Question about 340 vs. 440 (From newbie)

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Gold Crusader

Gold Crusader

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Hey guys,
I hardly know anything about engines and most likely won't be doing any engine builds or engine swaps for 1. not having enough room 2. and no time.

So, one day I'll be buying a Plymouth Barracuda or Roadrunner and dream about it every day.

My question is, what's the difference between the 340 and the 440? I mean, I know size-wise there's a difference, but can they be similar in speed?

From my little knowledge, I'm guessing they can be tuned to around the same power but the 440 had more potential. Why would anyone choose a car with a 340 rather than a 440? Better on gas?

How much heavier is the 440? Wouldn't that make a difference?

Sorry guys, pretty ignorant on all of this stuff. I know how knowledgable you all are so I thought you guys could help me.

Thank you!
 
To start, a 340 is considered a "small" block engine (as small as 273) and a 440 is considered a "big" block. All engines have great performance potential. However, not all engines are available from the factory in every body style. If you are considering a Barracuda, Dart, Valiant, these are called-"A" bodies, a smaller car. The most common engines found in these cars are the slant 6, a small V8 from 273 to 360, with some rare ones with 383,440,426 engines. If you are considering a mid-sized car like a Roadrunner, these are referred to as "B"bodies and include Roadrunner, GTX and Satilite. These cars could come with slant 6, V8's from 318 to 360, with some rarer ones having 383, 440, 426. On any car with a larger, "big block" engine be prepared to pay a premium price as these are rare and highly desired. For a small block motor to even approach the power levels of a big block requires much more than "tuning"- major engine components need to be replaced. At your skill level you should consider buying as much car that you can afford and just enjoy driving it.
 
How much power your looking for ? Is good street manners a concern, do you mind running deep rear gears and lot of stall ?

340/360 can make a good 350-450 hp add a 4” or go big block for 450-550 hp anything above that is generally big block territory. Obviously that’s not set in stone, you can build a 350 plus hp 440 for car if you wanted to would have the advantage of being more streetable especially if you put it on a diet.
 
Murray said:
To start, a 340 is considered a "small" block engine (as small as 273) and a 440 is considered a "big" block. All engines have great performance potential. However, not all engines are available from the factory in every body style. If you are considering a Barracuda, Dart, Valiant, these are called-"A" bodies, a smaller car. The most common engines found in these cars are the slant 6, a small V8 from 273 to 360, with some rare ones with 383,440,426 engines. If you are considering a mid-sized car like a Roadrunner, these are referred to as "B"bodies and include Roadrunner, GTX and Satilite. These cars could come with slant 6, V8's from 318 to 360, with some rarer ones having 383, 440, 426. On any car with a larger, "big block" engine be prepared to pay a premium price as these are rare and highly desired. For a small block motor to even approach the power levels of a big block requires much more than "tuning"- major engine components need to be replaced. At your skill level you should consider buying as much car that you can afford and just enjoy driving it.
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Murray summed it up pretty good. Weight difference I think is roughly couple hundred ponds
 
Murray said:
To start, a 340 is considered a "small" block engine (as small as 273) and a 440 is considered a "big" block. All engines have great performance potential. However, not all engines are available from the factory in every body style. If you are considering a Barracuda, Dart, Valiant, these are called-"A" bodies, a smaller car. The most common engines found in these cars are the slant 6, a small V8 from 273 to 360, with some rare ones with 383,440,426 engines. If you are considering a mid-sized car like a Roadrunner, these are referred to as "B"bodies and include Roadrunner, GTX and Satilite. These cars could come with slant 6, V8's from 318 to 360, with some rarer ones having 383, 440, 426. On any car with a larger, "big block" engine be prepared to pay a premium price as these are rare and highly desired. For a small block motor to even approach the power levels of a big block requires much more than "tuning"- major engine components need to be replaced. At your skill level you should consider buying as much car that you can afford and just enjoy driving it.
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Pretty much agree , the big blocks have a tougher time getting hooked up too .
 
