340ci vs 360ci SB performance engines

[Axels73Charger]

So I'm wondering which is better? The 340ci engine that came in the 73 Charger Rallye or the 360ci which replaced the 340ci in 74? Im trying to figure out which SB engine is the better performance engine because Im trying to make my search for a 73/74 Charger easier. So if I could get a 73/74 Charger that has a small block then I want to know which one is better so I can sell a 318 and put a 340 or 360 in it.

Also how much should I sell a 318 for? I want to maybe start out with a 318 then over time buy a BB rear end and put it on a SB car. Then after that I'll do a conversion from SB to BB later down the road but for now these are the questions im trying to find answers for.

[c00nhunterjoe]

the 360 will have more abundance of aftermarket cheap stuff, such as crate motors and such. the 340 wins on the "WOW" factor. if i built a smallblcok car it would be a 340

[RD]

340's cost too much, 360's will make more power for the same amount of money invested in either of the two, and your 318 aint worth that much, so if you were to get $200 for it, consider yourself lucky.

[craigandlynda]

the 360 has a larger diameter crank- is felt to be sturdier- i've used both, and feel more confident in the 360 for street use...remember tho, that when mating the 360 to a torqueflite or 4 speed, you will need to use the correct torque converter or flywheel- the 360 is balanced differently than the 318...if using an automatic, be sure to get a 727-A tranny...another beefier unit than the original 904 that came with almost every 318...

[craigandlynda]

p s- selling the 318? keep it so the buyer can hear it run, then be happy to get almost anything offered...$100 is a good price- or just keep it around for a "spare"  you or a friend may need for a daily driver some day

[Challenger340]

As far as a strictly "whats better" conversation goes, I think you need to realistically add the phrase "for a street application in a Heavier Car" ?
Lest we get bogged down in Bearing Speed, Balancing, Internal Dimensions & Square/Oversquare arguments, where the 340 clearly dominates over the 360 in higher rpm capabilities, that are more "Race" applicable.

IMO,
For "Street Stuff", No replacement for displacement, and Cheaper to build a 360 than a 340 pricewise, due to limited Piston availibility for the 340.
Pretty much anything you would do to the 340, also apply's to the 360 anyways,
so,
for most street stuff the 360 gets the nod due to the extra cubes, and more useable power per Dollar spent.

As mentioned, you will have to go to External Balancing to use the 360 versus your 318(Internal), so remember the weight on the Balancer and Torque Convertor.

Just an idea,
but if you are contemplating eventually going BB down the road ?
Have you considered just playing with the 318 for now in the interim, relatively cheaply of course to save money, until you begin the BB program ?
You might be pleasantly surprised at how well the 318 responds to Cam, Intake & Heads  ?

[Cooter]

Sh*t, a 318 is only a .130 under 340 anyway...I don't see WTF the big deal is with the 340...So it has a big bore, so what? Does that make it worth $1000.00 for a block? Nope, I can buy a 440 HP block for less....

360? Nope, had my dealings with those when I bored a 1976 360 out .040 to stock 340 bore and the cylinder cracked...
Had ALOT of hard earned money in the motor back in High School...

Built the hell outta a 340 after that tragic 360 deal..Got my ass handed to me by my brothers basically stock 440 in a 1969 Dodge Charger R/T...I had a 340, 727, 3500 Stall, 4.56 gear with Sure Grip, and a lighter car and he still got me by a full fender....

I swore I'd never build another small block again..All that wasted money only to get beat by a cheaper built 440...SO, I've been a 440 man every since...Now, all I use a 318,340,360 for is what they were intended for and that's getting from point A to point B.....

[Challenger340]

Sh*t, a 318 is only a .130 under 340 anyway...I don't see WTF the big deal is with the 340...So it has a big bore, so what? Does that make it worth $1000.00 for a block? Nope, I can buy a 440 HP block for less....

360? Nope, had my dealings with those when I bored a 1976 360 out .040 to stock 340 bore and the cylinder cracked...
Had ALOT of hard earned money in the motor back in High School...

Built the hell outta a 340 after that tragic 360 deal..Got my ass handed to me by my brothers basically stock 440 in a 1969 Dodge Charger R/T...I had a 340, 727, 3500 Stall, 4.56 gear with Sure Grip, and a lighter car and he still got me by a full fender....

I swore I'd never build another small block again..All that wasted money only to get beat by a cheaper built 440...SO, I've been a 440 man every since...Now, all I use a 318,340,360 for is what they were intended for and that's getting from point A to point B.....

Geez Cooter, THAT sucks !
Sounds like you had an awfull time with SB's ?

But, I think categorizing SB's a strictly A to B Engines is a little harsh ?
I always Raced BB's at the Track,
but,
I sure had alot of FUN spanking BB's on the Street with the SB's, and they were VERY reliable.



