Dartswinger70
Well-Known Member
Gee I'd love to get roped into an argument wit ya but...Ill just cut it short by saying I have 2 340s so there... nyahhh...
273 or NOT 273?
- Thread starter 67_Slimer
- Start date
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Don't forget/ If you do, we will remind you.Gee I'd love to get roped into an argument wit ya but...Ill just cut it short by saying I have 2 340s so there... nyahhh...
Just remember, the 235/273 had more horsepower/cu. in. than the 340.Gee I'd love to get roped into an argument wit ya but...Ill just cut it short by saying I have 2 340s so there... nyahhh...
(I know, it's all about how it's rated)
67_Slimer
Real Hot Rods don't shift themselves.
So do I but just trying to make a point.Gee I'd love to get roped into an argument wit ya but...Ill just cut it short by saying I have 2 340s so there... nyahhh...
Dartswinger70
Well-Known Member
You are talking about teh commando? the interwebs says this: The 273 (4.5 L) was the first LA engine, introduced in 1964 and offered through 1969, rated at 180 BHp.Just remember, the 235/273 had more horsepower/cu. in. than the 340.
also I have understood that a 273 was is about the same as a base 318 or id concede 185--230 HP. Now a 340 can be tuned to right about 330-340 HP. Nicks garage spun one recently to
335 horse i think it was. I do enjoy the "little engine" arguments on here but i try not to get roped in too far with it.
The 340 comment was a "yeah well my dad is bigger than yours" playgroundreference...
Dartswinger70
Well-Known Member
I get it its all good. I know about the commando, thing is not all 273s are commandos. I'd bet they are as rare as the 340s.
The 273 4 barrel that was in production between 65 and 67. Rated at 235 horse. Then of course there was the 275 horse D dart engine in 66.You are talking about teh commando? the interwebs says this: The 273 (4.5 L) was the first LA engine, introduced in 1964 and offered through 1969, rated at 180 BHp.
also I have understood that a 273 was is about the same as a base 318 or id concede 185--230 HP. Now a 340 can be tuned to right about 330-340 HP. Nicks garage spun one recently to
335 horse i think it was. I do enjoy the "little engine" arguments on here but i try not to get roped in too far with it.
""Tipping the scales at slightly over 2900 pounds, the 275-horsepower Dart fell into NHRA's D/Stock category-thus the car's appropriately fitting handle. Underhood, aftermarket parts included a 284-degree, ½-inch-lift Camcraft camshaft, Racer Brown valve springs, Doug's headers and a 4160 Holley carb adapted to the stock 273/235 iron manifold. A New Process A-833 4-speed gearbox was twisted by Weber clutch components and smoothly shifted by way of Hurst. Underneath, a "big car" 8¾-inch rearend carried a Sure-Grip center section and standard 4.86 gears. About the only items that this fleet factory rod didn't come with were air conditioning and a warranty."" (from an article in Hot Rod Magazine.
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Dartswinger70
Well-Known Member
Yeah 318 was the same at 235 horse I recall but then became a smogger in the early 70s as well as 340 and 360. were smogified. The later 340 was rated 235
Ha! All 3 were rated 235 at some point. 
I sell engine parts all day long and I am never going to tell a guy what he should buy, but I do make suggestions based on what I do know.
Just an FYI: All of my kits that I sell I use King XP bearings in. You can no longer just buy a regular XP bearing for the small journal crankshaft mains. Because they just don't offer them.
You can still get them non coated for a 360 because they still sell the volume. The small journal bearings are now only available in the coated version which cost double.
I also try to convince my customers to build engines that use readily available, off the shelf parts that will still be available down the road (or at least we hope)
For what it's worth one of the best running SBMs I've ever driven is a 380" 360 with ported iron heads, a ported iron 340 intake, and a smaller AVS. It will not hook up on street tires.
If you have good ring seal, a quality valve job, and a reasonable cam they will all give you a smile on your face when you stab it to the floor. One should always build what they want,
but smaller bearing and smaller bore engines are going to cost you more in today's world. Building an engine with at least a 4.00" bore gives you the most piston options available at the
most reasonable cost you can get, and the highest availability. Most of us work everyday and aren't sponsored in our racing efforts. Parts go up 5%-6% every year, engine building is
getting to the point most can't afford it any longer. That's why I advocate a careful selection of parts that provide the most cost effective solution to ones wants.
On with the 273 or Not.
Tom
Just an FYI: All of my kits that I sell I use King XP bearings in. You can no longer just buy a regular XP bearing for the small journal crankshaft mains. Because they just don't offer them.
You can still get them non coated for a 360 because they still sell the volume. The small journal bearings are now only available in the coated version which cost double.
I also try to convince my customers to build engines that use readily available, off the shelf parts that will still be available down the road (or at least we hope)
For what it's worth one of the best running SBMs I've ever driven is a 380" 360 with ported iron heads, a ported iron 340 intake, and a smaller AVS. It will not hook up on street tires.
If you have good ring seal, a quality valve job, and a reasonable cam they will all give you a smile on your face when you stab it to the floor. One should always build what they want,
but smaller bearing and smaller bore engines are going to cost you more in today's world. Building an engine with at least a 4.00" bore gives you the most piston options available at the
most reasonable cost you can get, and the highest availability. Most of us work everyday and aren't sponsored in our racing efforts. Parts go up 5%-6% every year, engine building is
getting to the point most can't afford it any longer. That's why I advocate a careful selection of parts that provide the most cost effective solution to ones wants.
On with the 273 or Not.