I've run multiple darts with both 340's and 440's. They are both good. THe 440 is just easier and more street friendly. If I was soley concerned with handling I'd go with the 340. Other than that, the weight difference is negligible and I'd lean to the 440.
 
Drool over the unaffordable Big Block B & E -Bodies for a while . Then Buy and A-body. That is where you start. Work your way into a new Challenger that they will finance. Then when you retire get a vintage Six Pack or Hemi car. That is the car you admire and polish so your family can let it collect dust when you die.
 
340 vs 440 is the question. Both are good engines and are reliable. In their natural (factory) state, the 440 is going to offer more torque, and HP. 340 will fit better in A-bodies. With todays components available from heads to stroker kits, desired power ranges can be had with both motors. Why not throw the 360 in the mix? Much cheaper and easier to get than the other two, and the same can be said for the 360 as said about the 340. 360 and 340's look the same to look at.
 
The 340 was built as the performance motor for the 68 Darts and Barracudas. 1970 the plymouth Duster and the Dodge Dart continued to carry the 340 as the performance option. Great power to weight ratio and the price new was resonable . If you ever rode in a well tuned 340 A body youll know how they became known as "giant killer" & "big bore hunter". Big blocks were offered in the early yrs but had restricted exhaust. The 440 was not offered in the Roadrunner until mid year 69 and that was the 6 pack.
Just some info to answer the " how come"
 
Gold Crusader said:
Hey guys,
I hardly know anything about engines and most likely won't be doing any engine builds or engine swaps for 1. not having enough room 2. and no time.
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Keep reading and visit the web site “Allpar.com” for a **** to of reading.

So, one day I'll be buying a Plymouth Barracuda or Roadrunner and dream about it every day.

My question is, what's the difference between the 340 and the 440? I mean, I know size-wise there's a difference, but can they be similar in speed?
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Yes! They can for the most part, like 90% of the time.
BUT!!!!!
The larger the cubic inch displacement of the engine, the easier it is to get more power in both HP and torque. (Tq)
The big block has a great advantage over the small block in this department not only because of the obvious size difference in cubic inches but what it can also be equipped with and what naturally comes with. Bigger higher flowing parts. So that just makes more power easier and more streetable without being a snooty acting engine. Drivability goes up with more torque which is much more readily available and easier to make with more cubic inches. (AKA Big Block)

From my little knowledge, I'm guessing they can be tuned to around the same power but the 440 had more potential. Why would anyone choose a car with a 340 rather than a 440? Better on gas?
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In stock form, the smaller engine will get better mileage just because it is going to consume less fuel. In order to travel at 55 or 65 mph, the required power to move the vehicle is actually very low. The flip side of the coin to mileage is how effectively and efficiently the air and fuel is used and moved in and out of the engine coupled with lean mixtures and effective ignition burning all of the air and fuel charge.

Once you start “Hot Rodding” the engines, mileage drops and you’ll have to be careful of the parts chosen and decide on power or mileage.

The small block is generally cheaper to build and hot rod. But there is more than one way to skin a cat. Super Charging or Turbo Charging is one way to get more power without big cams and high compression pistons.

A lot of people like a small block because there light weight which helps make the car nimble for driving and quicker. A big block can loose a lot of weight with aluminum parts all over it. It can come down to right about a stock small blocks weight. So now you take the small block and add aluminum and it’s weight drops.

Small block, Less weight = easier to move & faster down the track.
Big block = more weight but much more power. More power, easier to move the car down the track.

A light weight big block can be nearly as nimble as a small block. I’ve seen them stand for to toe at the old local shoot outs around the cones. VERY exciting!


Sorry guys, pretty ignorant on all of this stuff. I know how knowledgable you all are so I thought you guys could help me.

Thank you!
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Yea man, no problem. Happy to discuss engines pretty much all day long.

