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standup303

standup303

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I’ve been reading around on a 360 swap and have a few questions.

I have a 74 Dart Swinger Slant 6, my goal is to get a 360 in the car and running, then i can do a “build” down the road when more money comes in and get into new pistons, heads, etc.

My current trans is stamped A904, will this work with the 360? I read I would then not have a need to shorten my driveshaft. With the most popular trans are the 727 and 904, is mine that same 904?

Next question is, my plan is to throw a cam, then obviously header, exhaust, maybe bigger carb and intake. Would my stock 7.25 rear suffice or would I need to look for a 8.75? And would my 904/stock driveshaft work with that 8.75 rear?

Would I be able to install a floor mount B&M shifter with my 904 if I can use it? What does installing a floor mount shifter on a column shift car entail?

thanks in advance all!
 
Definitely go 8.75 once the Power comes alive! Putting a floor shifter in a column shift, is better than converting from a floor shift. You wouldn't have to cut the shifter mounts off. I think there's a way you can get a sleeve if you can't find a floor shifted column it'll actually get rid of the lug where your gear shifter is currently
 
Don’t rule out an 8.25” axle if you find one. Probably last a good while in front of the 360. Mine has anyway.
 
The 360 usually came with a 727 for small lock as well as the 340. They were externally balanced so you must use the correct flex plate/torque convertor or you will get a bad vibration.
 
Post up the following for the guys to recommend a cam for yeah.

style of use for the car ie Street/Strip or Road / Auto X
Compression ratio
Valve train with spring rate and heights
Intake
Ignition
Exhaust
Rear end gearing
Tire height
What transmission
car weight

This will help you to help the guys in helping you build your ride with less trial as there’s a few thousand years of experience here….
 
standup303 said:
I’ve been reading around on a 360 swap and have a few questions.

I have a 74 Dart Swinger Slant 6, my goal is to get a 360 in the car and running, then i can do a “build” down the road when more money comes in and get into new pistons, heads, etc.
Click to expand...

standup303 said:
My current trans is stamped A904, will this work with the 360? I read I would then not have a need to shorten my driveshaft. With the most popular trans are the 727 and 904, is mine that same 904?
Click to expand...
Yes. You have an A904, but yours is slant 6 specific. The slant 6, small block and big block all have different bellhousing patterns and their own separate transmissions. So you will need a small block transmission.

standup303 said:
Next question is, my plan is to throw a cam, then obviously header, exhaust, maybe bigger carb and intake. Would my stock 7.25 rear suffice or would I need to look for a 8.75? And would my 904/stock driveshaft work with that 8.75 rear?
Click to expand...

The 7.25 will probably live a little while, because likely what will happen is, you will obliterate the right rear tire, instead of breaking something. It's doubtful it will last a long time, so make plans. lol

standup303 said:
Would I be able to install a floor mount B&M shifter with my 904 if I can use it? What does installing a floor mount shifter on a column shift car entail?
Click to expand...
Of course. Just follow the deestruckshuns for whatever shifter you choose and we'll be here to help if you get stuck.

standup303 said:
thanks in advance all!
Click to expand...
Sho nuff.
 
I really haven’t been able to find a solid source for the swap all in one place. Can anyone recommend a site?

So I need a 360 magnum I plan on hopefully finding at a pull a part yard from a 92-03 Ram. Would the transmission with that engine I pull not work?

What years and models have the 727 that I could look at pulling? Or would it be best to find an individual transmission from Marketplace/Craigslist and get it rebuilt?

For the 8 3/4” rear, what models and years would I need for those? Looks like just A body Mopars with a V8? What is another good, more affordable source? I’ve been seeing those rears on eBay for $2k and up!
 
Truck-Magnums have dual mounting pads, but the truck bosses, I am told, will interfere with header selection.
Per a recent discussion here on FABO, 67 to 72 headers, and Schumacher adapter-mounts on a slanty-K, do Not play well together.
IMO;
Your best bet is to find a 73up V8 A-body or similar vintage chassis, and transfer all the required bits over from it. The LA family is not to be feared. If you are opening the engine up anyway, then the only advantage might be the roller-cam, which to me is relatively meaningless.
Your slanty, besides a cid deficit, mostly suffers from a lack of rear gear and stall. For a city-only type combo, this is easy to get around/overcome.
 
standup303 said:
I really haven’t been able to find a solid source for the swap all in one place. Can anyone recommend a site?

