318/340 questions please help!!

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Moose

Moose

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So heres my question whats the difference between a 318 and a 340? It cant be that much right? Cause there both small blocks and very close to the same look. And heres the other question, Could I take a 318 and make it into a 340? If so how?
thanks
 
Boresize, heads, cam, intake, sometimes forged vs steel crank

If many, most, all, 318's could be bored to 340, then many many people would be doing it.
 
There are people doing it....

The real diff between a 318 and a 340?

Cubic inches........ and a motor mount

A few more IQ points out into a 318 will make it run harder than a 340 with a few less IQ points put into it............

340 heads can be put on a 318......

Most here will say how a 340 will make so much more power, blah blah, but were talking 22 inches, not say 122 inches like a 440. I'd build a old 318 first, anyday. But thats just me.
 
dodgetkboy78 said:
There are people doing it....

The real diff between a 318 and a 340?

Cubic inches........ and a motor mount

A few more IQ points out into a 318 will make it run harder than a 340 with a few less IQ points put into it............

340 heads can be put on a 318......

Most here will say how a 340 will make so much more power, blah blah, but were talking 22 inches, not say 122 inches like a 440. I'd build a old 318 first, anyday. But thats just me.
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What do you mean by IQ points? Sorry new into engine building. And how would you build a 318? Im looking for 350 to 400 ponies.:-D
 
Stock to stock or modified similarly a 318 will NEVER touch a 340..remember 340's were only placed in performance applications..318,s were put in everything from trucks to taxi cabs hense the term "boat anchors"...
 
IQ points means don't listen to stroked 340...................

440's were put in everything from trucks, to taxicabs too! GASP!

22 cubic inches, and very similar torque curve. The 340 will make a bit more power, because of it's size, but if you don't have a 340, a 318 is easier to get....

So, basically, power wise, the 340 was given a bigger bore, thats all, same crank, same rods, same bearings, same timing covers, heads aren't an issue, ho hum....

350-400HP 318's are built every day.

1wildncrazy is good at typing in the details, im sure he will chime in soon, before I have to.... LOL

Your best bet would be to tell us what the car is, what gears are in it, auto or stick, tires, what you want to do, and what you have...... Then we can have a better idea of what to say.
 
stroked 340 said:
Stock to stock or modified similarly a 318 will NEVER touch a 340..remember 340's were only placed in performance applications..318,s were put in everything from trucks to taxi cabs hense the term "boat anchors"...
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A term only used by you here and one I never hear anywhere in the real world. Words you use so much, you must say them in your sleep. Words that don't help the OE poster and his question in most threads you post in.

Do you think you could actually help for a change?

dodgetkboy78 said:
IQ points means don't listen to stroked 340...................
Click to expand...
And hitting the nail on the head again..........TK!
And hitting the nail on the head again.......440's were put in everything from trucks, to taxicabs too! GASP!.
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Excellent point in case.
 
Moose said:
So heres my question whats the difference between a 318 and a 340? It cant be that much right? Cause there both small blocks and very close to the same look. And heres the other question, Could I take a 318 and make it into a 340? If so how?
thanks
Click to expand...

The main difference between the two are;

Bore size
Crank material, cast vs. forged

Then the things that make it perform;

Pisons comp. ratio
cam
exhaust
heads
intake
carb

There the same engine block in it's physical outside dimentions, thats why they look so similar.
 
don´t forget the motor mount, I had bougt a conversion kit for installing a 318 in slantsix mounts,but the company where i order it, they had the mounts for a 340/360,so don´t forget that
 
Ok, 340's have a bigger bore '68-'71's came with forged pistons,forged rods,forged cranks,bigger cams much better flowing heads 340's only came with a 4-barrell or 6-pack induction and were underated h.p. wise anyone that has owned one knows that 275 was a joke number and yes the 22 c.i. is a big deal...performance wise i've NEVER seen a 318 beat a 340 in naturally aspirated form,not saying a 318 can't beat a 340 but you'll put more into it to do so...
 
stroked 340 said:
Ok, 340's have a bigger bore '68-'71's came with forged pistons,forged rods,forged cranks,bigger cams much better flowing heads 340's only came with a 4-barrell or 6-pack induction and were underated h.p. wise anyone that has owned one knows that 275 was a joke number and yes the 22 c.i. is a big deal...performance wise i've NEVER seen a 318 beat a 340 in naturally aspirated form,not saying a 318 can't beat a 340 but you'll put more into it to do so...
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And to think the biggest HP of all A engines was a 318 from the 50's......

