273

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66Glassback

66Glassback

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I recently removed my 273 Commando engine out of my 1966 Barracuda. I wanted to have it checked out and rebuilt. It was getting a small amount of oil in the coolant but no coolant in the oil. Other than that it ran great. The machine shop I sent it to found a small crack in the block. I have found someone that has a 273 that I could purchase and use the block as a doner. I was wondering, seeing where I am at, should I just find a 318 or a 360 to rebuild and will one of those motors be ok to hook up the A833 4 speed transmission to?
 
66Glassback said:
I recently removed my 273 Commando engine out of my 1966 Barracuda. I wanted to have it checked out and rebuilt. It was getting a small amount of oil in the coolant but no coolant in the oil. Other than that it ran great. The machine shop I sent it to found a small crack in the block. I have found someone that has a 273 that I could purchase and use the block as a doner. I was wondering, seeing where I am at, should I just find a 318 or a 360 to rebuild and will one of those motors be ok to hook up the A833 4 speed transmission to?
Click to expand...
You could use something bigger. I was thinking about this possibility with my 273. The 360 is externally balanced and I'm not sure what Flywheel you would need. Probably a larger diameter 360 flywheel and then a different bellhousing and some different linkage. That could be done but not a plug and play deal. What ever engine you will get you will need a pilot bushing in the end of the crank. There's probably other things you will have to change.
 
The Baby Commando is a fine motorvator for that Lightweight A.
Any other SBM will be a fine replacement. All can be made to work with your A833.
I have a Commando trans behind my HO360, with a 8.75 at the back, and they are all doing very well.

The only cons I see with a bigger engine in the early Barracuda, for street-duty, are;
1) the lack of rear wheelwell room to accept enough tire for to make a bigger engine worth it.
2) money
You should be able to fix that 273 and slam it back together fairly cheap. But if considering simultaneously a rebore, well then the money is, IMO, better spent on doing the same, on a bigger engine, cuz it's gonna cost the same, maybe even less.
An early hi-compression 318, will get you the same power, but as a 2bbl. Whereas the Smog-era 318, with your 4bbl on it will be torquierr but similar power to your 273.
Any 2-bbl-318, is gonna tax the small tire tires fitted at the back
And any bigger engine is pretty much overkill to the tires.

Performance makes heat and pretty soon the cooling system starts to complain.
As power goes up, your exhaust manifolds are gonna be the choke.
Pretty soon, one thing has led to another and the darn project has become a money pit.

What would I do?
Well,
I got this 340 block in the corner, and
a stack of heads including a nice set of closed-chamber 273 heads, and
a 360 2bbl cam, and
a few years ago I found an Offy Dualport which still has not found a home, and
recently, in shed #3, I found a box of TQs that I hadn't seen in 22 years, and
I know I have a set of 340 Exhaust manifolds hiding somewhere, plus
I got one A833 overdrive left in the basement, and somewhere,
is every rearend from 2.76s to 3.55s , all with posi's, yes guys, I said posi's..
But, I guess I'll need a bigger clutch, wohoo, got that too!
Surely;
I could put some thing together.
Where do you want it delivered? lol. .

Oh BTW
I could bring you a 273 core block; I mean it's on the way an'all....
 
When building a small block mopar to any level people would be generally better off starting with a 360 but saying that it's up to you, your desire/want/value etc..
 
Except for pistons, all your 273 parts will fit into a 318 block. A 360 would need much more to make it work. If you go that route, get a complete 360 short block if you plan to keep the 273 heads and stock exhaust manifolds. Or, get a 360 long block if you're willing to play with the exhaust system. You'd also have to modify engine mount brackets, find an oil pan that will work and not rub, flywheel rebalance or conversion to a later car flywheel, bell housing, clutch, etc. A lot will depend on what sort of performance you want, and what your budget is.
 
The 273 will cost you more to build, but your car looks pretty original and nice. If you want to keep it pretty much stock, get that 273 block and fix it. If you want to get a 318 block, all of your existing rotating assembly except the pistons will work right back into a 318 block, and you could use off the shelf pistons such as KB167's. Get it balanced with your existing flywheel and it all bolts right back in. I just built a 273 for my 65 Barracuda. I bought custom pistons from Race Tek and they were $700 per set.....since I bought 3 sets! I got 2 sets for me and another set for another FABO member. I built the one for the 65 just to say I'd done one and have to do 1 more because it's the numbers matching engine for our 69 Dart GT convertible. If I were you I would avoid a 360 because it will force you to buy a special 130 tooth flywheel, a 10.5" bell housing and special made linkage to make your clutch work. Decisions, decisions! :BangHead: Good luck with it.

