed to be a 10:1 310hp engine but sure doesn't seem like it. (That's oem stock specs for that engine and year. Hasn't been modded.
Driving that truck it sure doesn't seem that powerful. That's supposedly the highest HP engine I have ever had. It sure don't stem like it. The 360 in my 01 Durango sure seems to have more in it than this 4.7.
This is the first 4.7 I have ever had.
And I only got that because the 318/360 can't be had no more and I needed something new enough to qualify for a vehicle loan since I don't have the cash I can lay my hands on.

The horsepower doesn't mean squat in a truck or heavy street driven vehicle. It is all about torque, and the 360 has it in spades over the 4.7. If you built a 10 to 1 magnum 360 it would be an even bigger difference.

And torque really applies depending on where it is in the power curve and rpm range.

The 360 V8 has stock HP of 255 at 4,400 rpm. The torque is 360 ft-lb at 2,400 rpm

The 4.7HO V8 has stock HP of 310 at 5,000 rpm. The torque is 329 ft-lb at 3,950 rpm.

THAT's really where and why you feel the power of the 360 versus the 4.7HO. The 360 has more torque for sure, but LOTS more torque 1,550 rpm sooner than it does for less torque in the 4.7HO. Given that much difference in torque SO much lower in the rev range, I'd bet the 4.7HO has less than half the 360 torque at 2,400 rpm.

Which now has me thinking, tuned 360 with EFI for my 56 versus the 4.7HO? The 360 makes SO much more torque at lower revs that the 4.7HO cant even match at higher revs. A crate 360 from Powertrain is about $2500, while a 4.7HO from Powertrain is $4300. I had thought of using all the engine accessories off my 2001 4.7 for the 4.7HO to save money. But for $1800 I can buy a LOT of 360 upgrades and get even more HP and Torque. I wonder though what a strong tuned 360 with EFI loafing along the highway at 2,000 rpm would get for fuel mileage? Could a 360 with a bit of a tune for power, headers, EFI, Magnaflo exhaust and connected to a 66RFE trans with the 0.62 2nd overdrive get into the mid-20's at 75mph on east flat terrain? Torque really does the work and I like an engine that doesn't have to rev over 5,000 to make all the power I'd ever need.

I've had a lot of 360s, gas mileage is not one of their strong suits. My experience with a 360 is 2-3 mpg lower then a 318 in the same vehicle and the same drivetrain and fuel distribution system. I have never driven a 4.7, but the many people I've talked with tell me their gas mileage isn't as good as a 318 either. .

Next, that 56 Dodge pickup isn't exactly designed to slip through the air. I believe mid 20s mpg is a pipe dream with any motor in that truck unless you plan to keep it under 60 mph always. High teens, maybe 20 mpg is doable, much more then that I'd be surprised, and I don't think those numbers would come from a 360.

My 49 with the 5.2 Magnum, efi 46RE, with 3:55 gears, 235 x 75 x 15 tires, and a soft bed cover is getting near 17 mpg @ 70mph. It is a 4x4, so I would expect a 2wd to add a couple mpg at the same speed Drop the speed to 60 and the mpg jumps up.

Older trucks are certainly not as aerodynamic as the current trucks. Things like flush side glass and no drip rails, and smoother blended surfaces all combine to make a newer truck more slippery. But in frontal area, the barn door effect is pretty equal. Think of shining a bright light straight at the front end onto a bright surface behind the truck, the shadow outlines the total frontal area. The older truck, especially a lowered truck, likely presents a smaller/lower frontal area than many of the newer trucks.

I'll have to compare the overall package of a 4.7HO versus a crate 318/5.2 Magnum versus a crate 360/5.9 Magnum.

FWIW, I had a mild 360 in my 87 Diplomat that replaced it's 318. On the highway, with the same drive train (A833) otherwise and 2.94 gears, the 318 would get ~25 mpg driving it like Miss Daisy was aboard. The 360 got ~20.

The 360 was more fun though.

My 55 Dodge truck with the 5.7 gets 19 mpg on the highway running 75 mph. Don’t know what daily average is as I always have my foot in it.

You would want to be starting with a 360 Magnum if you want to realize that goal IMHO.

The Magnum combustion chamber is more efficient than the LA chamber and requires less timing. Less timing to burn the same air/fuel charge means less pumping losses which will translate into more power WFO and less fuel consumption at cruise/part throttle.

A custom roller cam is a drop in and if chosen wisely, should get you where you want to be +/- .

If I was looking for that last MPG I would be looking at a 5 or 6 speed manual.

Kevin

Right, the Magnum combustion chamber is much better than the LA. That is why the 360 style Magnum heads, on the 318 block, with improved intake and exhaust can make real usable daily driver power. So the 360 Magnum heads, with Keith Black pistons which flush out to the deck, raise the 318 compression ration near to 10:1, even better than the 360 Magnum. The stock 318 block, even in the 5.2 Magnum has the pistons max stroke height in the bore below the deck. By using pistons flush to the deck at TDC the real gains of the swirl effect in the Magnum heads help make the power. Team that up with an Edlebrock air gap intake and long tube headers and it makes for a strong every engine that is still reasonable to live with in a daily driver.

I'm getting lazy, and even though I like the manual trans in my 2001 Dakota, I want to set up my 56 with an automatic so my wife can drive it. Part of the deal of me spending the bucks to build this truck is so she can drive it and enjoy it also. When I retire June of 2024 I'll turn in my company car and then a nice pickup truck will be my daily driver. But I cannot justify spending $35,000+ for a used current truck when I can build a great vintage daily driver for less than $20,000. So with some careful choices, a 5-spd or 6-spd automatic with a .67 to 1 or even .62 to 1 overdrive with torque converter lock up can be very efficient on the highway. Again, torque in the 2000 to 4000 rpm range helps so the tranny isn't trying to shift around to maintain the speed I set on the cruise control.