273 or 225?

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Well, since you are not concerned about originality, I would go the 5.9 route because you will spend a lot more money trying to get the results of a stock 5.9 out of the 273. The other route would be something like a turbo /6 and that isn't cheap either.
 
I think the main issue that a person needs to know about a /6 before deciding to hop one up is the limitation of the head. Unported you'll be lucky to make 200 hp I bet a good chunk less.
Now if your willing to port 1 hp per cid is in reach, they can do 250-300+ NA HP but more than likely most won't and be more street strip/race engine. Now if that's ok build away.
 
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How easy would the 273 to 318 swap be? Any modifications to the body/frame at all? Also lets keep in touch about the hood.
Save the motor mounts, V8 steering center link, exhaust manifolds, gas pedal and throttle cable assembly. The only body modification you might have to make is notching the torsion bar crossmember on the passenger side if you want true dual exhaust. You can do dual exhaust without doing that, but the pipe hangs lower to get under the crossmember. Find a later 904/998/999 and your driveshaft will work right back. You might have to modify your existing shift linkage from the slant trans. One more thing to watch for if you swap to a later 318 and use the 65 exhaust manifolds. Mock up the drivers side manifold to the motor before you put it in the car. The early A drivers side manifold will hit a bump on the bottom of the later heads. It's a danged if you do, danged if you don't situation. If you grind the slightest bit too much on the head bump, you hit water. If you try to tighten it without good clearance, you will crack the manifold. It's fixable with conservative grinding and double gaskets, or no grinding and a spacer between the manifold and head. Good luck with it!

:thumbsup:
 
How easy would the 273 to 318 swap be? Any modifications to the body/frame at all? Also lets keep in touch about the hood.
You can use the same motor mounts as the 273, BUT-
318s (both LA and Magnum) have a larger crankshaft counterbore than the 273- which means you'd need to have a spacer bushing made (or buy- but I'm not aware of any current sources) in order to properly fit the '65 torque convertor. Or alternately, have a custom TC built.
There may also be issues with exhaust manifold fitment on later ('73 and up?) 318s and Magnums, the driver's side manifold interferes with part of the head. But that's a whole different thread.
 
Interesting,where does a 340 stand on your list?
2nd, I have one all but done on an engine stand. Having run almost all Mopar engines in a 4 speed car. Keep in mind I am a street high performance everyday driver. I want performance and mpg as I would, and still do, drive from the east coast to South Dakota and Nebraska on a yearly basis. We are talking 12 to 15 hours of straight driving at a constant 70 - 80 mph per day for two days. The 66 Barracuda does not make that run anymore, but has in the past. Always nice to get low to mid 20's mpg and a good 273 is almost as quick as a 340 the way I build them. The 273 and the 340 are similar with the heavy duty parts like forged cranks, bushed rods, and floating pistons. The pistons in both are close to zero deck and I love a solid lifter cam, which comes stock in a 273.
 
It’s $1000 for a clapped out wagon that hasn’t run in years. I get your affinity for the 273, but for that same money he could have more horsepower, and an engine designed to run on todays nonleaded fuel. What if the bearings are shot, or cracked heads with sunk seats? The junk yard will give you 30 days to bring any motor you buy back. Will the stranger on market place do the same if the 273/904 is shot?

I always assume the engine is shot, but rebuildable, I prefer untouched engines anyway. I have fixed, if possible, too many "rebuilt" engines. 273's were pretty much bulletproof unless run without oil or coolant, unlike newer engines where cracked heads are more than common. I have never had any valves sink, but I usually replace the exhaust valves with stainless steel ones as my common practice. Usually 273's are cheap to rebuild except for pistons, but good pistons for a 318 are not cheap either. I am not sure I would pay $1,000 for a parts car, but a V8 in an early A is a pretty sweet deal to get all the early A V8 special parts. The 904 is probably fine, you can tell by the fluid. You can also drain the torque convertor and adjust the bands in the older transmissions and have them last virtually forever.
 
