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

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GHOST RUSTERS

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Hello everyone! Thank you to all the members who took the time to read and contribute to my previous thread regarding my dads 273 and the cam options.

I just had a 2 hour conversation with my dad and it turns out that there was a critical missing piece to the story that had NEVER been revealed to me.

The 273 in my dads barracuda (the engine that I have now and was trying to refresh) is NOT the cars original engine and therefore is NOT the engine that he worked on and learned to wrench with. Having said that, he made it clear to me that he had no sentimental value to THAT engine and gave me his blessing to looking into swapping the engine for a healthier and more financially comfortable option. I’m thinking 318???

So, moving forward. Being that the crank and the cam issues alone on the 273 are presenting issues, cost for machine work, difficulty finding head gaskets, camshaft solutions without other costly adjustments and so on, I am here to clean the slate and look for opinions, experience and education to putting in a 318 instead and what transmission?

Again. My current setup is the following: 1965 Plymouth barracuda V8 with automatic A904 (cable shift)

The costs and difficulties, for me at least, with the 273 has put me in the position of, is it true in saying that a 318 is a healthier choice as far as parts availability now and in the future, cost effectiveness for the build and potential for a little more build options being able to look into the 4 barrel vs the limited 2 barrel on the 273.

Also, how would this affect the existing 904? Which btw has a “broken reverse band” and will need repair/ work. Would it make more sense to find and install a 318/727 combo?

Again, I am lost here and only looking to build a safe, road worthy car that the family and I can enjoy for some car shows and weekend driving. NO hot rodding. But if possible and not too much to ask, an exhaust tone worth a little growl would be nice, the kids love it!

Please see my previous post “273/ 2 barrel camshaft options” if you would like a refresher or to see my original introduction. Not looking to waste anyone’s time so I apologize ahead of time for babbling or not knowing what I don’t know. Thanks!

IMG_8653.png
 
You'll be much better off finding a decent 5.2 or 5.9 Magnum core and building that.
 
You'll be much better off finding a decent 5.2 or 5.9 Magnum core and building that.
Would you be able to elaborate how do you mean better off? As in readily available to find a good one worth building? Or overall period build potential for my needs? I don’t want to swap any parts off of the 273, just going to pretend it’s not here, so what’s involved in building the 5.2 or 5.9 for a basic cruiser? Trans options? Exhaust issues? Thank you for chiming in!
 
Would you be able to elaborate how do you mean better off? As in readily available to find a good one worth building? Or overall period build potential for my needs? I don’t want to swap any parts off of the 273, just going to pretend it’s not here, so what’s involved in building the 5.2 or 5.9 for a basic cruiser? Trans options? Exhaust issues? Thank you for chiming in!
Easier to find a good core. The LA stuff is getting really old.
 
Thanks I appreciate that! I’ll point my research in that direction and see about finding one. What can I expect to pay for one? Any trans recommendations?
That's totally location dependent. If you have an LKQ in your area, that would be a place to start. Go with a mid 70s 904 and you'll have the part throttle kickdown. Any type of automatic overdrive will require big floorpan modifications.
 
That's totally location dependent. If you have an LKQ in your area, that would be a place to start. Go with a mid 70s 904 and you'll have the part throttle kickdown. Any type of automatic overdrive will require big floorpan modifications.
Would my 65 904 transmission be a worth while candidate?
 
Just keep in mind the second you step away from the 273/318 build the conversion cost kicks in.

Just about everything on a 273 works on the 318, they are essentially the same engine.


Alan
 
looking into swapping the engine for a healthier and more financially comfortable option. I’m thinking 318???

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.

camshaft solutions without other costly adjustments

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.

The costs and difficulties, for me at least, with the 273 has put me in the position of, is it true in saying that a 318 is a healthier choice as far as parts availability now and in the future, cost effectiveness for the build and potential for a little more build options being able to look into the 4 barrel vs the limited 2 barrel on the 273.

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.

Also, how would this affect the existing 904? Which btw has a “broken reverse band” and will need repair/ work. Would it make more sense to find and install a 318/727 combo?

