74 challenger, original 318 car, currently 340, starting 440 swap

[A3404bbl]

New member, I have a 74 challenger that was an original 318 car. It currently has a 340, and I am just starting the build on a 440 to swap in. Any advice, or tips and tricks from fellow members that have completed a 440 swap is greatly appreciated!

 

[Rapidfire]

Welcome to FEBO! Greetings from Nebraska!

 

[fasjac]

Welcome to the site from Arkansas! Nice looking challenger
I’ve done the type swap on my 73 cuda 3 speed. When I bought the car in the early 80’s the 340 was long gone. If I could have found the original block, I would have put all back original. Fast forward, couldn’t find the motor so I built a 440. Piece of cake. Fits right in the k-member. If you’re going to run headers, I recommend TTI. remember that the engine harness will need to be modified a bit or buy one for a big block. I changed to hemi torsion bars and HD rear leaf springs.
3.91 sure grip rear. Have fun with the torque monster!

 

[Chryco Psycho]

Welcome to the site & nice project !
What help do you need ?
I agree with above , not sure what you plan to use for a trans but the small block trans will not fit the big block but are a number of options .

 

[A3404bbl]

Welcome to FEBO! Greetings from Nebraska!

Thanks! Looking forward to learning from people and showing the progress on my project.

 

[A3404bbl]

Welcome to the site from Arkansas! Nice looking challenger
I’ve done the type swap on my 73 cuda 3 speed. When I bought the car in the early 80’s the 340 was long gone. If I could have found the original block, I would have put all back original. Fast forward, couldn’t find the motor so I built a 440. Piece of cake. Fits right in the k-member. If you’re going to run headers, I recommend TTI. remember that the engine harness will need to be modified a bit or buy one for a big block. I changed to hemi torsion bars and HD rear leaf springs.
3.91 sure grip rear. Have fun with the torque monster!

Thanks for the info! What modifications did you have to make for the harness? Since a big block wasn’t available in ‘74, I haven’t been able to locate a new harness.

 

[A3404bbl]

Welcome to the site & nice project !
What help do you need ?
I agree with above , not sure what you plan to use for a trans but the small block trans will not fit the big block but are a number of options .

I recently replaced the trans in the car with a new Street Rodder 727 from TCI. I spoke with a rep at smr motorsports that said they make an adapter plate to mate the TCI small block 727 to the 440. That is the current plan.

 

[Chryco Psycho]

Mostly just extending wires to the front of the engine to reach the coil & distributor etc is what needs to be changed .
You could have all of the 727 internals swapped into a big block case also , internally all 727s are the same I would rather pay to do that than use an adapter .

 

[NoCar340]

Mostly just extending wires to the front of the engine to reach the coil & distributor etc is what needs to be changed .
You could have all of the 727 internals swapped into a big block case also , internally all 727s are the same I would rather pay to do that than use an adapter .

Agreed on both, especially the latter. Adapters are just adding cost, complexity, and potential problems. All you need is a big-block 727 case and everything from your new trans will swap straight into it. Any transmission shop should be able to pull it off. I'd pay more labor than the cost of the adapter to avoid the adapter, to be honest.

On using your existing harness, you can purchase a Hopkins 47965 or Curt 58020 two-pin harness and lengthen that, making the distributor plug and play on both ends--assuming you still have your original electronic ignition. That way, the only modifications needed on the car's harness are those that run to the coil, either 2 or 3 depending on whether you have a tach.

Other snafus, or potential ones:

• Your accessory drives/brackets and distributor will not work on the 440.
• Depending on the 340 you've got and the 440 you're getting, the torque converter might not be properly balanced. If both are internally balanced (steel cranks) you're golden.
• Depending on what you've got for exhaust, 340 pipes won't connect to 440 headers or manifolds, so expect at least some exhaust work, minor with headers.
• The outlet on your radiator (lower nipple) is on the wrong side, if your 440's water pump housing is '72 or older. You can either use the '73 and newer pump housing (which will require '73-newer brackets and pulleys--they're different) or have your outlet swapped to the driver's side by a radiator shop.
• You will need new kickdown linkage from a 440, not a 400 or 383.
• You'll need a new throttle cable for a four-barrel big block.

On the bright side, your starter, alternator, and power steering pump can be reused, once you have the right brackets. Your transmission cooler lines should fit fine. Even the cap and rotor are the same, but you'll obviously need new wires... someone done put the distributor on the wrong end of one of those engines.

 

[NoCar340]

Oh, yeah... welcome aboard. We're glad you're here!

 

[fasjac]

Thanks for the info! What modifications did you have to make for the harness? Since a big block wasn’t available in ‘74, I haven’t been able to locate a new harness.

I bought a big block harness for mine because mine was rough anyway. You should be able to just lengthen the harness to the distributor, coil etc. it’s really pretty straight forward if you’re using the factory control box and distributor.

 

[fasjac]

Agreed on both, especially the latter. Adapters are just adding cost, complexity, and potential problems. All you need is a big-block 727 case and everything from your new trans will swap straight into it. Any transmission shop should be able to pull it off. I'd pay more labor than the cost of the adapter to avoid the adapter, to be honest.

On using your existing harness, you can purchase a Hopkins 47965 or Curt 58020 two-pin harness and lengthen that, making the distributor plug and play on both ends--assuming you still have your original electronic ignition. That way, the only modifications needed on the car's harness are those that run to the coil, either 2 or 3 depending on whether you have a tach.

Other snafus, or potential ones:

• Your accessory drives/brackets and distributor will not work on the 440.
• Depending on the 340 you've got and the 440 you're getting, the torque converter might not be properly balanced. If both are internally balanced (steel cranks) you're golden.
• Depending on what you've got for exhaust, 340 pipes won't connect to 440 headers or manifolds, so expect at least some exhaust work, minor with headers.
• The outlet on your radiator (lower nipple) is on the wrong side, if your 440's water pump housing is '72 or older. You can either use the '73 and newer pump housing (which will require '73-newer brackets and pulleys--they're different) or have your outlet swapped to the driver's side by a radiator shop.
• You will need new kickdown linkage from a 440, not a 400 or 383.
• You'll need a new throttle cable for a four-barrel big block.

On the bright side, your starter, alternator, and power steering pump can be reused, once you have the right brackets. Your transmission cooler lines should fit fine. Even the cap and rotor are the same, but you'll obviously need new wires... someone done put the distributor on the wrong end of one of those engines.

Lol

 

[moparlee]

Welcome to the site from Michigan!
Already you have gotten some excellent tips . As you already have seen, there is a lot of knowledge here to help you with your engine swap.