I always assume the engine is shot, but rebuildable, I prefer untouched engines anyway. I have fixed, if possible, too many "rebuilt" engines. 273's were pretty much bulletproof unless run without oil or coolant, unlike newer engines where cracked heads are more than common. I have never had any valves sink, but I usually replace the exhaust valves with stainless steel ones as my common practice. Usually 273's are cheap to rebuild except for pistons, but good pistons for a 318 are not cheap either. I am not sure I would pay $1,000 for a parts car, but a V8 in an early A is a pretty sweet deal to get all the early A V8 special parts. The 904 is probably fine, you can tell by the fluid. You can also drain the torque convertor and adjust the bands in the older transmissions and have them last virtually forever.
And if it’s and buts were candy and nuts, we’d all have a merry Christmas.
 
All my motors are good in the garage. You think any used motor is a sure thing? LOL!
Not at all, but my local pick and pull gives you 30 days to inspect and return a motor if it’s junk. You ain’t getting that from marketplace.
 
@tandart66 can you clarify what rebuild your 66 dart means? Are you doing a full restoration, or focusing on certain areas as issues present themselves?

I replaced the 225 in my 65 dart with a 273 last year. After 4 years of collecting parts. Still didn’t drive much this year because of life stuff, but also some mechanical things that I want to address (rebuilding transmission like I should have in the first place, focusing on suspension and steering, and replacing rotted floors, etc.). The answer to the questions above may help folks respond too.
 
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I trust my experience, but I am not there. I am not the OP, it is his decision. I have one 318 Magnum, but will probably never be built. I did like your offer to help the OP. The whole donor car is a huge plus to me if doing that swap.
 
@tandart66 can you clarify what rebuild your 66 dart means? Are you doing a full restoration, or focusing on certain areas as issues present themselves?

I replaced the 225 in my 65 dart with a 273 last year. After 4 years of collecting parts. Still didn’t drive much this year because of life stuff, but some mechanical things that I want to address (like now I’m focused on suspension and steering, and replacing rotted floors, etc.). The answer to the questions above may help folks respond too.
I guess just getting the car running and really working on it down the road/as issues arise. The car itself is in great shape, just the 225 seized up, I bought a new slant core for 50$ and intended to hot rod it out a little, and get some power out of it. But now that this deal has presented itself I think the v8 route would be more satisfactory for me.
 
I trust my experience, but I am not there. I am not the OP, it is his decision. I have one 318 Magnum, but will probably never be built. I did like your offer to help the OP. The whole donor car is a huge plus to me if doing that swap.
I ain’t trying to pick on you, but your love for the 273 clouds your judgement. It’s a great motor, but not the best option for this situation.

The car is a total rust bucket with years of back fees at the DMV. $1000 for a clapped out 273 and cable shifted 904 just isn’t worth it in our area. Junk yards full of 318’s with a guarantee(you can buy an additional 12 month warranty too) and marketplace/Craigslist is full of v8 904’s for cheap or free.

If it don’t make dollars, it don’t make sense.

IMG_5401.png
 
I guess just getting the car running and really working on it down the road/as issues arise. The car itself is in great shape, just the 225 seized up, I bought a new slant core for 50$ and intended to hot rod it out a little, and get some power out of it. But now that this deal has presented itself I think the v8 route would be more satisfactory for me.

What kind of mechanical abilities do you have? Have you ever done a motor swap, or transmission repair/adjustment?
 
I have never done any sort of motor swap or transmission repair before, but I do have some buddies that have alot more experience that are willing to help.
No better car to learn to work on than a slant 6 A body. Swap the seized 225 for the 225 you bought for $50, and get it running. It will be a great feeling of accomplishment, and you will get a chance to see whats involved in replacing the motor. Then you can tell that story for the rest of your life.


If you are dead set on a V8 swap, I’d still advise against the 65 wagon unless you can get it for $500 or less. It’s got $$$ in back fees and then you need to pull everything and recondition. Unless you want to swap in a clapped out grease pit.

How’s the rest of the car? Brakes and suspension good?
 
I ain’t trying to pick on you, but your love for the 273 clouds your judgement. It’s a great motor, but not the best option for this situation.

The car is a total rust bucket with years of back fees at the DMV. $1000 for a clapped out 273 and cable shifted 904 just isn’t worth it in our area. Junk yards full of 318’s with a guarantee(you can buy an additional 12 month warranty too) and marketplace/Craigslist is full of v8 904’s for cheap or free.

