Engine swap 318 to 360

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Justen newton

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Hello,
I have recently been researching an engine swap in a 1974 dart custom with the 318 and plan to switch to a 360. I know I have to have a suitable flex plate, and torque converter. Today I found the 360 and everything I need although it is in a 1 ton Dodge van. A few questions I have are the following; since it has the 1 ton 727 transmission, will it bolt straight to my 727 in my dart? Also since it being in a van will it bolt up to my engine mounts? Also, do I need a different wiring harness since it's in a van?? Any help would be highly appreciated thank you.
 
What year is the van? If you are lucky, and the 727 in the van is a non lock up transmission, and you have a 727 instead of a 904 in your Dart, all you need to do is move the torque converter from the Van 727 to the 727 in your Dart and that part is solved. Use your distributer from the 318 and all of your wiring in the Dart should work right back. Pay attention to the oil and temp sending units to see if they are the same between the 2 motors, and if they aren't and your gauges are working fine in the Dart, use the 318 sending units. You will need to get a 360 car oil pan and put it on before you drop the 360 in the Dart. Your existing motor mounts will work back, but you will need to add spacers such as flat washers to the drivers side mount, between the ears on the block and the motor mount bracket. Flat washers work just fine.
 
Why just why? You have stock in an oil company?
Is there actually something wrong with the 318 you have like a hole in the block?
 
check the oil pan fit also.. 318 pan won't fit on the 360..
 
need to modify the driver side 318 mount to work on the 360 or just buy the proper 340/360 mount.

screw the 727. assuming its an original 318 car it should have a 904. keep the 904 and converter and just get the proper flex plate.

you'll need a 360 car oil pan and pick up.

wiring will be the same. like already stated though check the senders and use the ones fro the 318 if the 360 ones are different.

its a pretty easy straight forward swap
 
JD pretty much nailed it. As everyone said you'll need a 360 car pan. Reuse the 318 pickup and dip stick.
I wouldn't use the 318 e-manifolds on the 360. Van center dump manifolds won't work in an A body
 
JDMopar said:
What year is the van? If you are lucky, and the 727 in the van is a non lock up transmission, and you have a 727 instead of a 904 in your Dart, all you need to do is move the torque converter from the Van 727 to the 727 in your Dart and that part is solved. Use your distributer from the 318 and all of your wiring in the Dart should work right back. Pay attention to the oil and temp sending units to see if they are the same between the 2 motors, and if they aren't and your gauges are working fine in the Dart, use the 318 sending units. You will need to get a 360 car oil pan and put it on before you drop the 360 in the Dart. Your existing motor mounts will work back, but you will need to add spacers such as flat washers to the drivers side mount, between the ears on the block and the motor mount bracket. Flat washers work just fine.
Click to expand...
The van is a 76'
abodyjoe said:
need to modify the driver side 318 mount to work on the 360 or just buy the proper 340/360 mount.

screw the 727. assuming its an original 318 car it should have a 904. keep the 904 and converter and just get the proper flex plate.

you'll need a 360 car oil pan and pick up.

wiring will be the same. like already stated though check the senders and use the ones fro the 318 if the 360 ones are different.

its a pretty easy straight forward swap
Click to expand...
So if I do have the 904 I can keep the 318 torque converter and just need a flex plate?
 
The heavier duty 727 and having the weighted converter are pluses. But more reasons against the 727 are that you won't have to change the driveshaft if you keep the 904, you know the condition of your existing trans and you won't have to mess with the trans linkage & cooler lines.

FWIW, does the 727 have a standard, long tailshaft? Some trucks had short tailshaft transmissions and 2-piece driveshafts. But I don't know if that applies to vans as well.

'76 is before lock-up converters.

Lock-up - non lock-up trans.jpg
 
JDMopar said:
What year is the van? If you are lucky, and the 727 in the van is a non lock up transmission, and you have a 727 instead of a 904 in your Dart, all you need to do is move the torque converter from the Van 727 to the 727 in your Dart and that part is solved. Use your distributer from the 318 and all of your wiring in the Dart should work right back. Pay attention to the oil and temp sending units to see if they are the same between the 2 motors, and if they aren't and your gauges are working fine in the Dart, use the 318 sending units. You will need to get a 360 car oil pan and put it on before you drop the 360 in the Dart. Your existing motor mounts will work back, but you will need to add spacers such as flat washers to the drivers side mount, between the ears on the block and the motor mount bracket. Flat washers work just fine.
Click to expand...
Yes 360 pan with the CORRECT oil pick up
 
Justen newton said:
The van is a 76'

