1966 273 Commando - Thoughts

-

BigB6958

Active Member
Joined
Aug 7, 2024
Messages
36
Reaction score
25
Location
Calgary Canada
As I am still making decisions about what to power my 67 Dart GT conv I am constantly looking at what is out there for sale. Came upon this and wondered if those with good experience would be able to offer opinions as to whether it might be a decent option. I have read good things about these engines. I know they may not have the torque of a 360 and I can get 350hp from this build fairly easily I think. Add a set of headers and a better distributor, couple of other things, but mostly leave as-is. I am not looking for a tire burning race car....just something to cruise around with that looks AND sounds nice, and have some get up and go when I want it to. With a change of gearing in the back end I think this might be an option. Plus a Commando, although not numbers matching, would be more period correct I think. The guy wants $6500 CAD for this setup...love to get some feedback, and I look forward to thoughts on this.

Thanks'
BigB

"1966 273ci Commando Complete Rebuilt bored 30 over new Dome Pistons 10:1 compression Falcon Ultimate Cam Shaft Kit Cam Street & Strip, 287 dur 480 lift Double Roller Timing Chain, Hi Volume Oil Pump, Steel Crank , Heads 1.88 Intake and 1.60 exhaust and Port Matched to Edelbrock LD4B intake manifold, Crank and Block Shot Peened, Original dual points distributor, Original exhaust manifolds, 625 CFM Competition Series Carter carburetor, have original 273ci Commando Intake manifold"

1732493825301.png
 
Last edited:
I don't know what the exchange rate is bit 6500 sounds like a stretch. Although, my 273 cost me about $3500 to build.
 
Paid $3500 USD for this

 
As I am still making decisions about what to power my 67 Dart GT conv I am constantly looking at what is out there for sale. Came upon this and wondered if those with good experience would be able to offer opinions as to whether it might be a decent option. I have read good things about these engines. I know they may not have the torque of a 360 and I can get 350hp from this build fairly easily I think. Add a set of headers and a better distributor, couple of other things, but mostly leave as-is. I am not looking for a tire burning race car....just something to cruise around with that looks AND sounds nice, and have some get up and go when I want it to. With a change of gearing in the back end I think this might be an option. Plus a Commando, although not numbers matching, would be more period correct I think. The guy wants $6500 CAD for this setup...love to get some feedback, and I look forward to thoughts on this.

Thanks'
BigB

"1966 273ci Commando Complete Rebuilt bored 30 over new Dome Pistons 10:1 compression Falcon Ultimate Cam Shaft Kit Cam Street & Strip, 287 dur 480 lift Double Roller Timing Chain, Hi Volume Oil Pump, Steel Crank , Heads 1.88 Intake and 1.60 exhaust and Port Matched to Edelbrock LD4B intake manifold, Crank and Block Shot Peened, Original dual points distributor, Original exhaust manifolds, 625 CFM Competition Series Carter carburetor, have original 273ci Commando Intake manifold"

View attachment 1716331680
350 horse out of a 273 is possible, but going to be a bit of a stretch at 1.28+ c.i./h.p.- and will take more than a distributor and headers. And when a motor that size is pushed to those power levels, it's going to get finickier and finickier...
They are fine, fun motors for a street cruiser, with enough spunk to get the job done when called upon; just don't get carried away with horsepower expectations. Even the special order 1966 "D/Stock" factory race Darts were "only" putting out about 275 horses as delivered...
IMO, a mildly upgraded Commando/Charger motor (which is what that engine appears to be, although the cam may be a hair large for your average cruiser 273) will meet all your expectations on the street- just don't get too hung up on HP numbers.
As far as sounding nice, the Commando/Charger 273 engines had one of the best sounding exhausts ever engineered- and it was a single!
 
350 horse out of a 273 is possible, but going to be a bit of a stretch at 1.28+ c.i./h.p.- and will take more than a distributor and headers. And when a motor that size is pushed to those power levels, it's going to get finickier and finickier...
They are fine, fun motors for a street cruiser, with enough spunk to get the job done when called upon; just don't get carried away with horsepower expectations. Even the special order 1966 "D/Stock" factory race Darts were "only" putting out about 275 horses as delivered...
IMO, a mildly upgraded Commando/Charger motor (which is what that engine appears to be, although the cam may be a hair large for your average cruiser 273) will meet all your expectations on the street- just don't get too hung up on HP numbers.
As far as sounding nice, the Commando/Charger 273 engines had one of the best sounding exhausts ever engineered- and it was a single!
Excellent feedback, and I am def not hung up on HP. I was just tossing numbers. He suggested this was about 305-315 as it sits and I thought a set of headers and better dist might get another 25 out. But even if just 325 or 330 thats plenty for a small car like this and def good for cruising. The sound is what i am looking for and the cam should give it a good roll.