:thumbsup:
 
Really the only thing that costs more to rebuild thr 273 are the pistons. You will have to go to Kanter or EGGE for them. Everything else including the machining is standard 273/318/340 stuff.
 
There is NOTHING at all wrong with the 273. it is a FINE motor. You would probably be very happy if you just rebuilt a 273. It will provide you with plenty of power for cruising around while giving you decent mileage. If, on the other hand, you are thinking about swapping the motor out, I would go with a 360 for several reasons.
1. The 360 has 87 cubic inches more than the 273. Even with a very mild build, a 360 could easily have 50-60 more HP and torque foot pounds than the 273.
2. If you spend a bunch of money rebuilding a 273 and change your mind for a bigger engine in a few years, you will be luck to sell your 273 for half of what you have in it.
 
If cost is a factor, building a 318 would be the cheapest. Next cheapest would be a 273, and the most expensive would be the 360 considering the extra parts and changes needed.
 
Main reason to go larger is idle-5000 rpm especially under 3000 rpm is where we live on the street and a 360 is generally gonna make more power there even for a super mild stockish build, plus rear gears we tend to run 2.76-3.55 are gonna be more favorable to a 360. A 318 is generally gonna like a half ratio more and a 273 a full ratio more for similar performance.
 
If you have Commando pistons already and they match up bore wise to 273 block you have access to, it's a no brainer. Rering, rebearing and cam upgrade if you so choose. I wanted to add more hp and looked at building a 318. From my memory 318 pistons to achieve decent compression werent cheap.
 
4spdragtop said:
If you have Commando pistons already and they match up bore wise to 273 block you have access to, it's a no brainer. Rering, rebearing and cam upgrade if you so choose. I wanted to add more hp and looked at building a 318. From my memory 318 pistons to achieve decent compression werent cheap.
Click to expand...
Best advice right there!

As long as your current 273 pistons fit the new block, it’s just a quick home with new rings and then it’s swap parts over. Even bearings around the crank and rods. Then a gasket kit.

If the pistons don’t fit….. then we are off to the races on what to do.
 
AJ/FormS said:
The only cons I see with a bigger engine in the early Barracuda, for street-duty, are;
1) the lack of rear wheelwell room to accept enough tire for to make a bigger engine worth it.
Click to expand...
That’s a ridiculous reason
AJ/FormS said:
2) money
Click to expand...
Another ridiculous reason.
All SBM engines cost the same except for pistons and an usual item that I can’t think off.
AJ/FormS said:
You should be able to fix that 273 and slam it back together fairly cheap.
Click to expand...
Block is cracked. Assuming you know more than the machinist that inspected the block with his own eyes vs your crystal ball is a lot of balls to state since that is saying your smarter better and wiser than the machinist that has seen the block while you haven’t.

Is it possible? I guess it could be that your luckier than a blind squirrel getting a nut in the middle of the Sahara desert.

AJ/FormS said:
But if considering simultaneously a rebore, well then the money is, IMO, better spent on doing the same, on a bigger engine, cuz it's gonna cost the same, maybe even less.
Click to expand...
Only in pistons
AJ/FormS said:
An early hi-compression 318,
Click to expand...
If one exists that’s in good reliable shape after all these years…


AJ/FormS said:
Any 2-bbl-318, is gonna tax the small tire tires fitted at the back
And any bigger engine is pretty much overkill to the tires.
Click to expand...
That’s if you have no control over your right foot.
AJ/FormS said:
Performance makes heat and pretty soon the cooling system starts to complain.
Click to expand...
Same radiator is used between the engines
AJ/FormS said:
As power goes up, your exhaust manifolds are gonna be the choke.
Click to expand...
They’re a choke from the factory. An even worse choke is the 318 manifolds. Port size is the same.
AJ/FormS said:
Pretty soon, one thing has led to another and the darn project has become a money pit.
Click to expand...
If it has fits and wheels, it’s always expensive. Next…..
AJ/FormS said:
What would I do?
Click to expand...
Oh dear heavens…. Here we go now…
AJ/FormS said:
Well,
I got this 340 block in the corner, and
a stack of heads including a nice set of closed-chamber 273 heads, and
a 360 2bbl cam, and
a few years ago I found an Offy Dualport which still has not found a home, and
recently, in shed #3, I found a box of TQs that I hadn't seen in 22 years, and
I know I have a set of 340 Exhaust manifolds hiding somewhere, plus
I got one A833 overdrive left in the basement, and somewhere,
is every rearend from 2.76s to 3.55s , all with posi's, yes guys, I said posi's..
But, I guess I'll need a bigger clutch, wohoo, got that too!
Surely;
I could put some thing together.
Where do you want it delivered? lol. .
Click to expand...
Free of charge? Awesome! Like the idea. I wonder what the OP has in spare parts?
AJ/FormS said:
Oh BTW
I could bring you a 273 core block; I mean it's on the way an'all....
Click to expand...
Now there! Is a possible solution!

