273 -318 swap information needed

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I have a 1965 barracuda I am new to the A bodies I would like to replace the 273 and a 904 with a 318 I’m looking for any suggestions and information and things to look out for.
 
not sure what you need to know...
acquire 318

remove 273

install 318

pretty much a straight swap
 
welcome! If your 273 is original, the water pump will be cast and exit on the opposite side as a '70 and up 318. Also, the timing marks will be on the opposite side. A few ways around it, one being a different radiator. I swapped out a '65 273 with a '85 318. I used the 273 torque converter behind the 318 and it worked great.
 
welcome! If your 273 is original, the water pump will be cast and exit on the opposite side as a '70 and up 318. Also, the timing marks will be on the opposite side. A few ways around it, one being a different radiator.
yup, or you can swap over your old or same style water pump / timing cover. that way all the brackets you have will fit. if you change to a 70' later WP, getting the matching timing cover and accessory brackets will be a big help
 
Looking for what 318’s will work what won’t any mods needed or adapting to the 904
all 318's will bolt up and work with the 904. when you find one, then you can figure out what that one specifically needs
 
welcome! If your 273 is original, the water pump will be cast and exit on the opposite side as a '70 and up 318. Also, the timing marks will be on the opposite side. A few ways around it, one being a different radiator. I swapped out a '65 273 with a '85 318. I used the 273 torque converter behind the 318 and it worked great.
Thank you
 
yup, or you can swap over your old or same style water pump / timing cover. that way all the brackets you have will fit. if you change to a 70' later WP, getting the matching timing cover and accessory brackets will be a big help
Thank you
 
Depends on what you are doing "with" the transmission. You using a later transmission or the original in the car? I think the converter snout "changed" in 68? You used to be able to buy an adapter/ bushing that went over the small early converter and into the larger/ later 318/360/340 crank to use the old trans in the newer engine
 
If you want to use the early water pump / timing cover setup on the later engine, you may? run into trouble with the later balancer, which is required for the 318. IE the timing marks will need to be redone, and the balancer may? be larger diameter I'm not sure. You would have to fabricate a different timing pointer which is not that difficult. Also if the 318 balancer is thicker front to rear, the original 273 pulley stack may have to be shimmed at the water pump, and possibly at the alternator. Again, not very difficult
 
Depends on what you are doing "with" the transmission. You using a later transmission or the original in the car? I think the converter snout "changed" in 68? You used to be able to buy an adapter/ bushing that went over the small early converter and into the larger/ later 318/360/340 crank to use the old trans in the newer engine
I would like to use original transmission
 
Ah yes - the use of the later crankshaft motor would be facilitated by use of the aforementioned adapter, another consideration when looking at what transmission to use is the early shift linkage (shift cable and park cable) will not work with later transmissions. It's a pain in the butt to find a modified stall speed torque converter for the early 904 (later ones have a different spline count) AND the front universal joint is different. If you are going to change to a later 904, it is a good idea to change everything all at once. Me? - I found someone to modify my torque converter and am using all early stuff - works great! (I did freshen up the transmission and put in a shift kit) and I have put a much modified 318 (350 + horsepower) in front of that setup with no problems.

Cheeh14/Art (RT)

btw - does anyone know who is making those crankshaft adapters? I made mine, but don't work in a machine shop any more! Thanks Art(RT)
 
Ah yes - the use of the later crankshaft motor would be facilitated by use of the aforementioned adapter, another consideration when looking at what transmission to use is the early shift linkage (shift cable and park cable) will not work with later transmissions. It's a pain in the butt to find a modified stall speed torque converter for the early 904 (later ones have a different spline count) AND the front universal joint is different. If you are going to change to a later 904, it is a good idea to change everything all at once. Me? - I found someone to modify my torque converter and am using all early stuff - works great! (I did freshen up the transmission and put in a shift kit) and I have put a much modified 318 (350 + horsepower) in front of that setup with no problems.

Cheeh14/Art (RT)

btw - does anyone know who is making those crankshaft adapters? I made mine, but don't work in a machine shop any more! Thanks Art(RT)
I guess one could just use a newer transmission and get a floor shifter and a newer drive shaft along with the newer 318.
 
Get the 318, swap out the forged crank of the 273 and put the rest of the 273 stuff onto the 318 block. The crank will need to be balanced to the 60g heavier 318 pistons. They were all internally balanced. But life is simpler with the T-Flite Patty bushing...Just slip it into the larger crank bore and the old convertor will register true again
@Charrlie_S sold them at one time.
 
On the water pump issue - you can just swap water pumps without swapping the timing cover. Downside is that the lower radiator hose will partially cover the timing marks. However, if you put the 273 damper and the 273 timing mark that bolts to the bottom of the water pump, that will solve that problem. Of course, if you do all that, might as well just swap timing covers, too. Also, the 273 pulleys and alternator bracket will fit just fine on the 318 (if it's a non-air car; with A/C, I don't know).

I'm running my original 273 timing cover, bolt on timing mark, harmonic balancer, alternator brackets and pulleys, (new stock replacement) water pump, thermostat housing and upper radiator hose, and original but recored radiator on the 340 in my 65 Barracuda. I have also, in the past, run the later aluminum water pump and later (71 Duster) radiator. All that will fit, too, but won't leave room for a clutch fan if that's important to you.

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If you're keeping the stock '65 transmission, you will need the crank bushing to reduce the hole size to the small converter button. Depending on the year of the 318, you may have to modify the engine mount brackets. 318's with all four bracket ears on both sides shouldn't be a problem, but, some only have 3 ears on a side, and they're usually a different 3 ears than the 273. I'd convert the front end of the engine to the '65 parts just to keep from having to modify radiator and fan stuff. I'd put a new timing chain set in there while I was at it. Most 318 balancers are the same size as the 273, so, either swap it to the 273 balancer or use the 318 one if they match up sizewise. The 318 balancer from '72 and later had an even bolt pattern for the pulley. The earlier ones have one offset bolt hole (like the 273). You can slot the hole either way depending on which balancer you use. As for the timing mark, just cut the 273 TDC slot to the 318 balancer and highlight it with paint, if you decide to use it. There again, depending on the year of the 318, starting in the mid 70's the heads started to have smog ports drilled into them below the exhaust port. You'll need to plug them to use the 273 manifolds. The intake would depend on which choices you have with the 318 you get. The '65 intake won't fit on a 318. If you want the stock look, get an intake off a '66 or '67 model. That way you can use your stock carb, choke, and kickdown linkage without having to modify anything. If you get a 2bbl 318, get it with all the intake parts including the carb, choke, and air cleaner. You should be able to tranfer kickdown linkage from your 273 to the 318. If you go 4bbl. all that would have to be changed (check for hood clearance before getting an aftermarket intake). Another area that might need to swapped over is the oil pan, dipstick and tube, and oil pickup depending on year and what the 318 was in. If it were me, I'd also put a new set of brass freeze plugs in it, if they don't already have them. I'm sure I'm probably forgetting something, but, that's all I can think of now.
 
My 318 oil pan in a '65 Valiant hits the steering link when steering wheel turned too far, whereas the factory '65 273 oil pan has a dimple there to avoid any rubbing.
 
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