Tom
Dartswinger70
Well-Known Member
Ok I'll tell a 273 story. It was the 80s I was maybe 14 or 15 but knew what I thought I knew about cars, anyway there was a guy in the neighborhood with a 66 barracuda, keep in mind this is when the car was maybe 19 or 20 years old. He had the hood up...I walk over a clueless punk that I was and probably said "what's it got in it...?" the guy said "273" I was like "273? what is that...?" and he explained. the guy was probably 20 years older 33 or 35 etc. but that is the first id ever heard of 273. In the 80s the big Mopar was 383, 440, 340...318 etc. Chevys were 327 350 400 396,454... Ford was 5.0 , 351 Cleveland, Windsor, Modified etc. 273 to me was an odd ball never heard of it.
273 I have no problem with any of them but Id build it with realistic goals. I'd redo a 273 to put in a 66 Barracuda and probably stick to stock specs and expectations. Tune it well see what it does in street dress etc. I actually was looking at a 65 Barracuda maybe 6 years ago they guy wanted 5500 but it disappeared. Not sure if they are going that affordable now.
273 I have no problem with any of them but Id build it with realistic goals. I'd redo a 273 to put in a 66 Barracuda and probably stick to stock specs and expectations. Tune it well see what it does in street dress etc. I actually was looking at a 65 Barracuda maybe 6 years ago they guy wanted 5500 but it disappeared. Not sure if they are going that affordable now.
I have three 340's. They are waiting till I get bored with the 273. So far the 273 has been in one of my Barracudas for 50 years and still the 340 just sits on the engine stand...Gee I'd love to get roped into an argument wit ya but...Ill just cut it short by saying I have 2 340s so there... nyahhh...
mygasser
Well-Known Member
nobody mentioned the hp of your 340 except you. if the second comment was aimed at me i've been building engines for myself and freinds for 40+ years so ignorant i'm not
. saying a stroker will rev to 7k was just a comment based on your 'want' for a high revving small block that inferred a stroker then wouldn't/couldn't be high revving. my point was with parts matched to each motor's size the bigger one will make more power and at high revs if that's how you want/build it. i'm glad we don't all build the same thing or it'd be pretty boring. back to the start here, given the choice (if i had both) i'd build the 340 rather than the 273 purely on the basis of bang for the buck. good luck with it whichever you choose to build.neil.
Dartswinger70
Well-Known Member
Correct me if Im wrong but isnt the parts selection for 273s limited? things like gasket kits that don't work or aren't available? OR is it true that a fel pro gasket kit is out there for 273? i think in terms of overall headache on a build .
67_Slimer
Real Hot Rods don't shift themselves.
I already looked into it and decided to build another 340.
Dartswinger70
Well-Known Member
Yeah I mean I have nothing against any of the LA engines but I know or think 273 stuff is limited availability wise etc. and who knows going forward alot of it may be I'm sad to say.
You are misinformed. 273 uses everything the same as a 318 or 340 except pistons and rings.
Gaskets really aren't an issue. 273/318 gaskets are interchangeable except for the original steel shim head gaskets which aren't made any more. More Information for FEL-PRO FS8553PT9
The PT head gaskets in the kit will work fine. I used these instead. Thinner and just a bit smaller bore. There are always Cometic gaskets as well. DODGE Mr. Gasket 1121G Mr. Gasket Head Gaskets | Summit Racing
Unless you got great cylinder heads lot of them peak before 6000 rpm and hp quickly declines after the peak (falls off a cliff).
the Teen was 230 horse.Yeah 318 was the same at 235 horse I recall but then became a smogger in the early 70s as well as 340 and 360. were smogified. The later 340 was rated 235
| USA specifications | 273 V8 | 318 V8 (LA) | 340 V8 |
|---|---|---|---|
| Gross horsepower, 1968 (1962 for 318-A) | 190 @ 4400 | 230 @ 4400 | 275 @ 5000 |
| Torque, lbs.-ft. , 1968 | 260 @ 2000 | 340 @ 2400 | 340 @ 3200 |
| Compression ratio, 1968 | 9.0 to 1 | 9.2 to 1 | 10.5 to 1 |
| Bore, inches | 3.63 | 3.91 | 4.04 |
| Stroke, inches | 3.312 | 3.312 | 3.312 |
| Carburetor type (1968-73) | 2-bbl. | 2-bbl. | 4-bbl. |
| Fuel | Regular | Regular | Premium |
The chart needs a tune up. The 273-2 barrel was rated at 180 not 190. There is no specs for the 273-4 barrel which was rated at 235 horse and 260 lb/ft of torque. Now look at the 318, 5 horse less than the 273-4 but 340 lb/ft instead of 260 for the 273. (and at a lower rpm with the 318)
| 1967 283 V8 | 2 barrel | 4 barrel |
|---|---|---|
| Gross hp (Valiant) | 180 @ 4,200 | 235 @ 5,200 |
| Torque (Valiant) | 260 @ 1,600 | 260 @ 4,000 |
| Bore and Stroke | 3.63 x 3.31 | 3.63 x 3.31 |
| Compression Ratio :1 | 8.8 | 10.5 |
I wish the police pursuit 318 4bbl would have been rated in Gross... I drove one all original in a Volare, it honestly was one of the fastest stock LA's I've driven.
Mid to late 80's? Roller cam engine with 302 heads?
TQ, cast intake, 360 heads from the factory. Honestly, when i test drove it and punched it me and my brother were both surprised.
Say it ain't so, not with that super low cr
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