Could have saved time blabbering away with nonsense and made that offer to start with.
 
rumblefish360 said:
Is how I feel when I read your long winded replies leading no where.

Is how I feel about you. Though you are a good guy. Love ya man!
Enjoy the day.
Click to expand...
It's getting to the point that I hesitate to post my opinion ,for fear that, even tho opinions have been asked for, you are gonna pick mine to pieces . This is getting stinking old.
I mean you can have an opinion too, but that does not mean that you have to automatically trample on mine. I mean, just post your opinion and move along.
 
66Glassback said:
I recently removed my 273 Commando engine out of my 1966 Barracuda. I wanted to have it checked out and rebuilt. It was getting a small amount of oil in the coolant but no coolant in the oil. Other than that it ran great. The machine shop I sent it to found a small crack in the block. I have found someone that has a 273 that I could purchase and use the block as a doner. I was wondering, seeing where I am at, should I just find a 318 or a 360 to rebuild and will one of those motors be ok to hook up the A833 4 speed transmission to?
Click to expand...
I think there is a guy in new york that has a 67 commando 273 posted in the mechanical parts section on this site
 
AJ/FormS said:
It's getting to the point that I hesitate to post my opinion ,for fear that, even tho opinions have been asked for, you are gonna pick mine to pieces . This is getting stinking old.
I mean you can have an opinion too, but that does not mean that you have to automatically trample on mine. I mean, just post your opinion and move along.
Click to expand...
Just keep doing what your doing, I don't always agree with you on some things you say but that's ok, some people give me grief to on how I think, it's all good, you do have a lot of valuable info to pass on, don't let others stop ya.
 
66Glassback said:
I recently removed my 273 Commando engine out of my 1966 Barracuda. I wanted to have it checked out and rebuilt. It was getting a small amount of oil in the coolant but no coolant in the oil. Other than that it ran great. The machine shop I sent it to found a small crack in the block. I have found someone that has a 273 that I could purchase and use the block as a doner. I was wondering, seeing where I am at, should I just find a 318 or a 360 to rebuild and will one of those motors be ok to hook up the A833 4 speed transmission to?
Click to expand...
64mopar64 the man is in clifton park new york. I bought a set of mags from him and he was totally on the up and up.
 
AJ/FormS said:
It's getting to the point that I hesitate to post my opinion ,for fear that, even tho opinions have been asked for, you are gonna pick mine to pieces . This is getting stinking old.
I mean you can have an opinion too, but that does not mean that you have to automatically trample on mine. I mean, just post your opinion and move along.
Click to expand...
Love ya AJ. Try answeing the question directly then instead of spreading your opinion on other topics like, you’ll just spin tires as if the OP has no control over their right foot. Your tire tech is poor and the drivability of these cars is fine within there limits, not what you enjoy pushing them beyond and then call it shity.
273 said:
Just keep doing what your doing, I don't always agree with you on some things you say but that's ok, some people give me grief to on how I think, it's all good, you do have a lot of valuable info to pass on, don't let others stop ya.
Click to expand...
He is right AJ. We banter and move on. Next
 
Hey everyone, just wanted to update you on the block. In the picture is where the oil filter housing mount goes. Someone drilled out the hole and epoxied a sleeve in it. That is where the oil in the coolant is coming from. I found a good 273 block that I am going to pick up tomorrow. Thanks for everyone's response (even all the quarreling... I kind of found it funny.) I will update with some more pictures later.

273 block.jpg
 
I’m looking at that picture with only this screaming through my head….


WTF?!?!?!
 
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