Factory bored 340 vs. a bored 318

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STLUCIEAPPRAISAL

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I have a question. A customer has a 1967 notchback Barracuda in which he put a factory bored 340 motor which was, I believe, . In addition he put in a steel crankshaft, hi lift cam, headers, etc. which produced 400HP.

The motor is now shot and my customer plans to replace it with a 318 bored out to 340 and all the other stuff.

How much does the reworked motor lessen the value of his car vs. what it was worth with the factory bored 340?
 
unless it was the factory stock engine it doesnt make any difference aat all .by the way i'm pretty sure you can't bore a 318 to 4.04
 
The 340 was never available in a 1967, neither was a 318. The only V8 engines available were the 273 and 383 big block. A 340 engine is worth more than a 318 and more rare, so it would add a little more value to the car, but keep in mind the 340 was not original or factory to the 67 Barracuda.

Now, a person can stick the same money into both motors so for appraisal purposes i think the value would be the same and shouldn't matter much. It's just that some desire the 340 cause it was a performance engine.
 
At 3.91/318-4.04/340, the bore amount is to much to do.
Worth? Any worth for the car would need the OE engine. Once replaced, worth drops. A rebuilt OE engine is fine unless hi-po parts are added on. Then The value drops.
 
That's what I meant, the Barracuda model.

412 Stroker said:
True first year was 67, but the cuda only got the 273 or 383 like stated above.

[SIZE=+2]1967 Plymouth Barracuda[/SIZE]Production:
2D Hardtop Coupe: 28,196
2D Fastback: 30,110
Convertible: 4,228

Engines:
273 V8 180 bhp.
273 V8 235 bhp.
383 V8 280 bhp.
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You probably get around the same price but the 340 would make a quicker sale cause what would you rather have a 340 car or a 318 car, if your customer is a little shifty he could sale it as a 340 car anyway cause if you can bore it out to be a 340 than it is a 340 just not a 340 block.
 
Shoot, my apologies to everybody. I failed to mention that the 340 engine was from a later model, 1968 or 1969 according to the owner.

He feels that this factory bored motor, both from a historical and performance standpoint made his '67 worth more than had he just taken a worn 318 and had it bored, etc.
 
The 340 would be worth more because its a more "desirable" motor. How much more depends on the buyer. Ive seen 340 blocks as cheap as $250 and as much as $400 for just a bare block and thats really the only difference.
 
What year(s) 318 blocks can be bored from 3.910" to 4.040" (.130" over)? That's actually pretty cool if it can be done. I thought about .060-.080" was safe before you got too thin. I guess when you think about it though, .130" over is really taking .065" off the walls, and that's barely even 1/16 of an inch...
 
They say some blocks can go .100" over but you need to sonic check them to verify, Then you need to puy cu$tom pistons for it. Its not really worth the trouble.
 
The car with the 340 block in it will always be worth significantly more than with the 318 block in it. Unless maybe the 318 was stroked. I watch the market constantly and even 6 cyl. Bodies sell for much more with a 340 in them Vs. a 318.
 
Just a quick question. What exactly do you mean the 340 motor is shot? Did it throw a rod and bust the block? Or maybe drop a valve and done a bad job on the cylinder walls and heads? If none of these, I would rebuild and punch the 340 out and be done with it.
 
i am very interested
at this thread thx for Infos 318 bore to 340

What year(s) 318 blocks can be bored from 3.910" to 4.040" (.130" over)? That's actually pretty cool if it can be done. I thought about .060-.080" was safe before you got too thin. I guess when you think about it though, .130" over is really taking .065" off the walls, and that's barely even 1/16 of an inch...
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They say some blocks can go .100" over but you need to sonic check them to verify, Then you need to puy cu$tom pistons for it. Its not really worth the trouble.
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I think the truck blocks can be , can they not 68,69,70
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KT; All 318 engines are the same be it car or truck. Things like crank material or piston height change from year to year but otherwise, there all the same.

Sonic testing the block is the only way to know how far it will go.
 
OwdKasd, how much less in value, percentage-wise? If the car was worth $20K with the 340, how much with a bored 318 instead?

68DartProject, according to the owner, the shop screwed up the piston lock ring and destroyed the block.
 
I would say if its not an original 340 car it should not effect the value more then $1000-$2000 and thats being nice.
 
68DartProject, according to the owner, the shop screwed up the piston lock ring and destroyed the block.
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That is a shame. Seems like more and more folks popping up with a shop and don't know jack about anything. If it's not to bad he could have the motor sleeved, but you are talking a little more than he prob wants to spend.

I like the teen myself and with a .40 over taking it to 3.95 bore and putting the money into the top end he would still have a awesome ride. Being the car only came out that year with 273 and 383. I would think being he had the 340 in it, the value prob wouldn't change much. Maybe sell quicker but wouldn't think anymore.
 
STLUCIEAPPRAISAL said:
OwdKasd, how much less in value, percentage-wise? If the car was worth $20K with the 340, how much with a bored 318 instead?

68DartProject, according to the owner, the shop screwed up the piston lock ring and destroyed the block.
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I have seen non original 340 cars go for $5,000 more than very similar 318 cars. 25 to 50 % more. The 340 has a lot of pull for buyers. IMO a lot more than $1,000 to $2,000.
 
OwdKasd said:
I have seen non original 340 cars go for $5,000 more than very similar 318 cars. 25 to 50 % more. The 340 has a lot of pull for buyers. IMO a lot more than $1,000 to $2,000.
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I agree.Just the words 340 opens ppls eyes.When they hear 318 first thought is oh..ok.There is a stigma about small block mopars 318 was a gas saver with no power(although even stock they could run with the chevy and ford crowd),340 was the performance engine(for good reason) and the 360 was just a truck motor(no one gave them a chance).These views aren't mine but what I have experienced thru the years.
 
Think about it,the company advertised the 340 as top dog.How the owner probably bought the car.He is stiol looking upon it,as a investment partially.I would sleeve that 340,if it were my choice.
 
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