Information on a 340 for my 69 dart

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nutz

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i'm going to start looking for 340 stuff to swap out my225
want it to look 100% oe but not worried about date codes or stuff like that
i guess 340 were made 68 to 72 is there any thing i should look for (72 better then 68 ect.)
not going anything crazy want it to idle nice /stock exhaust /stock air filter
are all the sb sub frames the same (or do i need only 69)
i know its a lot to ask but i do see on fb market place stuff coming up and if something is local i might jump on it
is there something to stay away from
i'll start read threw the forums
thanks paul
 
340 was 68~73 early were forged crank and internally balanced, later were cast crank and externally balanced.

why not go 360? cheaper and easier to source, same price to build.

you'll need motor swap mounts to keep your slant six k-member (subframe), or you can swap the K to a V8 one and use stock 340 mounts.

here's the link for that: '67-72 A-Body Slant 6 to 273/318 or 340/360

you'll also need a whole mess of other stuff: transmission, radiator, some light wiring and obviously exhaust. basically none of the slant stuff crosses over.
 
Not sure what your budget is but it can climb up very quickly if you need everything from engine to trans and rear end. To answer your question about the compatability any 340 engine can be installed in your dart. There was a 66 dart here for sale with a complete 340 drivetrain you could transplant. Good luck with your project.
 
Get yourself a magnum 360 junkyard engine and a set of LA valvecovers, an aftermarket air gap intake, a cam, and a can of orange spraypaint. It'll look close enough and be faster.
 
Wouldn't want to go much over 15k.....but that's not even problem
A donner car is the way to go
Plans are to drive the car as is and collect body parts but if something comes up I'd jump on it
Has to be a basically stock 340 couldn't sleep at night with anything else
4spd thinking 373
It's a convert so just stock is enough
Want it look like it rolled out the factory that way
Seems like a early engine is better
But if something pops up anything will do
 
nutz said:
i'm going to start looking for 340 stuff to swap out my225
want it to look 100% oe but not worried about date codes or stuff like that
i guess 340 were made 68 to 72 is there any thing i should look for (72 better then 68 ect.)
not going anything crazy want it to idle nice /stock exhaust /stock air filter
are all the sb sub frames the same (or do i need only 69)
i know its a lot to ask but i do see on fb market place stuff coming up and if something is local i might jump on it
is there something to stay away from
i'll start read threw the forums
thanks paul
Click to expand...

I would get a 68-72 V8 K frame, 7/8 minimum torsion bars, 7/8 minimum front sway bar, lower control arms with sway bar tabs, and HD rear leaf springs. Start with a 318 short block (some early, 67-68?, blocks have very thick walls), get pistons to give you about 9.0:1 compression and run a high pressure oil pump and windage tray, Redo a set of 340 or 360 heads, next comes a 68-69 340 intake and AVS carb, get a curved distributor and electronic ignition kit, run a factory 340 cam and valve springs, run 68-70 340 exhaust manifolds and factory exhaust for a 69 Dart. You will also need good brakes (at least 10" drums), a 904 trans, and a HD rear end.
 
here are 2

www.facebook.com

Mopar 340, 1970, rebuilt, running

This is a rebuilt 1970 340 engine, casting date of 7-11-69. It has .040 over 10.2 compression pistons, steel crankshaft that is drilled for 4 speed. The heads are O & Z castings which are the same as...
www.facebook.com www.facebook.com

www.facebook.com

Rebuilt 1971 Mopar 340 HP

This is a rebuilt, running 1971 Mopar 340 engine. It's bored .040 over with 9.5 Speed Pro pistons, Crower Hydraulic cam with 480 lift 280 duration, J heads that have been ported with 2.02/ 1.60...
www.facebook.com www.facebook.com
 
The only way to tell the difference between a 340 and a 360 is to look at the side of the engine, behind the exhaust which is pretty tough when installed. The 360 will beat a 340 if built to the same level because u get an extra 20 cubic inches. And it is far more plentiful. FAR. Take a look around and you will see. The 340 gets its reputation cause the factory released it already pretty souped up.
 