So I need a 360 magnum I plan on hopefully finding at a pull a part yard from a 92-03 Ram. Would the transmission with that engine I pull not work?

What years and models have the 727 that I could look at pulling? Or would it be best to find an individual transmission from Marketplace/Craigslist and get it rebuilt?

For the 8 3/4” rear, what models and years would I need for those? Looks like just A body Mopars with a V8? What is another good, more affordable source? I’ve been seeing those rears on eBay for $2k and up!
Click to expand...

The reason there’s no good compiled source for a magnum swap is because it’s not needed. Externally, it’s an LA small block with a serpentine setup and fuel injection.

Just look for a 68-76 small block K-frame. Keep an eye on the for sale sections here, there’s good deals to be had. I wouldn’t worry about the rear-end yet, a stock small block won’t destroy it immediately if you’re kind to it.
 
DNasty777 said:
The reason there’s no good compiled source for a magnum swap is because it’s not needed. Externally, it’s an LA small block with a serpentine setup and fuel injection.

Just look for a 68-76 small block K-frame. Keep an eye on the for sale sections here, there’s good deals to be had. I wouldn’t worry about the rear-end yet, a stock small block won’t destroy it immediately if you’re kind to it.
Click to expand...
I have a perfect rust free 67 to 72 K member
$250.
 
As to why you can’t use the magnum donor trans, well it depends. You can use it if you modify the torsion bar crossmember, but that’s getting in to fabrication territory. Magnum vehicles used overdrive transmissions that were based on the 904 and 727. Some were electronic lockup. As stated all these can be used but your looking at breaking out the zip wheel and welder, and also doing some electronic modifications depending on exact trans that comes with the magnum.
 
Hey man, welcome to FABO!

The Magnum is a great engine. Like others have said, you'll need to buy the K-member @GTX JOHN has for sale (lol).

I used my 273 engine mounts, just had to modify the passenger side mount.

If you keep the Magnum cam, you'll need an electric fuel pump. If you use a v-belt setup, you'll need a timing cover, water pump, and all pulleys from an LA.

The Magnum transmissions from 1990 - 1998 were called 46RH (H meaning hydraulic) and the 46RE (E for Electronic) from roughly 1995 - 2003 or 2004 in a late Magnum engine.

The 46RH is a relatively simple install, the 46RE you'll need all the Electronic stuff.

I swapped a 5.9 in place of a 273 so other than the passenger mount it was a drop in. Well, I had to grind some of the block to clear the power steering gear and had to grind some for mini starter clearance.

I went with v-belts. So I found a 1970 timing cover (Magnum engine has timing marks on the driver side, 273's were on the passenger side), my 273 water pump, alternator, power steering pump, fan and all pulleys. I used an Edelbrock Air Gap intake and Edelbrock 1906 carb. (Also did a cam and aluminum heads). Oh, and you'll need a car oil pan, the one from the Magnum won't work.

Post up any more questions.
 
Looking for a picture reminds me, if you go with v-belt you will need a harmonic balancer for an externally balanced engine and a flywheel for the Magnum engine (I just used the flywheel from my donor 2001 5.9. Here's a pic in work and finished.
IMG_20191124_213120.jpg

20201121_155440.jpg
 
AJ/FormS said:
Truck-Magnums have dual mounting pads, but the truck bosses, I am told, will interfere with header selection.
Per a recent discussion here on FABO, 67 to 72 headers, and Schumacher adapter-mounts on a slanty-K, do Not play well together.
IMO;
Your best bet is to find a 73up V8 A-body or similar vintage chassis, and transfer all the required bits over from it. The LA family is not to be feared. If you are opening the engine up anyway, then the only advantage might be the roller-cam, which to me is relatively meaningless.
Your slanty, besides a cid deficit, mostly suffers from a lack of rear gear and stall. For a city-only type combo, this is easy to get around/overcome.
Click to expand...
I have a 70 Dart slant 6 k member, Schumacher conversion mounts, 360 magnum, and Doug's D453 headers.
I'm guessing the discussion you referenced was using inexpensive headers that the steering linkage passes through. The only clearance issues for me are the tubes very close to the ps box, which I solved by raising the engine 1/2 inch on the driver's side. Yes, I realize quality control from the factory was poor, and that what fits one car may not fit another. I was under the impression that all 360 magnum's were "truck" , that is installed only in Jeeps, and pickup trucks ???
 
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