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440 vs 340

aussiemark

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A 318 to 340 swap is no comparison to a small block to big block swap. That would be just unbolt one and bolt in the other. Going to a big block changes a whole lot more.
There are nearly the same amount of parts needed to be changed for the 318 to 340 as the RB swap (if done properly) in most cases lets say you have a small radiator and you want the 727 rather then the 904 plus you still have to change one of the mount adapters and 340's have better suspension unless this was optioned in the 318 car. The exhaust will need to be changed to dual with different manifolds to suit the big port 340 heads. and if your car has a 7 1/4 rear axle you will need an 8 3/4. So you will need a transmission, driveshaft, radiator, torsion bars, rear springs, 1 x engine mount adaptor, exhaust system, rear axle and the accelerator cable brackets and kick down linkage so in reality the only other things you would need to change to fit an RB or B engine would be an engine wiring harness and 1 x extra engine mount adaptor. My car has a 26" radiator as part of the air conditioning package, a 3.23 sure grip 8 3/4 axle, S13 suspension and I will strengthen the 904 to handle the extra torque. My car will not need as many changes but not many 318 cars have these options fitted so going RB is not that much harder. Put the 440 in and have some fun with it rather the sell it at a loss and build another engine.
 
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Cuda525

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No Worries on the swap been through it before. Also suppliers have come along way in listing what’s compatible with each other.,
 

Cudakiller70

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What about using the 440 with an auto? Max torque for tire roasting, auto for cruising. Can change back no problems.
 

Cuda525

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I’m looking in to transmissions right now and going to pass on the totemic for awhile. A&A,TCI,B&M??
3:55 gear
 

hellrats

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I've done the swap many times. From a 318 to a 340 is nothing. You can use just about every part except one motor mount. Event the 904 will hold up fine behind a 340. Many more parts are need to go to a big block.
 

hellrats

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Your do not need a transmission, radiator, linkage, or torsion bars ect. The 340 will work with all of that from the 318. It will bolt right in and you can use everything except one motor mount. For that you can use the 318 bracket and weld the missing ear on it so it will work on the 340 block as well. Headers and exhaust and your done. You have to play the throttle linkage game a bit going form the 2 barrel to the 4 barrel but it will work too. Not so with a big block swap.
 
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aussiemark

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Should be easy to drop the 440 in being a 340 car it will have the S13 suspension, 26"radiator and 8 3/4 rear axle (should be fine with a Torqueflite) I have seen water pump housings with the spout on the opposite side maybe look into that rather then modifying the radiator tank (if need be). If the firewall wiring plug is the same as the 70-71 grab a 440 engine wiring harness from Year One and leave the original one with the 340?
 

Cuda525

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I agree,have 489 diff, 26” radiator bought a WP housing for hose position on of the small block. Went as much aluminum as possible should weigh close to 340, also will paint an AAR hood body color and install should be a wash. I took car over a scale 3400 right now, will check after swap
 

hellrats

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Transmission won't fit. Big block is a different bolt pattern.
 

Cuda525

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Yes, will build a different one wanted to shelf the numbers matching trans anyway.
Is the drive shaft the same?
 

aussiemark

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Tried to check the driveshaft length in the 1970 factory service manual but the 340 isn't listed so can't compare. How badly was the other car damaged in the fire? I am building a 440 with as much aluminium as possible as well for a V code car got a pair of Mopar Performance aluminium heads, aluminium water pump & housing and will swap the cast iron 6 pack manifold for a 69 A12 aluminium version be silly to use it with the aluminium heads anyway will paint it Hemi orange so it looks stock same with the heads.
 

aussiemark

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The 340's S13 suspension should work well with the aluminiumised 440 but you may need the Hemi rear springs to stop it changing lanes when you step on it.
 

hellrats

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Your driveshaft should work if you stay with an automatic
 

hellrats

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Rear springs would be a plus with a big block that's for sure
 

Cuda525

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Changing lanes hands free !!
Take that self driving cars:steering:
 
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