340's came with forged rods and 318's came with.............
More 318's were built with forged cranks than there were 340's made, LOL...

Cams, heads, are a noot point, because they interchange.....

Lets try again......

22 cubic inches, dictated by bore size, and a motor mount..........

Say it, repeat after me.......


To the original poster, what do you have, and what are you trying to accomplish?
 
Check out Tim Bowman Performance as he scheduled to build my 440 next year. You can make a 318 into stroker 390 and a 340 into a stroker 416. I had my 340 stroked in the spring and I do not regret it althought the engine was numbers matching:

http://www.bowmanperformance.com/

Mark
 
Like most said already, the 340 had a bigger bore, lager valves that opened to bigger higher flowing ports, larger rods, floating pins [same as early 273/318], a windage tray, beefier main caps, side webbing increase in 1970.

Basically some of the things they improved [rods] or thought was an improvement were also then phased into the other small blocks. I think the lil beaker floating rods are fine for a 273/318 and the larger ones probably aren't needed, just extra weight in the rotating assembly.

as for 273/318's, the ideas with floating pins,steel cranks were already incorporated long before the 340 came a long, it's evolution baby.
 
How would I build a 350-400HP 318......

HEHEHEheheheheeeeeeeee!!!!!!!!!!!!!!!!


Stock 318 Block, decked, squared, checked.
4" crank/piston/rod kit.
Good ol set of early big port heads.
cam in the 270adv range.
Performer RPM.
750 EDEL carb.....

Pretty inexpensive, decent street manners, and FUN FUN FUN!
 
I have a 71 duster that came with a 318 and a 727 it has 8 3/4 sure grip it what I was told. Basicly Im looking sleeper/nice streeter, something that isnt over the top just nice power. So I thought 350-400 hp was good but I dont know, your thought would help lol
Thanks guys
 
A bunchof guys posted, "Do a stroker" route. Is that an OK idea for you?
 
Moose said:
I have a 71 duster that came with a 318 and a 727 it has 8 3/4 sure grip it what I was told. Basicly Im looking sleeper/nice streeter, something that isnt over the top just nice power. So I thought 350-400 hp was good but I dont know, your thought would help lol
Thanks guys
Click to expand...

Check it, make sure it is a 727.


if the stroker is a route you might want to take, it's the easiest way to get streetable 400HP's......

If not, we will need to further investigate what exactly you want to spend, your abilities, etc.

And watch out for rumble, he was kissing MY *** earlier...... I think he may be ill!

hahahahahaaaa
 
Moose said:
What do you mean by IQ points? Sorry new into engine building. And how would you build a 318? Im looking for 350 to 400 ponies.:-D
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Lots of answers, The best thing to do is just buy my 318. With headers will be around your 350 hp range. It has a 340 grind purple cam and 9.5:1 compression. less than 1200 miles on it. You could put new cam and change thing up aliitle. MSD not included. $1400 below link to burnout with the engine! lol

[ame="http://www.youtube.com/watch?v=0EBEvNxtUUk"]YouTube - 72 Duster 318 burn out[/ame]
 

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rumblefish360 said:
A steeeeeeeal

Wheres Dixon located?
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It's in IL about 80 miles due west of Chicago. It is a good deal. Not trying to steal the thread. Just an offer to the original poster. If he does'nt want it, I will post on the For sale fourm.
 
If money is not a huge factor I would bore and stroke the 318 to 390 and change the cylinder heads with 5 axis ported ones from Indy Cylinder Heads. A cam shaft from Lunati and a stroker kit from Muscle Motors, RPM Machine (I have theirs), or 440 Source, ect. and 400 horsepower will be easily achieved as well as a lighter wallet and bank acount. Now you will need to upgrade the stock exhaust manifold with TTI exhaust headers and system (3" x pipe on mine) as well as your brakes.
 
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