In the end, when you finally get there, you yourself must be happy at the end of the day. Knowledge is power. Learn all you can and remember to keep an open mind. Not everything is in stone and cold hard facts. A lot is subjective and of personal taste. And that’s why we have some many choices. It is not a hat of one size fits all world.

My first little piece of advice is to first decide on what car you want. Then purchase the best example of excellence you can afford. Someone else’s project there tired of or a done and finished car as close to what you want already done.

If you want to learn how to work on cars, adult education classes or specialty trade school are a good start. Find someone working in there ride. Any manufacturer will do. Got a Ford friend? Learn stuff on his car. A lot will translate over. Buy a beater and tinker with it. Purchase books because there always at your finger tips for a quick reference and a permanent item. Start your library!

Also, make sure you have a two car garage at the minimum! And that’s just for the hot rod alone.
 
To the OP: What year(s) Barracuda or Road Runner are you thinking about owning one day? Will you be seeking an original car, or something modified? Those answers will narrow down what is likely to be under the hood of what you seek. For example - 68-69 Roadrunner standard engine was the 383, with the Hemi as the only option in 68-69 (until the mid year 440-6 in 69). The same years GTX standard engine was the 440 with the Hemi as the only option. Now if you want the last year Roadrunner trim in a Volarie body, we're talking 318 as the base engine. If modified is what you are after, just find one that looks good and kicks *** on the road and enjoy it.
 
Murray said:
...If you are considering a mid-sized car like a Roadrunner, these are referred to as "B"bodies and include Roadrunner, GTX and Satilite. These cars could come with slant 6, V8's from 318 to 360, with some rarer ones having 383, 440, 426...
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Just to clarify: All '68-'71 Road Runners came with a big block, 383s at a minimum. Minimum engine in as GTX was a 440. Later on they got small blocks.
 
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Personally I don't think it's a good idea to buy one of these cars not knowing a damn thing about mechanics. Things will go wrong and it will be hard to find mechanics that work on older cars. For instance my son is probably your age and is a ASE Certified mechanic at a Honda dealership. He's never worked on a carburetor before he wouldn't know how to work on your car... Remember to keep yourself a healthy budget for anything that goes wrong cuz you won't know what to do... my advice is to start finding people who know how to work on these cars and talking to them locally. Eventually you're going to need it...
 
Get one is Factory original as possible so you can get a book to fix it... if it's been customized to death you're going to have a hard time..
 
Using modern parts that are easily accessible a 440 fits very easily into an abody and TTI makes well fitting underchassis exhaust.
 
Good way to get your feet wet is a clean old 4 door with a slant or 318. It wont be somebody's haggard up rusty and rotten **** box you paid 200$ with big hopes and dreams..which usually ends up as a project that sits for the next 50 years.

I bought a pretty clean 71 more door valiant with a slant and learned how to stuff like drum brakes, head gasket and how a simple 1 barrel carb works and replaced strut rod bushings.

Now...I bull shitted you slightly. I started on a vintage carbed Yamaha motorcycle in 2007. But I did all that stuff with a manual and the skills have 100% transferred to the car stuff I listed above. But the valiant was my first old car. And it was an easy transfer from a carbed bike with points and a leaky head gasket
 
69_340_GTS said:
Just to clarify: All '68-'71 Road Runners came with a big block, 383s at a minimum. Minimum engine in as GTX was a 440. Later on they got small blocks.
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You sure about that?

71 is different!

71_Satellite_31.jpg


http://www.hamtramck-historical.com/images/dealerships/DealershipDataBook/1971/71_Satellite_31.jpg
 
Thank you guys! (Sorry for the late reply, been having family health issues).

It looks like what I need to do is just buy the car I truly want. I know the first thing I'll want to do when I get a Roadrunner with a 340 automatic is to make it a 440 manual. All of these answers helped me out tremendously. Thank you all
 
What year Road Runner are you thinking about?
Earlier models only had big blocks. IIRC
 
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