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.

Again, I am lost here and only looking to build a safe, road worthy car that the family and I can enjoy for some car shows and weekend driving. NO hot rodding. But if possible and not too much to ask, an exhaust tone worth a little growl would be nice, the kids love it!

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.

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!
 
okay, let's start with the transmission. it's early, it's cable operated, some parts are getting tough to come by and they can be a little finnicky. but, that transmission only really works with your shifter. so if you're in love with that set up, you're (basically) beholden to the early transmission. which is fine for the type of driving it sounds like you want to do.

but here in lies the rub: if you use anything besides a 67 and earlier 273 you're going to need the adapter ring for the torqe converter hub to crank register interface. no big deal, somebody here makes and sells that. or, you change your transmission and run an aftermarket shifter-- this is a bit better route in that you get a broader selection of parts availability, part time kickdown/passing gear, and there are more units out there floating around-- literally any 904 from 68 until the 80's can work.

to note, there exists products and procedures for adapting and/or making the later transmission work with the 65 shifter stuff.

as to the motor, i'd probably keep it LA 318 and forgo the 5.2 magnum (or 5.9) dance. as mentioned upthread, a big chonk of your 273 stuff will work with LA 318 where as with the later magnum motor you'll be putting out for a big number of things that are costly: heads, mainly. while it's clearly been done, sometimes just keeping it simple might be the best approach. you can pick up a reman long block for 2 grand or so, snap some bits & pieces on and be well on your way down the road.

exhaust with your build i'd just run stock manifolds, take it as true dual out to the back with some decent mufflers and call it done. if you're feeling flush, lay down the 1K or so for headers that actually fit.

the rear end, you can probably ride it till it pukes and then just throw an upgrade into it. there's reams of info here on the site regarding rear end swaps. it basically comes down to do you want to keep it small bolt pattern or go to big bolt pattern and how much you want to spend or fabricate. this kind of runs some what the same way the transmission does in that you need to pick a direction early on and then build toward that, otherwise you wind up spending the money twice.
 
Stock magnum 5.9 with chinese air gap intake is the most cost effective solution for a massive increase in torque.
 
Hello everyone! Thank you to all the members who took the time to read and contribute to my previous thread regarding my dads 273 and the cam options.

I just had a 2 hour conversation with my dad and it turns out that there was a critical missing piece to the story that had NEVER been revealed to me.

The 273 in my dads barracuda (the engine that I have now and was trying to refresh) is NOT the cars original engine and therefore is NOT the engine that he worked on and learned to wrench with. Having said that, he made it clear to me that he had no sentimental value to THAT engine and gave me his blessing to looking into swapping the engine for a healthier and more financially comfortable option. I’m thinking 318???

So, moving forward. Being that the crank and the cam issues alone on the 273 are presenting issues, cost for machine work, difficulty finding head gaskets, camshaft solutions without other costly adjustments and so on, I am here to clean the slate and look for opinions, experience and education to putting in a 318 instead and what transmission?

Again. My current setup is the following: 1965 Plymouth barracuda V8 with automatic A904 (cable shift)

The costs and difficulties, for me at least, with the 273 has put me in the position of, is it true in saying that a 318 is a healthier choice as far as parts availability now and in the future, cost effectiveness for the build and potential for a little more build options being able to look into the 4 barrel vs the limited 2 barrel on the 273.

Also, how would this affect the existing 904? Which btw has a “broken reverse band” and will need repair/ work. Would it make more sense to find and install a 318/727 combo?

Again, I am lost here and only looking to build a safe, road worthy car that the family and I can enjoy for some car shows and weekend driving. NO hot rodding. But if possible and not too much to ask, an exhaust tone worth a little growl would be nice, the kids love it!

Please see my previous post “273/ 2 barrel camshaft options” if you would like a refresher or to see my original introduction. Not looking to waste anyone’s time so I apologize ahead of time for babbling or not knowing what I don’t know. Thanks!