Just going through my options and ideas. Car is hopefully on the road for next season, although that might be a stretch, so motors are on the list but not top of the list. If someone said this was a "must have" i would do it. But there are plenty of 360's out there as well....and you never know. A 440 could make its way into the mix too.
 
350 horse out of a 273 is possible, but going to be a bit of a stretch at 1.28+ c.i./h.p.- and will take more than a distributor and headers. And when a motor that size is pushed to those power levels, it's going to get finickier and finickier...
They are fine, fun motors for a street cruiser, with enough spunk to get the job done when called upon; just don't get carried away with horsepower expectations. Even the special order 1966 "D/Stock" factory race Darts were "only" putting out about 275 horses as delivered...
IMO, a mildly upgraded Commando/Charger motor (which is what that engine appears to be, although the cam may be a hair large for your average cruiser 273) will meet all your expectations on the street- just don't get too hung up on HP numbers.
As far as sounding nice, the Commando/Charger 273 engines had one of the best sounding exhausts ever engineered- and it was a single!
Yep.
 
you cant beat Cubic Inches.

You can add all the Commando/ Charger valve covers, intake carb etc and unless someone looks really hard will never know its a 360 based engine
 
you cant beat Cubic Inches.

You can add all the Commando/ Charger valve covers, intake carb etc and unless someone looks really hard will never know its a 360 based engine
Well, OP isn't trying to "beat" anybody... just have a rumbly cruiser.
And I know of a couple local 2.2s that regularly take down 5.7s- of both the LS and Hemi variety. Without nitrous.
But yeah, a 360 is the easy way out- I have a full dress "Sham-mando" in my '66 wagon. Not to pull ETs, but to pull a camper.
 
If yur contemplating hiway miles to cruize-ins with a 273, a stall to match a 287/cam, and say at least 3.91s, then yur gonna need an overdrive. That's like 3000>4000, plus cutting up the floor.
For less money and better IMO performance, you can drop in any lazy-azz 360 with a 4-barrel and just leave whatever is already in there, in there. The downside is you loose the idle-lope of big-cam.
But the good news is, there are cams available specifically to cover that characteristic.
Plus, for a few bucks more, that 360 can be sporting a 10.7 Scr, and smoking 2.94 gears to at least 60 mph, which I know you'll never want to do, right? lol. Until the first time, lol, then you'll do it again and again and .............
Just paint it red and put a 318 top end on it, and it will still smoke the tires in your 67.
 
that combo *might* make 350 with a 750 on top and spun up to 6K, but it's more likely to be in the 325 range even with headers.

i *think* that cam is on a 109 so it should sound pretty good. hope you don't have power brakes.
 
Ted Spehar propelled the little 275 HP superstocker to 106 MPH at 12.91. If you need more than that in a convertible you might need a bigger engine. $4700 is a fair price unless you are a machinist and can do the work yourself. Is it a chunk of change? Yes but it's done and looks great. Best of luck with the project!
 
On a minor note, you would need to drill one of the engine mount holes in the block.


Alan
 
That's a lot more than I'd pay for a 273.
I'd look for a 5.9 Magnum for that money (with a roller cam) or a 5.2 for less than that.
I understand that a cruiser is desired.... but I'd still rather have more motor for less money.
 
That's a lot more than I'd pay for a 273.
I'd look for a 5.9 Magnum for that money (with a roller cam) or a 5.2 for less than that.
I understand that a cruiser is desired.... but I'd still rather have more motor for less money.
I tend to agree but was just looking for advice on this one because it seems to be built well and it is a Commando so it is more period correct for the 67. That being said, since I am going restomod for a lot of the car, period correct might be something I need to worry less about.
 
I tend to agree but was just looking for advice on this one because it seems to be built well and it is a Commando so it is more period correct for the 67. That being said, since I am going restomod for a lot of the car, period correct might be something I need to worry less about.
I wouldn't worry about it. That 273 is a virtually indestructible forged crank small block. How often do you see a factory engine that makes more horsepower than cubic inch size? Going purely by the description of the seller that 1966 273 is better than new mechanically and then you add a port matched LD4B to the 66 heads it should breathe well. Find a stock 5.2 or 5.9 engine that makes as much horsepower as that already complete 273. My wife and I have 9 cars with commando 273's. I wouldn't pull one of them for any other LA small block for what your end goals are!
 