So if I do have the 904 I can keep the 318 torque converter and just need a flex plate?
Click to expand...
Yep! I'll add a link below for the flex plate to do just that. @Locomotion posted a pic above that shows what the pan gaskets look like on 727's and 904's. Open your hood and look down to where the trans dip stick tube goes into the transmission. If that front passenger side corner of the trans is square, it's a 904. If it has a kick out in that corner, like the pic of the 727 pan gasket above, it's a 727. There is a B&M flex plate available either way. The one in the link below is for 360 to 904. Whichever one you get, hold it up to your torque converter like it will bolt up to the motor. B&M flex plates are marked 'Engine side'. Make all 4 flex plate to converter bolts line up and then mark both the flex plate and converter at one bolt hole. Line that one up first when you go to bolting them together in the car. If you don't do that step, you will make up new cuss words when you keep moving it to get it to line up....and it does it the 3rd time you move it....lol

All of your engine accessories will bolt back right where they were on the 318 and line up just like they did before. If the Dart has an electronic distributer, compare it to the one in the 360. If the plugs on the wires look the same, just use the 360 distributer instead of swapping them.

The things you will really need to mess with will be swapping the oil pan to a 360 car pan and pickup. Buy a new oil pump pickup with the pan. It ain't worth the trouble to pull the pan off the 318 to get that one when a new one is cheap. You will also need to get the throttle pressure (kickdown) linkage set correctly when you get your carb choice made. If you don't, your transmission won't live long.

It's great you're researching before diving in turning wrenches. Keep asking questions if you have them. :)

B&M Flexplate
 
If you use the van 727, the governor will be wrong.
If you change the rear gear ratio, and the governor is currently correct, then it will be wrong.
The TV pressure can be adjusted to compensate for just one ratio either way, but the result is not always acceptable.
This is a great swap; I've done it several times.
If nothing else, it allows an easy 10 to 20% less gear for similar take-off performance, and about one-half the percentage difference in fuel economy....... before the gear-change.
The 360 2bbl/Holley, if you reuse it, is a lil bigger than a Carter, but is usually calibrated very lean, and the transfer slot to mixture screw setting synchronization will be almost critical. This carb can be made to work, I mean it's just a carb, but it will take a lot of work for very little gain.
I have installed the factory 318 small-port intake and Carter carb with good success.
You will love the off-idle torque increase.
For low-rpm torque/ fuel economy, with a modest loss of top-end power,.... you can even use the 318 heads, and even the 318cam.
That factory cams are, IIRC;
240/248/112, compared to the 360 at
252/256/112
At split-overlap the Ica's are 50 for the 318, and 58 for the 360 2bbl cam.
That difference, at 8/1 true Scr is worth about 10 psi CCP(Cranking Cylinder Pressure), But a bigger gain is the Low rpm performance increase of 13.5%, from stall to about 3500 rpm, due just to the greater pressure.
Furthermore , the Power-stroke goes from 118 on the 360 to 122 on the 318. While just 4* difference, the 318 cam is calculated at split overlap=2* advanced whereas, the 360 cam at split-overlap is 112/straight-up, so there is room there for even greater results, by retiming the cam.
While just 4* different, it will still show up as better fuel-economy in steady state....... and with the higher cylinder pressure, lean-calibrated carb, and with proper cruise-timing, may/probably will get better fuel-economy everywhere, except possibly in town, which has lots of stop/starts, depending on your driving-style.
Like I said; I've had good success with the 318 top-end installed on the 360 short.
Either of these cams hardly care about headers, if the dual exhaust is free-flowing, with say 340, or Magnum log manifolds; but; Headers will NOT hurt it.
 
Last edited:
AJ/FormS said:
If you use the van 727, the governor will be wrong.
If you change the rear gear ratio, and the governor is currently correct, then it will be wrong.
The TV pressure can be adjusted to compensate for just one ratio either way, but the result is not always acceptable.
This is a great swap; I've done it several times.
If nothing else, it allows an easy 10 to 20% less gear for similar take-off performance, and about one-half the percentage difference in fuel economy....... before the gear-change.
The 360 2bbl/Holley, if you reuse it, is a lil bigger than a Carter, but is usually calibrated very lean, and the transfer slot to mixture screw setting synchronization will be almost critical. This carb can be made to work, I mean it's just a carb, but it will take a lot of work for very little gain.
I have installed the factory 318 small-port intake and Carter carb with good success.
You will love the off-idle torque increase.
For low-rpm torque/ fuel economy, with a modest loss of top-end power,.... you can even use the 318 heads, and even the 318cam.
That factory cams are, IIRC;
240/248/112, compared to the 360 at
252/256/112
At split-overlap the Ica's are 50 for the 318, and 58 for the 360 2bbl cam.
That difference, at 8/1 true Scr is worth about 10 psi CCP(Cranking Cylinder Pressure), But a bigger gain is the Low rpm performance increase of 13.5%, from stall to about 3500 rpm, due just to the greater pressure.
Furthermore , the Power-stroke goes from 118 on the 360 to 122 on the 318. While just 4* difference, the 318 cam is calculated at split overlap=2* advanced whereas, the 360 cam at split-overlap is 112/straight-up, so there is room there for even greater results, by retiming the cam.
While just 4* different, it will still show up as better fuel-economy in steady state....... and with the higher cylinder pressure, lean-calibrated carb, and with proper cruise-timing, may/probably will get better fuel-economy everywhere, except possibly in town, which has lots of stop/starts, depending on your driving-style.
Like I said; I've had good success with the 318 top-end installed on the 360 short.
Either of these cams hardly care about headers, if the dual exhaust is free-flowing, with say 340, or Magnum log manifolds; but; Headers will NOT hurt it.
Click to expand...
If you want to go slow and make less power than a stock 360, put a 318 carb, intake and heads on your 360...and don't forget to stick the 318 cam in there too. :realcrazy:
 