If it don’t make dollars, it don’t make sense.

That looks great. I'd do that in a heartbeat, looks unmolested. Been doing this stuff all my adult life. ALL the stuff to do a V8 transplant in a 66 dart, starting with a complete 273 drive train. I mean everything is there. Plus wagon rear springs and torsion bars. I could care less about which engine. A good 273 has so many sweet parts. Never would I swap that 273 for a 318.
 
That looks great. I'd do that in a heartbeat, looks unmolested. Been doing this stuff all my adult life. ALL the stuff to do a V8 transplant in a 66 dart, starting with a complete 273 drive train. I mean everything is there. Plus wagon rear springs and torsion bars. I could care less about which engine. A good 273 has so many sweet parts. Never would I swap that 273 for a 318.
This kid had never don’t a motor swap or even maintenance on a transmission. He is not you and you are being arrogant on this topic.

Proud Early A Owner
 
No better car to learn to work on than a slant 6 A body. Swap the seized 225 for the 225 you bought for $50, and get it running. It will be a great feeling of accomplishment, and you will get a chance to see whats involved in replacing the motor. Then you can tell that story for the rest of your life.


If you are dead set on a V8 swap, I’d still advise against the 65 wagon unless you can get it for $500 or less. It’s got $$$ in back fees and then you need to pull everything and recondition. Unless you want to swap in a clapped out grease pit.

How’s the rest of the car? Brakes and suspension good?
The rest of the car is in its stock condition, I figure whether I keep the slant or not im gonna get beefier brakes an torsions bars at some point.
 
This kid had never don’t a motor swap or even maintenance on a transmission. He is not you and you are being arrogant on this topic.

Proud Early A Owner
I'm not being arrogant, have you had or done an early A. It takes more than a motor. Just because I prefer one motor over another does not matter, it is my opinion. We all started where he is now. If one wanted to swap a V8 for a /6, the best advice I could give, is to get a donor car. Early A V8 cars and all that goes with it are hard to find in todays world. 318's have never been hard to find. They run forever and usually outlast the body. An Early A has more than a few peculiarities and some things special to them. It's not about you.
 
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Hey all,

Im trying to rebuild my ‘66 Dart and have came to yet another dilemma. My recent intentions were to rebuild the stock slant in the car, and try to hot rod it out a little bit, but now a new opportunity has risen. I found a ‘65 with a 273 that I could use as a parts car to make the swap to a v8. Is it worth the extra time and money to v8 swap the Dart or should I continue with the slant build? Any ideas would be greatly appreciated.
(2 1965 Barracudas, /6 vs 273.) I had the same path you are faced with. I went with the /6, which is still an ongoing project. The engine is ready to be installed and run. Head and block work, cam (Hughes), intake (Offy 4 barrel), headers (Clifford), N2O, etc. If I were to start over...I would finish the car first, up to the point of installing the engine and making it a "roller." Right now, my project car is still on the rotisserie, not quite ready to be on the ground. In the meantime, my ready to run "hot rod /6," has been on the stand over a year. It seems (IMHO) everyone does a small block or something else. I want mine to be kind of unique, thus the /6 (which is a matching #) for this car. The 273 is the same for the other car, matching #. if you choose, swapping out a /6 for a 273 it's not a real big deal. However, I elected to go from a 904 A/T to a 833 4S which has been giving me some headaches. My 273 car had a three speed in it and the project car was an A/T. Some of the linkage and stuff works, some of it does not.
Norm
 
Good guitar work 3R ! you slants sounds awesome too.

For the OP, if it were me and I was spending money to rebuild regardless I’d do the v-8. If doing an 8 get these essential stuff from the donor car and then maybe consider more cubes too
 
Okay, if I'm reading this right, your proposed donor Dart is a wagon- Therefore you can't use the ball and trunnion driveshaft in your '66, since the wagon is built on the Plymouth 106" wheelbase and your Dart is a 111" wheelbase. The shaft will be too short- You'll need to have a new one built, if you're lucky enough to find a shop that will still do B&T shafts. There is a way to build a conversion shaft for the B&T trans., but we can cross that bridge later if you go that route.
 
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