Sounds like you first need to decide what you want. What do you need to get your 273 done? The cam I offered to sell you is as close as we could get to a stock Commando 4 barrel cam. It would work for a 2 barrel or 4 barrel carb. A used 273 or 318 crank should not cost much. Done, nothing else to change, except possibly an adapter ring for a later crankshaft to use the "65" 904 torque converter. A 5.2 (318) Magnum would be a good choice except the heads are very prone to cracking. Going to a 318 LA has compression issues unless you get lucky and find an early engine. Going to a 4 barrel carb is more complicated than one would think, by the time you get the transmission kick down correct and get the right throttle cable bracket, after the cost of an intake and carb. You can use any 904 Transmission since you are changing the crankshaft, but then you will need a different driveshaft and shifter. Not worth using a 727 automatic, they don't fit well in an early Barracuda. Take the time to write it all down and compare all the work and costs, starting now.
 
Sounds like you first need to decide what you want. What do you need to get your 273 done? The cam I offered to sell you is as close as we could get to a stock Commando 4 barrel cam. It would work for a 2 barrel or 4 barrel carb. A used 273 or 318 crank should not cost much. Done, nothing else to change, except possibly an adapter ring for a later crankshaft to use the "65" 904 torque converter. A 5.2 (318) Magnum would be a good choice except the heads are very prone to cracking. Going to a 318 LA has compression issues unless you get lucky and find an early engine. Going to a 4 barrel carb is more complicated than one would think, by the time you get the transmission kick down correct and get the right throttle cable bracket, after the cost of an intake and carb. You can use any 904 Transmission since you are changing the crankshaft, but then you will need a different driveshaft and shifter. Not worth using a 727 automatic, they don't fit well in an early Barracuda. Take the time to write it all down and compare all the work and costs, starting now.
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 and reusing the existing piston rings, wrist pins and the like, no boring either, 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… this still leaves with either rodding the original radiator at unknown condition or $700 for a new one…

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 a 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.

With This new information regarding the 273 not being “my dads engine” I am open to any and all best solve-all solutions to get back on the road… that includes whatever engine l, shifter and or transmission changes as well, I am not dedicated or stuck on any particular path here, it’s a clean slate of a 65 barracuda… what can I do today that’ll Ill appreciate and be thankful that I did in 10 years? As rusty ratrod mentioned I did find a 5.2 magnum with a warranty for $1500…

IMG_8740.png
 
Take the path of least resistance, as in affordability and ease of assembling and installing without having to buy specialty make it fit parts. Your goal should be to get it on the road asap without frustration of a long build. A car of that age is going to have other work going forward, body work and paint, interior repair, brakes, tires and so on. It never ends. You don’t want to start a project and end up not seeing light at the end of the tunnel.
 
Take the path of least resistance, as in affordability and ease of assembling and installing without having to buy specialty make it fit parts. Your goal should be to get it on the road asap without frustration of a long build. A car of that age is going to have other work going forward, body work and paint, interior repair, brakes, tires and so on. It never ends. You don’t want to start a project and end up not seeing light at the end of the tunnel.
You read my mind and in so many attempts that’s EXACTLY what I have been trying to convey in my posts and transparency. Maybe I didn’t do it well enough. I am new to all of this in sharing and communicating. But thankful for the community and the folks here.

Staying on that topic of “path of least resistance” do you have any advice and or experience with the subject? 273 build vs LA 318 vs magnum? Along with trans, exhaust and read end concerns?

You said it best and that’s what I’m hopeful can be done. Thanks!
 
Doesn't the 65 904 have a factory cable shifter? If you want to retain that, you'll have to stay with the 65 trans.
 
That is not like an aftermarket cable shifter. If you get a good transmission guy, he can make that trans work good.
 
That is not like an aftermarket cable shifter. If you get a good transmission guy, he can make that trans work good.
If I may ask, if you’re familiar with my current situation, which option are you in favor of? Trying to revive the 273 that I have, looking into an LA 318 or a magnum 5.2 for this application? Or any other “path of least resistance” options I might be missing. Thanks!
 
