What upgrades

[DBZ Charger]

I have a 73 Charger SE with a 318. Wanting to go big block & have seen different views about what needs changed. I know the driveline will need to be upgraded but does the K frame ? I'm looking at either a stroked 400 or 440 with a automatic tranny. TIA

[303 Mopar]

K member will still work but with different engine mounts.  You will need new fuel lines, I would recommend adding a return line too which means new fuel sending unit. I would suggest bigger front sway and t-bars, your transmission or at least bell housing will need to change too.  You should swap your radiator to handle the bigger engine.  Not sure about your rear diff, but axles, gears, housing all need to be able to handle the high tq.  You should install subframe connectors.

[Mike DC]

                  
The K-frame confusion happens because it depends on the year.  

1972-earlier: same K-frame for small and big block (non-hemi) V8s.
1973-later: different K-frames between small & big V8s.  (hemi engines were extinct after '71.)


The whole front end changes pretty much EVERYTHING in 1973 because they added big rubber body bushings between the K-frame and unibody.  (And rubber layers on the leaf spring-to-axle clamps in back too.)  In the earlier cars the front K-frames are solid bolted like on a Dart/Duster/Valiant.  

The '72-73 front suspension change was the kind of thing you'd expect to happen when they do a total restyle.  It's unusual to see such a deep reworking of the chassis but the outer appearance is mostly the same.    

[VegasCharger]

.....1973-later: different K-frames between small & big V8s.....

You need to change the K frame if going from SB to BB or vise versa.

But Schumacher makes motor mounts that fits a 1973-74 B Body small blocks to fit a big block motor.

Here:

http://www.engine-swaps.com/Pages/ProductsYear/73UP.html#head2

[440]

I wonder how popular the swap down mounts are from 440 to 273 or 318.....

[Kern Dog]

I wonder how popular the swap down mounts are from 440 to 273 or 318.....

Probably as popular as Garlic flavored toothpaste or penis reduction surgery.

[JB400]

For someone wanting a better handling car, swapping to a smallblock wouldn't be a bad idea.

[VegasCharger]

I wonder how popular the swap down mounts are from 440 to 273 or 318.....

I could see a situation where someone had a 400 BB 2bbl wanting to go with a SB 340 in say like a '73 Satellite.

Agreed not a popular selling item though.

[krops cars]

I understand the whole big block thing. I had a 340 that would go. It was a great engine. durable and fast.