273 swap to 318/ build, cost, potential, daily driver

excellent. but don't delude yourself, sourcing and building an engine is almost always more expensive that what you budget for. are certain aspects of a 318 build cheaper and easier than a 273? yes, absolutely. but a lot of the hard costs remain the same; machine shop work costs dough no matter the size of the engine.



although we're moving on from the 273 i'd like to make a point that there are *plenty* of affordable camshaft solutions for these motors. you don't *have* to run a solid lifter, you can reuse your factory adjustable rockers and aside from being easy to over cam, they follow the same rules as any other engine in the family.



yes, the 318 enjoys a broader range of parts availability and therefore has some better options price wise for critical components. among that would be a 4 barrel intakes.



your 904 being pre 1968 wil have a smaller center hub on the torque converter, this matches the crank register of pre 1968 engines. so if you run any motor that is 68 and up, it will have the larger center register on the crank and you will need an adapter ring to center the small hub of the early transmission. also, aftermarket torque converters for the early transmissions are prohibitively expensive.

a 904 will be more than sufficient for your needs.



i'll start with the usual, what's your budget? how much work can you do yourself? the easy button exists, and it's an easy press, but that means spending more money. are you okay with hustling market place, classifieds, craig's list and offer up for parts? or are you more about that "new-new" life?

anyway, here's how i'd roll: scoop up a reman long block with a warranty. swap the cam for something decent (under .450 lift, less than 260 duration), top it up with a performer and a small 600~650 carb then reuse a whole boat load of your 273 stuff-- timing cover, engine tins, distributor and run it thru the stock maifolds. then sell off all the 273 stuff you don't need.

obviously the above is open to interpretation and subject to change, say you scored a sweet pull out motor and trans? then apply most of the same stuff but you don't have a warranty on the motor. so, there's pros and cons to each method of attack.

excellent. but don't delude yourself, sourcing and building an engine is almost always more expensive that what you budget for. are certain aspects of a 318 build cheaper and easier than a 273? yes, absolutely. but a lot of the hard costs remain the same; machine shop work costs dough no matter the size of the engine.



although we're moving on from the 273 i'd like to make a point that there are *plenty* of affordable camshaft solutions for these motors. you don't *have* to run a solid lifter, you can reuse your factory adjustable rockers and aside from being easy to over cam, they follow the same rules as any other engine in the family.



yes, the 318 enjoys a broader range of parts availability and therefore has some better options price wise for critical components. among that would be a 4 barrel intakes.



your 904 being pre 1968 wil have a smaller center hub on the torque converter, this matches the crank register of pre 1968 engines. so if you run any motor that is 68 and up, it will have the larger center register on the crank and you will need an adapter ring to center the small hub of the early transmission. also, aftermarket torque converters for the early transmissions are prohibitively expensive.

a 904 will be more than sufficient for your needs.



i'll start with the usual, what's your budget? how much work can you do yourself? the easy button exists, and it's an easy press, but that means spending more money. are you okay with hustling market place, classifieds, craig's list and offer up for parts? or are you more about that "new-new" life?

anyway, here's how i'd roll: scoop up a reman long block with a warranty. swap the cam for something decent (under .450 lift, less than 260 duration), top it up with a performer and a small 600~650 carb then reuse a whole boat load of your 273 stuff-- timing cover, engine tins, distributor and run it thru the stock maifolds. then sell off all the 273 stuff you don't need.

obviously the above is open to interpretation and subject to change, say you scored a sweet pull out motor and trans? then apply most of the same stuff but you don't have a warranty on the motor. so, there's pros and cons to each method of attack.
Wow! Thank you so much for the time and effort in such a detailed response! This is great information that I can look into. I honestly don’t know what to do here… I’m being told that the crank and the cam are toast in my 273, and with the scarcity of affordable and available parts which may get harder as time goes on, I was advised against using the engine, then discovering it’s no longer as sentimentally valuable as previously thought, I came here exploring the next step.

You make a solid point, and to be fair, budget IS driving this project, BUT there are finances available to do this. But which option is the smarter of the two between the 273 that I have, or finding and using a 5.2/5.9 magnum?

With the 273, The machine shop put me at $950-$1100 for tanking, magging and cleaning the heads and block, also includes valve job (give or take additional work or parts needed), installing freeze plugs, installing cam bearings and cam (when and if one was found without other major costly modifications) that’s a rough estimate and description… WITHOUT machine work such as boring… they suggested a new cam and crank… (both rusted and pitted) then a rough estimate of $350-450 in additional parts… rod and main bearings, oil pump, water pump and so on… they did mention difficulties in finding head gaskets (.040) and a few other concerns…

So here I’m, for exactly the type of education that you provided. I understand and respect that ANYTHING can be done with the “money-time-energy” formula and that quality isn’t cheap…

I have my dad’s 1965 barracuda, that goes all the way back to his mom and dad. The 273 it has is not original nor crucial to him or me. I’d like to make it safe and road worthy to surprise my dad one day and be able to take my girls out for ice cream with it and enjoy a few car show cruises.

So, with my 904 transmission and EVERYTHING out of the car… i don’t know which way to go in making a smart, financially comfortable decision…

I am not a professional engine builder, but I am mechanically inclined (been an me mechanic in some way or another since I was a Teenager) I have assembled and disassembled engines and I’m not afraid to ask for help or to learn. (For what it’s worth, NO ONE within my area 4+hours in either direction, offers to build or assemble an engine)

BTW totally ok with scavenging marketplace and classifieds and networking, I’m certainly not a “new-new” type of fella… I’m a what’s available and DIYer with a positive attitude…

So, please, if you have the time and patience, educate me here with my options and how or why I should take on the 273 or the 318 or magnum or any other ideal solutions and how to solve the transmission and or exhaust and rear end concerns, if any, or anything else that I might be missing. I’ll try and shut up now. But Thank you again for your time and patience!