383/400 swap?

AL_Brad

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Has anyone compiled a list of what is needed to swap in a 383/400. Why not go a 440? I have access to a couple B motors in my play money price range. Can one of you point me to a YouTube where it's been done that would give me an idea... I thought ....motor/trans/b-body rear... but what about the radiator inlet/outlet, motor mounts, firewall clearance, trans mount, trans tunnel clearance... the "other" stuff.

Thanks
 

kkritsilas

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Keep in mind that the 440, is an "RB" (Raised B) family engine, which has a higher deck height than the "B" engine, which may have a hood clearance issue. And, Depending on the application, the 400 has the strongest blocks of any of the big block Mopar engines, with the possible exception of the "real" (i.e non-Gen 3) Hemi.
 

Aspen500

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For reference, the 440 (actually 500) in my Aspen. With a low rise intake, and 1/2" carb spacer, the air cleaner wing nut JUST sticks into the scoop opening.

Don't have enough time at the moment, but will try and answer some of your questions tomorrow.

20240326_194636.jpg


20240326_194623.jpg
 

AL_Brad

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Keep in mind that the 440, is an "RB" (Raised B) family engine, which has a higher deck height than the "B" engine, which may have a hood clearance issue. And, Depending on the application, the 400 has the strongest blocks of any of the big block Mopar engines, with the possible exception of the "real" (i.e non-Gen 3) Hemi.

Yep - I was basically answering that question with the subsequent reference to the motors I have access to. I read-up on the K-car brake booster and hood/other clearance issues for the RBs. I have been leaning toward the 400 as well. Thank you.

Thank you for the reply and offer Aspen. Very clean install!

I'm just daydreaming about passersby at the summer shows rubbernecking at the distributor sticking out of the front of the motor of the Imperial.... maybe paint it orange with a Magnum air cleaner housing disc...
 

Duke5A

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Motor mounts and exhaust are your biggest hurdles. The mounts are sold by Schumacher Creative Services at Engine swap solutions for your classic Dodge, Chrysler, Plymouth. Just follow the instructions as the K needs slight modifications. They sell headers too, but they're puny if max power is your goal. I ended up having to have a set made for my car. Oil pans and break boosters are easy to come by.
 

Reggie

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On the oil pan, I'll add that you need a "971" stamped oil pan and pickup to clear the frame. I had a 1968 440 "187" stamped pan that didn't clear. My 971 pan came from a 1976 Cordoba 400 but they were used on all 1973-up big block passenger cars. 440Source now sells the correct 971 pan, and mentions that it's good for F/J/M swaps. It's not cheap but it's probably worth it to get a pan that hasn't been beaten on and dinged up for the past 40 plus years.
Oil Pan - 971 Stamping - 73 & Later B Body - EXTRA THICK
 

AL_Brad

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How about the trans mounting? Anything needed extra for the 727s? Again, just constructing a shopping list.... thanks.
 

Reggie

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727 torque shaft support bracket (on right) is narrower than the 904 bracket (on left).
M-Body TS Brackets 727 on Left and 904 on Right.jpg
 
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Mikes5thAve

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Yes the bracket at the transmission is different for 727 and the last kick down rod is different also. Same with dipstick tube if it doesn't come with one.
 

Reggie

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You will also need to shorten your driveshaft as the 727 is longer that the 904. However, before you start measuring, you will want to swap in a stronger rear axle housing than the stock 7.25" unit. Forgot to mention that the older short style 727 TS bracket should work as well but my experience is with the later M-Body style bracket .
Older Style 727 Torque Shaft Brakets.jpg
 
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