318 & 904 to 383 & 727 conversion

Postby 1340 » 30 Jan 2006 5:39

Hi there, I'm brand spanking new to this board, but I've already had so much help with stuff from reading other posts, its really great. Anyways, my situation is I have a stock 1970 challenger 318. I have a 383 and 727 that i wanna throw in, but it seems like the 727 is longer than the 904, or is it just me? (Hard to tell, the 904 is in my car and the 727 is on the garage floor but it seems longer). Anywho, I'm a young guy who hasn't done an engine swap before but I'm eager to get this big block in there. I understand I don't need to change the k-frame, and I have the motor mounts for the engine already. Is it a direct bolt in, or is there anything I don't know about. I have heard its an easy swap but I just don't want to tear the 318 out and then find out I missed something. Thanks a lot! Also, what can I reuse off of my 318 block on the 383. Should I get a new radiator and fan? I think i have a 50amp alternator because the 318 has a/c (double pulley) so that isnt the 37 amp right? Thanks for any help I can get, and major :thumbsup: to this board Its awesome. Gotta love them e-bodies
1340
 

Postby dave-r » 30 Jan 2006 8:48

Yes the 727 is longer. You either need to find the shorter 340 or big block Challenger driveshaft or you need to get your existing shalt shortened. Any decent driveshaft place will do that for you. Just measusure the length you need VERY CAREFULLY!

You may need the big 26 inch radiator. Depends how hot the 383 runs.

Otherwise the swap is straight forward.

Think about fitting thicker front suspension torsion bars for the heavier engine. And a front and rear sway bay to round off the package.
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