Getting ready to pull my 340 and replace with 5.7
Considering doing this from bottom, what are the steps needed to get this done.
Background:
70 Challenger, 340, 518
Will be doing this in garage, so height clearance isn't great.
Does the rear need to be on jack stands?
Tires need to come off, or will it roll out all together?
Planning on leaving the trans in car and just removing engine.

Any and all info appreciated

Thx

All the pictures and videos where this is being done the trans and engine are bolted together. If you leave the transmission in place you have to figure out how to support it as well.

Also need to make sure the engine picker legs and wheels stay clear of the engine cart.

Rear wheels can be left on the car and on the ground.

Couple YouTube videos on it out there to help see it in action. Here is one with the body still on caster wheels in the back.

https://youtu.be/8HHQqGnU5DQ

You disconnect all the usual stuff, plus disconnect the coupler of the steering shaft from the steering box, remove the front shocks, remove the torsion bars, uncouple the lower ball joint studs from the spindles. It works nice to build some kind of cart on caster wheels with some supports on it that will hold up the K frame and the transmission. Lower the car enough that the K frame and the transmission are sitting on the cart. Take out the 4 K frame bolts, remove the transmission cross member, then lift the body off of the engine / transmission / k-frame assembly.
What you lift it with depends on your situation. I like to do it with the car on the hoist so that I can safely and easily lift the body. If you don't have a hoist, I think it's going to be a lot harder. You need to get the car up in the air pretty high. If I didn't have a hoist, I think I'd pull it out from the top. I think it would be a lot easier.

This is how the factory did it.

It is very easy to do from the bottom.

Good info and video, I'll add this is going to be only me doing this by myself.
I bought the HF 2T lift, but it looks like way more stuff needs to be disassembled and put back together when going in from bottom.
Seems to be perfect for a car under going a full resto.
I don't mind the extra work if that makes sense, just worried getting everything aligned from bottom might be tougher compared to dropping in from top, if I'm doing this alone?

I also don't see buying a dolly for an engine/trans combo, unless maybe a couple of HF wooden types could work.

Thx

I have seen several wooden bucks that guys built themselves. Just make sure you have good casters that will hold the weight.
And get the height close for the buck. I would suggest you measure from the ground up to the longitudinals where the k frame attaches and mimic that on the buck.
For the trans you may want to raise or lower that with a floor jack to get the cross member in.

It is a the right way to do it but it requires a bunch more equipment and space. Doesn't sound like you're set up for it.

I did that install myself in a 2 car garage. The engine trans dolly was an old toolbox frame with an added cross member. Quite simple and uneventful. I have done it this way on A bodies also. I also built my own run stand.

You're probably right, underneath seems great if the car is already apart.
It looks like the valance and bumper would also need to be removed at a minimum. No to mention the steering, K-frame, separating ball joints, torsion bars, etc........................
And then I'd have to build/buy some sort of brackets for lifting.

I have a big shop and an overhead crane so the job is easy for me. I just lift the car with the overhead crane and then roll the engine and trans underneath. Then I pull the engine into place and bolt on the suspension while the car is up in the air.

That's the hard way of doing it. Most just unbolt the UCA inner pivots, disconnect the steering coupler, unwire it, remove the radiator and hoses, take out the four K member bolts and drop it out on the K member. How you lift the body varies depending on what you have to lift with but a couple of extensions mounted to where the bumper brackets bolt up and lifting with those can do the trick.

Nice car and shop, Andy.

No need to take the front valence or bumper off. I use a homemade jig to lift the car with my engine hoist and the rear end on jack stands. The jig has to bolts welded at either end that fit into one of the factory holes in the bottom of the frame, so the jig can't slip out of position. The jig goes between the frame rails approximately where the radiator goes.I don't have to remove the hood either. I do have to remove the rear valance to lower my exhaust.

To roll the engine/trans out from under the car, I use a simple furniture dolly. The nice thing about doing it this way is that the headers and accessory drives can be assembled while the powertrain is out of the car. I did pull my transmission first, so I would not have to bleed my hydraulic throwout bearing.

This time I separated the lower ball joints and left the discs, shocks and upper control arms in place on the car. I usually work alone on my stuff, and am careful to use good safety practices to avoid injury.

Anything engine related on any of my 3 cars goes out the bottom...

Rear wheels on the ground...

Engine crane with a bracket similar to the one posted above that drops in once the radiator is removed...

Unbolt everything up top...

Lift the car up on to jack stands...
remove driveshaft...
loosen but leave in place the 4 bolts for the trans crossmember...
separate collectors from headers...
separate lower ball joints leaving all brakes...spindle and rotor together and tie up into wheelwell...
remove torsion bars and steering column shaft from box...

I then raise the car up and put my dolly in under the engine and transmission...

Lower the car down and remove the 4 K frame bolts and the 4 trans crossmember bolts...

Lift the car up and then roll the engine and trans out with the K frame...headers...starter and everything else attached...

Lower the car back down onto the jack stands until its time to repeat the process in the opposite order...

Same for the 69 Dart...

I built a tricycle caster setup for the engine and transmission and then I made a bracket for my transmission jack to hold the K frame and suspension. These were both super simple tools for me to build but I'm set up with some basic fab equipment as well as a welder. Not everyone has the tools to build the tools.

in all my years of replacing engines, i never once took one out the bottom.
you guys almost have me convinced to do that when i finally get around to swapping the engine in my charger.
however, i'm afraid of "mission creep", deciding i need/want to do more things to it, and the car has been down way too long as it is, and i ain't getting any younger !
i can fab up just about any tool or fixture i may need for any repair or modification of any item.

From the bottom install is a good choice if you have done a whole restoration as it allows you to get a whole bunch of stuff up under there at once while minimizing paint damage.

If you have a running and driving car and just need to get the engine out (only) it may be faster to go out from the top as your not messing with the suspension etc. You can just stack some wood under the trans to hold it in place while the engine is removed.

Don’t need a big shop. Both these Hemi stuffed in an A-body were done in a two car garage. 1st a Dart, then a Barracuda….

I elevate the rear tires about 6-8 inches off the ground; use nylon tie-down straps (big not small) and hook the front bumper backets. i then lift the body with a cherry picker. The engine/trans and K-frame sit on furniture dollies. Sooo much easier than in through the top and with fewer scratches to the fire wall.