 

[Axels73Charger]

Well heres the thing I dont have date set on when im getting my 73/74 Charger and I dont have a date for the BB conversion either! Right now I kinda want to put something beafier in the car so I can still have some fun! What I want to do is 1) buy the car 2) put a better engine in 3) buy a BB rear end 4) buy a 440 and the mountings for a 73/74 Charger. Right now im only shooting for #1 but if I had the cash I was just thinking about it. Maybe I'll keep the 318 and by my dad his dream corevette and just buy the body then put the 318 in it But I really want to know options for a nice cheaper engine set up for a SB Charger.

[tricky lugnuts]

Stock, the 340 will be the stronger performer. That said, everything else for it will be more expensive, and aside from stock, the 360 has more cubes to play with...

Given the lower cost and larger displacement, I'd go with a 360.

That said, I ran a 1972 340 engine in my 1971 Charger for about seven years and eventually saved up the money for a complete rebuild. Ran great, pulled great... Loved it. Did a hell of a burnout, snapped your head back in the seat with the 3-1 downshift and got 17 miles per gallon. I drove it across the country with hardly a problem, from Ohio to California and back to New York.

That said, I sold my 340 to put in a stock 1971 440. I got the engine for about $500, minus exhaust manifolds. Put it in about four years ago and have been driving it ever since. It gets just as good mileage as the 340 - about 17 mpg "highway" - but the performance is much better. It's what a B-body is supposed to have, in my opinion. Rebuilding the 340 really woke it up. I can't wait to see what happens with the 440 when I finally go there. The beauty of it is, so far I haven't had to go there and it's 38 years old.

My advice? Keep running the 318, save the coin for a running 440 (forged crank, HiPo manifolds) and rebuild if you need one. The 440 is an awesome engine for bigger and heavier cars like the Charger. If you were getting a little A-body or E-body, I might recommend the 340.

[Axels73Charger]

Yeah I know B bodies should be BB cars but I trying to be money smart and almost all the BB cars cost too much and are most of the time in really bad condition. I've found more SB Chargers and some that are in good condition and are almost driveable which is what I want. Im also thinking I should get a SB because im younger and I should let the older and more experienced get the big project BB cars. But thats just my on the whole thing. Hell I may get a chance at a good condition BB and maybe I'll take it. But it depends on location price and condition.

[Cooter]

Geez Cooter, THAT sucks !
Sounds like you had an awfull time with SB's ?

But, I think categorizing SB's a strictly A to B Engines is a little harsh ?
I always Raced BB's at the Track,
but,
I sure had alot of FUN spanking BB's on the Street with the SB's, and they were VERY reliable.



 

At the risk of Small Block VS Big Block VS Import here, I only know one thing when it comes to making big power realliably and that's that it is one helluva lot cheaper, easier, and REPEATABLE to make 550 HP with a 440 that it is with a 408 Stroker Small Block...
Yes, I have had bad experiences with the SB, but I've also seen a T**ota S*pra here make 1500 HP at the wheels for over 14 years...Anything is possible when you have the money to MAKE it possible..ME on the other hand, I build junk..I'm the guy you see in the pits with all the other guys standing round scratching their heads wondering how the hell that POS with a BB in it went that fast with iron heads....

[draftingmonkey]

Well, in my opinion you first need to decide what you are using the car for and how you intend to drive.  Racing everybody on the road to show who has the fastest car or just a cruiser for a weekend drive.  And, where do you want to drive, straight stretches of road where you can open it up or windy country roads where the extra weight of a BB makes it more challenging to drive and drops fuel mileage. If you want to drive long trips or daily a SB is usually easier on fuel than a BB and a SB has a little more room under the hood to work on. To give you an idea of the different weights in stock format:

Slant 6 --------------------------------------------525
273-340 -------------------------------------------525
360------------------------------------------------550
361-400 -------------------------------------------620
413-440 -------------------------------------------670
426 Street Hemi ------------------------------------765

I did all my racing on the tracks in my youth and don't have anything to prove to anybody anymore. But, I will admit I did replace the 318 in my '74 with a 340 about 25 years ago. If I were to do it over again I would probably just build up the 318, but that is just me. Hope this gives you something else to ad to your thinking.

[chargd72]

I did all my racing on the tracks in my youth and don't have anything to prove to anybody anymore. But, I will admit I did replace the 318 in my '74 with a 340 about 25 years ago. If I were to do it over again I would probably just build up the 318, but that is just me. Hope this gives you something else to ad to your thinking.

Finally, some encouragment on keeping my three-A-teen 

Axels73charger,
I think your mind is in the right place.  I'm currently building up my 318 just enough to get some respectable performance.  Once my car is running I can save money, do my reseach, then build up a BB all while getting some quality driving time.  I'm ok with just turning heads for a while.  Smokin everyone on the streets will all come in time.   

[694spdRT]

For a cruiser I would go with a 318 or 360 Magnum if starting from scratch.

[Axels73Charger]

Well a good amount of driving will be in the country and this will be a daily driver but I want a preformance too. But I've been reading and I think I'm leaning more for 300+ hp. Which is ok for now what I really want is around 400+ hp or 500+ but I'll let the 500+ be for the BB. 350 to 400 hp sounds good right? And I read something else about getting pretty good mpg with ok hp...