The Magnum engines are better tech, are low cost and easy to obtain. The 360 is preferred because its bigger. The bores of either 318 or 360 Magnum most of the time are very healthy due to coming from a fuel injected engine- no flooding and washing down of cylinders like an LA engine with a stuck float in the carburetor. The Magnum heads have a nice efficient small comb chamber. Unlike an LA Head but stock Mag heads are limited to .550" lift stock. (Valve guides will need machined down for more lift. The Magnum engine is a Hyd Roller cam engine. Go with the stock cam and enjoy idle to say 5200 RPM performance or send the cam out for a regrind and make more power. Those HYD roller cams produce amazing power WITHOUT a ton of duration. Magnum heads will be cacked between the int and exh seat but they're all that way and apparently it poses zero problems for a stock or higher perf build. On FBMP a complete 360 will typically be $300- $600- at least in my area.
 
I say this with all the fellow car guy love I know how so don't take it personally. It sounds like you want someone to lead you by the hand through this. That ain't gonna happen. You are going to have to make up your own mind what you want and how to go about it. We're here to help with things if you get hung up on something, but we can't make your mind up for you. I know what I would do, but whether that meets your wants or needs is anybody's guess.
 
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The Magnum engines are better tech, are low cost and easy to obtain. The 360 is preferred because its bigger. The bores of either 318 or 360 Magnum most of the time are very healthy due to coming from a fuel injected engine- no flooding and washing down of cylinders like an LA engine with a stuck float in the carburetor. The Magnum heads have a nice efficient small comb chamber. Unlike an LA Head but stock Mag heads are limited to .550" lift stock. (Valve guides will need machined down for more lift. The Magnum engine is a Hyd Roller cam engine. Go with the stock cam and enjoy idle to say 5200 RPM performance or send the cam out for a regrind and make more power. Those HYD roller cams produce amazing power WITHOUT a ton of duration. Magnum heads will be cacked between the int and exh seat but they're all that way and apparently it poses zero problems for a stock or higher perf build. On FBMP a complete 360 will typically be $300- $600- at least in my area.
I would prefer to keep everything simple and stock if possible. No need or performance mods or HP expenses. It’ll be a cruiser as mentioned. I’m more interested in simplicity, safety and a healthy invest for future needs if a rebuild should ever arise again in X amount of miles/ use.

Having said that. Do you have experience or preference between a 5.2 vs 5.9?

Am I understanding correctly?

Find a decent block. (Any particular years to look for?)

Convert everything from efi to carbureted as needed. Manifold and carb. (Are there any major electrical or other concerns or issues in going from efi to carb?)

Will I be using the exhausts manifolds off of my 273 or use the ones a magnum comes with?

And the approach the ideal transmission and rear end issues?

Also a thought, will a magnum swap need any work related to more weight than the original 273? Suspension, brakes, k-member concerns?

I apologize as I don’t know what I don’t know. Again, goal here is “path of least resistance” (and if you saw my earlier posts, I did come across a 5.2 complete with a 5 year warranty, if it’s not a scam??? No idea) otherwise I’m hunting around on FBMP and classifieds looking for a doable magnum.

Oh! Also, would a magnum allow me the opportunity to eventually look into power brakes and power steering???? Thanks again!
 
I say this with all the fellow car buy love I know how so don't take it personally. It sounds like you want someone to lead you by the hand through this. That ain't gonna happen. You are going to have to make up your own mind what you want and how to go about it. We're here to help with things if you get hung up on something, but we can't make your mind up for you. I know what I would do, but whether that meets your wants or needs is anybody's guess.
I can appreciate that and respect where you’re coming from. Perhaps I reached to deeply and it came off as a “help me!” And I’m not looking to waste anyone’s time here in that regard. I guess I came to a crossroad on 273 vs 318 magnum and was looking for experience and or guidance in making an educated decision for the needs that I feel I have mentioned. Regardless, no offense taken. I appreciate the time and efforts on everyone here. I’ll tone it way down on my part in crying and find a way to continue moving forward. Thank you for the feedback.
 
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