Missing a lot of the "special" parts that make it a commando.
Agree, there is nothing "Commando" about this, just a standard 273 built up, may have started as a "Commando" but like said, without the intake and valve covers it might as well be a standard 273.


Alan
 
As I am still making decisions about what to power my 67 Dart GT conv I am constantly looking at what is out there for sale. Came upon this and wondered if those with good experience would be able to offer opinions as to whether it might be a decent option. I have read good things about these engines. I know they may not have the torque of a 360 and I can get 350hp from this build fairly easily I think. Add a set of headers and a better distributor, couple of other things, but mostly leave as-is. I am not looking for a tire burning race car....just something to cruise around with that looks AND sounds nice, and have some get up and go when I want it to. With a change of gearing in the back end I think this might be an option. Plus a Commando, although not numbers matching, would be more period correct I think. The guy wants $6500 CAD for this setup...love to get some feedback, and I look forward to thoughts on this.

Thanks'
BigB

"1966 273ci Commando Complete Rebuilt bored 30 over new Dome Pistons 10:1 compression Falcon Ultimate Cam Shaft Kit Cam Street & Strip, 287 dur 480 lift Double Roller Timing Chain, Hi Volume Oil Pump, Steel Crank , Heads 1.88 Intake and 1.60 exhaust and Port Matched to Edelbrock LD4B intake manifold, Crank and Block Shot Peened, Original dual points distributor, Original exhaust manifolds, 625 CFM Competition Series Carter carburetor, have original 273ci Commando Intake manifold"

All the really cool and expensive Charger, since we are talking Dart, stuff is missing. Pretty hard to get a better distributor than a cast iron Prestolite distributor with the right curve and ball bearing vacuum advance plate. I have run a 284 duration cam in a 273, and found a smaller cam is much better all around, unless you want to make a drag racer out of it. Is that a solid lifter cam? 1.88 intake valves get real close to the cylinder wall, I hope he knew what he was doing... I'd also want stainless steel exhaust valves or hardened exhaust seats. I'd skip the headers and run the Charger single 2 1/2 exhaust system. Those little engines were bullet proof and plenty quick. Automatic transmission?
 
I would consider it equal to or better than a commando engine minus the dress up kit. Valve covers and air cleaner. It has a larger displacement and similar cam, pistons and carb and includes the original commando intake in addition to the Ld4B. The port matching is a nice plus the head work with the slightly larger valves than a stock 2 bbl.
 
All the really cool and expensive Charger, since we are talking Dart, stuff is missing. Pretty hard to get a better distributor than a cast iron Prestolite distributor with the right curve and ball bearing vacuum advance plate. I have run a 284 duration cam in a 273, and found a smaller cam is much better all around, unless you want to make a drag racer out of it. Is that a solid lifter cam? 1.88 intake valves get real close to the cylinder wall, I hope he knew what he was doing... I'd also want stainless steel exhaust valves or hardened exhaust seats. I'd skip the headers and run the Charger single 2 1/2 exhaust system. Those little engines were bullet proof and plenty quick. Automatic transmission?
Good point it may have started out as a Commando engine unless I am reading the post wrong... but now that it is going into a Dart...It would be a Dart Charger application
 
Agree, there is nothing "Commando" about this, just a standard 273 built up, may have started as a "Commando" but like said, without the intake and valve covers it might as well be a standard 273.


Alan
Seller says they have the original intake
 
All the really cool and expensive Charger, since we are talking Dart, stuff is missing. Pretty hard to get a better distributor than a cast iron Prestolite distributor with the right curve and ball bearing vacuum advance plate. I have run a 284 duration cam in a 273, and found a smaller cam is much better all around, unless you want to make a drag racer out of it. Is that a solid lifter cam? 1.88 intake valves get real close to the cylinder wall, I hope he knew what he was doing... I'd also want stainless steel exhaust valves or hardened exhaust seats. I'd skip the headers and run the Charger single 2 1/2 exhaust system. Those little engines were bullet proof and plenty quick. Automatic transmission?
I have a 904 that was attached to the 273 garbage block that was in the Dart when I bought it.
 
-
Back
Top