Author Topic: Engine Swap  (Read 746 times)

Offline pkorpi

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Engine Swap
« on: November 07, 2013 - 01:40:51 PM »
So my 340 decided to take a dump on me....I don't have the money right now to do a complete rebuild, so I found a cheap 318 around town and plan on bolting it in while I rebuild the 340 (may take me a few months to years to finish). From what I've researched the 318 should bolt right in....?? The plan is to swap the motors in 2 weeks. Anyone have any good advice for the swap? Prior to the swap? Easier to pull tranny with the motor?

Car is a 72 Challenger that was originally a 318, but was swapped out for a 340. The 318 is coming out of a A body. Both cars have the 904 transmission.

Any advise is welcome!

Thanks!  ;D





Offline burdar

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Re: Engine Swap
« Reply #1 on: November 07, 2013 - 01:55:37 PM »
It will bolt right in.  Take the hood off the car before you start.  You might be able to get the engine changed with it still in place but I'd just remove it.  Pull the engine out the top and leave the trans in the car.  Your 340 exhaust manifolds and engine mounts will bolt right up to the 318.  Depending on what brackets and pulleys come with the new engine, you could swap over all that stuff too. 

This is a very simple swap.  It can be done in a weekend easy.

Offline Chryco Psycho

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Re: Engine Swap
« Reply #2 on: November 07, 2013 - 02:01:02 PM »
the left engine mount is different between 318/340

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Offline pkorpi

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Re: Engine Swap
« Reply #3 on: November 12, 2013 - 10:42:27 PM »
Is this the spacer needed for the left motor mount to work?

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Offline Chryco Psycho

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Re: Engine Swap
« Reply #4 on: November 12, 2013 - 10:48:47 PM »
the picture is just  the motor mount , the ears on 340/360 blocks are thicker so the mount is different by 1/4" or so

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Offline pkorpi

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Re: Engine Swap
« Reply #5 on: November 12, 2013 - 10:56:24 PM »
Anyway I can just put in a washer or something similar to make up the 1/4" difference? Or would it just make more sense to just get a new mount?

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Offline pkorpi

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Re: Engine Swap
« Reply #6 on: November 12, 2013 - 11:02:27 PM »
These should work?

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Offline Chryco Psycho

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Re: Engine Swap
« Reply #7 on: November 12, 2013 - 11:07:55 PM »
those are the mounts , the first ones were A body I think
the difference is the bracket on the block & it is not the thickness but the forward to rear positioning , so the tailshaft of the trans will be about 1.5 off to one side using the 318 mount , I don't believe you can shim it as the 318 earon the block is thinner so the new braket has to be tinner to line everything up correctly

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Offline Topcat

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Re: Engine Swap
« Reply #8 on: November 12, 2013 - 11:15:50 PM »
Anyway I can just put in a washer or something similar to make up the 1/4" difference? Or would it just make more sense to just get a new mount?

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When I had my 340, that's what I did. I couldn't find an original 340 mount.
It did work and I didn't have any driveshaft angle problems.
Tried hard to find the right mount.
Mike, Fremont, CA.


Offline pkorpi

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Re: Engine Swap
« Reply #9 on: November 23, 2013 - 08:03:09 PM »
Got the engine in today. Ran into an issue tho. The water pump pulley is hitting the crank pulley. Has anyone ran into this issue? If so what did you end up doing? Thanks.

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Offline burdar

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Re: Engine Swap
« Reply #10 on: November 24, 2013 - 12:17:43 AM »
If the pulleys hit, they aren't a matched set.