[200MPH]

 5.9 Magnum with a Carb,headers and intake will get you pretty close or better than 300HP and be pretty strong since it would not be pulling around a heavy A$$ Ram

[draftingmonkey]

Well a good amount of driving will be in the country and this will be a daily driver but I want a performance too. But I've been reading and I think I'm leaning more for 300+ hp.

How about a 400HP 318. http://www.moparmusclemagazine.com/techarticles/mopp_0409_318_engine_build/index.html

[elacruze]

I just bought a pickup with 318 so I've given a little thought and asked a few questions.

First, I have a 400 B sitting on an engine stand, needs only a carb and exhaust. I could drop it in...or build a 451 with parts I already have.

I remember my buddy's 318 2bbl '74 charger shutting down a lot more stuff around town than it had a right to, just because it was tuned right...no headers or cam...

So I decided out of curiosity to see what I can do on the cheap with the 318.

This is what Comp Cams' program spits out for a stock '68 318 with 500CFM 2bbl and stock manifolds with XE256H cam, which is close to the 340HP cam;
243HP and 323 Lbs-Ft is not to sneeze at.
Add headers and 4-bbl; 280HP/363Tq.
Add 302 casting heads; 298HP/370Tq.

<edit> somebody asked about the 340HP cam. I've added.
20-309-4 340HP grind; 310HP/361Tq.
The 340 cam makes about 10HP more peak, about 10Lbs-Ft. less torque peak. The torque curve is the same, but about 500 rpm higher. Maybe good for your car, not so good for my 4500lb pickup.

Keep in mind, this is only Comp Cams' cam chooser program, not a real dyno or even an accurate model. Just a comparison guide.

Not numbers to sneeze at, especially since parts are cheap, and can be installed individually or all at once. I spent a lot of time in the CC program, the XE256H came out on top every time in all three combos. All this stuff together doesn't come to $1000. Wait for bargains, might be half that.
My opinion is, after I make these changes to the 318, I probably won't care to do the work to swap in the BB until I blow the 318, which might never happen.  

[chargd72]

Thanks for sharing the edited cam spec.

Wonder if the 12HP added is worth the 9Tq lost...     

[elacruze]

Thanks for sharing the edited cam spec.

Wonder if the 12HP added is worth the 9Tq lost...     

.


I missed that cam until it was mentioned, I was looking at the Truck/4x4 cams and it wasn't listed. It's in the car stuff.

The 340 cam is nearly identical but for the torque range, up about 500 rpm from the XE256. Hard to say just from a computer screen, but it would probably be hard to notice the difference. Since my vehicle is very heavy, and I'll be keeping the stock manifolds (at least to begin with) I'll probably go with the XE256. The truck is a stick, but it is a truck and my girls will be driving it too, so I don't want something that needs any clutch. If I was putting it in a car and knew it was getting headers, I'd certainly go with the 340 grind.
The whole point of this exercise is to support the notion that modding a 318 can get you enough good times cheap to keep you happy while you spend the money getting the Big Block ready to put in.

Is anyone following this thread who has actually made these mods, and can share real world experience?

[440charger68]

i love small blocks hahah they lots of fun, heres a pic of mine just finished a partial rebuild or freshened it up whatever u want to call it 

[jobbless]

i just bought my charger and it is small block but that is about to change. soon to be 440 4 speed.   although i did just pick up a mild built 360 for the girlfriends demon. she says she has to have a 340. i suppose to keep the "340 cool" thing going. just big blocks for me though. until i find me a nice slant six driver. the 440 is a bit hard on the wallet for daily use...

[oldrock]

we just finished doing a full rebuild on my son's number matching 318 in his 72 charger. We did the full deal including machine work and all parts for under a grand. THe machine shop guy cranked the numbers and said we should be looking at around 300hp and over 300ft lbs of torque. Not a speed demon but a fun street driver. We had to chase down a major gremlin on our electricals after the engine install but now that we have it all sorted out, very happy with the upgrade.

[Challenger340]

IMO
I think it's REALLY important when Modifying Cars equipped with SB Engines, (moreso than a BB Build Obviously because of the Bigger Inchs and Torque down Low), to remember the Drivetrain application in regards to Gearing,Convertor, etc. to get the best response out of a mouse ?

SB's, especially the 318/340 stuff, is very sensitive to "overcamming" when Modifying, therefore really important to allow them to "Get a Run" at it, into the powerband of the Cam.
Once "there" and actually IN the Range of the Cam, even the 318's can be "fun" performers.
Nobody asked,
and just my opinion, but I'm gonna suggest a 500 rpm "cushion" off the Lower Number in the Cam Range on a Torque Convertor application ?
It's a tough sell I know,
suggesting here, when talking about "cheap" Mods to 318 Engines for a "little more power", that a Guy should go buy a T/Convertor that costs as much again as the Mods themselves, but, it REALLY HELPS, especially with the Heavier Cars.
No Matter if the Cam Description says "Stock Convertor" or Not, if you can add the extra 500 rpm stall, you'll never be sorry you did.