I'd go looking for an 88-91(?) 360 for the roller cam and LA heads. Nothing against a Magnum 5.9, that would be the second choice. If I had to do it all over again today I would skip the 340.
 
dano said:
I'd go looking for an 88-91(?) 360 for the roller cam and LA heads.
Click to expand...
Thats what I did with my Barracuda. From an 89 Ramcharger.
Engine left.jpg
 
My only 2cents would be run the A833 overdrive, and combo it up rightly, cuz gas is never gonna be cheap again.
As for engines you would need one of;
a hi-compression LA318, or
a stock 5.9M
a lo-perf 340 or,
a more or less stock LA360. Any of these will get you the powerband you need to pull that overdrive box with 3.23s,
for 65=2100 rpm, yet have a nice starter gear of ~10/1. Which is more than you need in a lightweight-A with short tires.
_____________________________________

If you can afford the shipping, (about 1600 miles),
I got almost everything you need, from front to back, out of 67 to 73 cars, including;
any LA-SBM core, including 340s,
4bbl intakes and carbs, log manifolds, etcetera
any A833 trans, rebuilt or reconditioned,
Everything between engine and driveshaft; maybe even engine brackets
shifter, and pedal box (67)
any 67>72, 8.75rear end; core or reconditioned,
gears from 2.76 tp 3.23.
reconditioned SureGrip,
plus suspension/steering/brake parts, and
KH disc-brake system.
Missing would be;
a 4-speed tunnel/console/and reverse indicator.

Except;
the 360 is a 77 and is complete.
If you have a pre 67 car, they say my F-body od BH will not fit with factory available OEM Z-bar brackets. You would have to fab something up.
Also available ;
I have a sweet kitted A904 with a 2800 stall, that you would absolutely love.
Got some 14"wheels too; Rallys or Slot-Mags..
I'm yur one-stop shopping center.
 
69conv said:
The only way to tell the difference between a 340 and a 360 is to look at the side of the engine, behind the exhaust which is pretty tough when installed. The 360 will beat a 340 if built to the same level because u get an extra 20 cubic inches. And it is far more plentiful. FAR. Take a look around and you will see. The 340 gets its reputation cause the factory released it already pretty souped up.
Click to expand...
IMG_0993.jpeg
 
So think about how your reply is going to help someone not real familiar with engines, and may not want to do a lot of machining. Its obvious he doesn't have an unlimited budget cause he wants to gather parts. Hes swapping from a 225 3 on the tree. Lets hear it.
 
All I can tell you is good luck. Good 340 blocks are hard to find for a good price anymore. All of the parts are over 50 plus years old and most have had a hard life. I'm putting a 340 together now and it blows my mind what parts cost now and IF you can find them. Then machine cost has gone up as well. I'm afraid to add up where I'm at on this one but I can't stop now. I can tell you it way more than I was ready to spend. If you don't have deep pockets and you just want a good running V8 do a magnum and leave the 340 stuff for the restro guys. Or you could always hop up the /6 you have. They are fun tough engines that you can get good power out of. The torque they make is awesome. Good luck on your build.
 
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It's hard to put a budget on a dream
I have a euro auto shop so would rather spend the $$ to make it right
And always wanted a 340 dart
So here i am
 
Depending on parts selection, and what you get for a core, your all of 10k with buying the core, machining and parts, before you even think about putting it in the car. The BP crate is a good choice.
 
69conv said:
So think about how your reply is going to help someone not real familiar with engines, and may not want to do a lot of machining. Its obvious he doesn't have an unlimited budget cause he wants to gather parts. Hes swapping from a 225 3 on the tree. Lets hear it.
Click to expand...
It's not the budget right now when I do it I want everything ready to go so I can just swap it in a week or two ....I want to drive it
Body next winter then swap the following. I'm in the middle of the shop truck this year
 
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