"That thing gotta 273?"

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You guys crack me up.
a 235hp 273 is rated .861 hp per cube
if you want to compare it to another engine, then to be fair, you will have to build them all to the same output; so
a 318 comes to 274 hp.
a 340 comes to 293hp,
a 360 comes to 310 hp
The hp jumps are 39,19,and 17, so
The biggest jump of all is from 273 to 318.
Then to be fair, again, stuff them all, one atta time, into the same 3400 car and take it for a spin.
Guess what, the 360 makes the same power as the 273-4bbl but it does it on just 6 cylinders.....

But to be really fair, you gotta look at the sub-3600rpm torque curves cuz that is where a streeter spends most of it's life. And when you do that, the 4bbl 273 is in a world of pain, comparatively speaking.

I get so tired of hearing this argument, especially in a street car with street gears. Or gears to cruise at, in the range of 2000 to 2400 rpm. That will take 2.94s to 2.73s, which will relegate the 4bbl-273 right into the realm of also-rans.
 
You crack me up. Why limit myself to 3600 rpm. I'm not driving a tractor. My 273 was never shifted below 3,000 rpm. We are not building anything. What came stock, what are your components? What is high performance and what is low compression so-so. Not comparable. High performance wins. I hate to tell you, but I can, and have had almost all MOPAR engines, from stock to high performance, didn't save any 318's or 360's. If I go bigger than a 340 it will be a big block, internally balanced. How fast do you want to go? How quick do you need a street car? I'm good to go. I can make anything do what I want, including a 170/6. My last car will be a 273, 4 speed, 66 Barracuda. I just love how it runs. No it is not stock, but mostly.
 
I think AJ's point is that the larger motor will have a much stronger low and mid range than the 273. Also more power, too, all other things being equal. I know that theoretically peak power is set by induction/exhaust flow, so that a smaller engine can make just as much peak power as the larger motor, only at a higher rpm. In reality, as I understand it, even at peak the smaller engine will fall short for various reasons that I think include higher internal friction from higher rpms. At any rate, even with the same peak power, the larger engine will feel - and be - much stronger with street gearing as it will have much more power under the curve.

It is also noteworthy that a 273 is not an especially short stroke engine - it has the exact same stroke as a 318 or 340. So it has no advantage in piston speed or revvability over its larger cousins.

I had a 273 and it ran well, but it was a hell of a lot stronger when I put a 340 in it. And that's with both motors running the same cam.
 
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When someone has not run the different motors, and wants to do math exercises, things are not linear nor the same. I had a 71 340, 4 speed Duster. It was fast, and I still have the 340 and 2 others, as a backup if the 273 ever fails. But if you set any small block up with the same heads, intake and carb, they will run very much the same. The peak rpm drops as the engine gets larger. The limiting factor is the "safe" rpm. about 7,000 rpm with a good small block bottom end.
 
Yes I always get asked if mine is a 318. When I say 273, the older guys will atleast remember oh those had solid lifter cams.
And then you tell a unsuspecting motorhead about the 273-4 barrel engine and their eyes light up. Lots of performance goodies from the factory.
 
And then you tell a unsuspecting motorhead about the 273-4 barrel engine and their eyes light up. Lots of performance goodies from the factory.
I think it’s one of Chrysler’s best dressed engines.
3B251F39-9DDF-4ED8-B516-3FBEC6D8725A.jpeg
 
well, no one has ever asked me if that's a 273. i think we're the only ones who know they exist.

Well, they did stop making them FIFTY years ago (as hard as that is for me to believe).

In a similar vein, people have mistaken this for a poly 318, but nope - it's a 277 (factory four barrel and dual exhaust, but the carb and air cleaner are not original). Looks just like a 318 poly, but it's not.

277 with Edelbrock.jpg
 
The hi-po 273 chrome air cleaner has always been one of my favorites. It's a bit small for the 340 that's in my 65 Barracuda, but just right for the 277 in my 56 Plymouth.
 
Talking about people thinking a 273 is a 318, I just remembered that back in the late eighties or so my wife and I looked at a 66 Barracuda for sale, thinking it might be a good car for our son. It was kinda dirty and faded, but really not a bad looking car - could have been nice with a little elbow grease. The seller said the motor was a 318. I told him no, if it was the original motor (and it was), it was a 273. He said no, it's a 318. I said no, it's a 273. Then he started shouting, "IT'S A 318! IT'S A 318!" We left.
 
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