forphorty said:
If you want to go slow and make less power than a stock 360, put a 318 carb, intake and heads on your 360...and don't forget to stick the 318 cam in there too. :realcrazy:
Click to expand...
Show me in Post #1, where the OP says even one word about making more power?
Here, I'll help you ....
Justen newton said:
Hello,
I have recently been researching an engine swap in a 1974 dart custom with the 318 and plan to switch to a 360. I know I have to have a suitable flex plate, and torque converter. Today I found the 360 and everything I need although it is in a 1 ton Dodge van. A few questions I have are the following; since it has the 1 ton 727 transmission, will it bolt straight to my 727 in my dart? Also since it being in a van will it bolt up to my engine mounts? Also, do I need a different wiring harness since it's in a van?? Any help would be highly appreciated thank you.
Click to expand...
Notice what OP says; Then; Tell me how your post is; "help". Com'on man, how many conclusions did you assume?
Any help would be highly appreciated thank you.
Click to expand...
 
Upon further investigation and fender tag decoding, I have found I have the 904 torqueflite. Since the 360 is coming off the 727 do I need a 904 360 rated tc or can I just put a weighted plate on and call it good?
 
That kindov depends on how yur gonna drive it.
But hang on, 1974 is a long time ago. That car could have gone thru many transmissions since then, so as part of your detective work, did you actually slide under there and take a look at what might be there.....?
The stock 904 can easily be upgraded externally, to handle the stock 360. and can be modified internally, to live behind a typical street performance 360.
But to answer your question, the stock 360 needs ONE of two things;
1) either a Zero-balance Convertor PLUS a 360 weighted flexplate to fit whatever transmission is behind it..... or
2) a properly weighted-for-a-360 Convertor, to fit the trans.
 
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I'm not looking to be a street rod just something that has more sound and guts. Yes I know for sure it is the 904, if I don't want to hot rod can I just get the plate? Also what are the down sides to just getting the plate and nothing else?
 
AJ/FormS said:
Show me in Post #1, where the OP says even one word about making more power?
Here, I'll help you ....

Notice what OP says; Then; Tell me how your post is; "help". Com'on man, how many conclusions did you assume?
Click to expand...
You must have made some assumptions of your own, given the long detailed post. I only made one assumption . More power. Everyone I know who has replaced a smaller engine with a larger one has done it to get more power. My "help" :D
 
Justen newton said:
just something that has more sound and guts.
Click to expand...
Well. With a low-compression 360LA this is a tall order.
There is only one way to get the sound, which is with a bigger cam.
And, the bigger cam will make it's power several hundred rpm higher up in the rpm range, while trading away power at the lower rpm.
There are about three ways to overcome the low-rpm power-loss;
1) eliminate the lower rpm with a hi-stall convertor, or
2) increase the cylinder pressure, or
3) increase the remaining engine torque with TM (Torque-Multiplication), thru the gearing, or
4 ) some combination of all three.

In your case, having a 318, you already know what she feels like. so then, you can lose quite a bit of lo-rpm performance, before it starts to feel like a 318 again ..... but it will, with the wrong combination of parts.

If money is an issue for you, you will quite probably end up, disappointed.
If you can live without the big-cam sound, you will be much money ahead; just slap a "hi-stall Convertor" on her, and some performance rear gears, plus a 4bbl/dual-exhaust; and call it done.

Justen newton said:
I'm not looking to be a street rod just something that has more sound and guts. Yes I know for sure it is the 904, if I don't want to hot rod can I just get the plate? Also what are the down sides to just getting the plate and nothing else?
Click to expand...
Yes, you can get just the proper flex-plate. But I would at least install a shift kit, to deal with what you are already contemplating, as to "sound and guts".
 
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