A833 OD 340 4x4?

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CirusP

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Hi all,

So, recently I had such a blast camping with my dogs (im on that age), that Im planning on changing my plans of a 340 street strip car to a street-very streetable-maybe off road-sometimes at a stop light go 400meters as fast as possible-kind of car.

I will be swapping the 360 i have for a 340 (I have a tired overbored low compression 360 van block that Im not in l0ve with and I have found myself a 340), and a833 OD.

So, my question is: is it just stupid? Or not so much but a little?
If a good idea: what would I need appart from high gears for power and the front Dana conversion? What Transfer case? divorced, not divorced, AWD or 4x4 etc

This car was driven in my dad's garage the same day I was born, so HELL of emotional attachment, in case someone will say "just get a 4x4".

Thanks!
 
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So what is the vehicle this is going into? Sounds like a truck but might be a car (or van)?
 
So what is the vehicle this is going into? Sounds like a truck but might be a car (or van)?

I wanted to keep it mistery as its not a-body; Its a Dakota 1988...

Thou I've cointemplated the idea of turning my 63 Dart into a 4x4, I know its been done before but....
 
While the 340 can be fun,
the 360 will have a whole big buncha more low-rpm grunt.
While at 3000 pounds the 340 would be more than up to it,
the 360 will be better at 4000.

400 meters is a very long way .
a 340 done up for that will NOT like the 3+1,A833.
Even the 360 at 4000 pounds will have trouble with that trans, with a cam of more than 223@.050
It's not the getting off the line that is the problem; rather, it's the 1.67 second gear that sucks.
With a 340;
Let's say you run 28" tires. And low gear is 3.09 so you want a starter of say 10 or 11 to 1. And that means you can run 3.55s. Which is a great starter gear; not too deep, and not too shallow, but perfect.
But with 3.55s, 65= 2000 rpm, so if fuel economy is on the table, this is borderline too low for the 230* cam your 340 is gonna want. With the 230 cam 3.91s is what she wants to cruise with. But 3.91s make a starter gear of 12.08, which means that the rpm is gonna climb very rapidly in first gear; annoyingly rapidly. And Bam! you will be in Second gear... typically shifting at say 3200/ 22mph(3.91s). But at 22 mph in Second the Rs drop to 1720rpm, so the 340 is way out of it's element, as in total lack of torque. But you say com'on, it's got 3.91s why is it so doggy?
Ok, the 340 with a 230* cam to satisfy your rapid transit to 400 meters, is gonna want to be up at around 3700 before she will deliver some power. In Second gear (1.67 x 3.91), this will be, wait for it..... 47 mph. So no matter at what rpm you outshift First, your 340 is gonna have to buzz up to ~4700 to find some scoot; and that's with 3.91s! To get 47 mph in First gear requires 6800 rpm. If you are running a 230*cam, it will peak around 5200 and you will shift it at around 5500, and 5500 with 3.91s is about 38 mph. On the 1-2 shift, the Rs will fall to 2980, again waaaay into the marshmallow zone. So now the 340 has to struggle up to 3700/47 mph. But 5500 in Second is 70mph. On the 2-3 shift at 70mph, the Rs will fall to......3300; let the struggle begin again. If your 340 equipped 88Dakota can hit 90 at 400M, that will be 4200, way down the power-curve.
So, like I said, Second gear is the problem. It's too far from first, and just as bad on the 2-3 shift. You can put Second Gear where ever you want with rear gearing, but that just messes everything else up.
Check this out. A good place for a streeter to be geared is 2800@32mph, in Second Gear. This is comfortable to cruise around on, and at the downshift into first, the truck will rocket forward.
With 3+1 box, this will require ~4.30 rear gear, and on the downshift, the Rs will jump from 2800 to 5200 right on peak power................... but you got only 300rpm to 34mph and then it's back into Second; that really sucks. Now;
With the Commando box, 2800@32 mph as before, will require a 3.80 gear, rounds to 3.73s, so 32 will be 2750, and on the downshift into First, the Rs will climb to 4420 (instead of 5200) and you can wind that up all the way to 5500@40mph, BadaBoom!
What about the 360?
Well the picture is a lil brighter. For the same 400Meter performance, you can run one size smaller cam. This will get you a double-whammy of more low-rpm power; Firstly the 360 has more by virtue of it's stroke, and secondly, the smaller cam can deliver more.
So now, maybe the torque comes in around 3400/43 mph.
But hang on, why are we still running 3.91s? The 223*cammed 360 does not need nor want them. 3.7s will do just fine. Even 3.55s.
So with 3.55s, 3400 will be , wait for it......48 mph. Chit with a capital-C.
I'm telling ya that 3+1 box is terrible for a hot SBM
I made that 3+1box work by running alloy heads and cranking the pressure to 185 psi. And it still sucked in my 367 with a 223@.050 cam, and worse with the 230@.050 cam.

My tip; Run the early Commando 4-speed and forget overdrive. It has the perfect Second Gear, and Third is right there beside it; and the 360 can easily pull the 3.09 gear with 3.55s. I'll bet the 340 will only be a lil softer on take off, running the same cam and same cylinder pressure.
Ok, now 3400rpm with the Commando, in Second gear, with 3.55s, is 41mph..... but, first gear will get you to 44mph at 5800, so BadaBOOM! The 1-2 shift at 3200(First), now gets you 24mph at 1990rpm, going into Second, that's 2mph faster and 270more rpm with 3.55s now, versus 3.91s with the 3+1 !! that's a mighty big win.

Here are the A833ratios, (with the 1 x23 input);
3.09-1.67-1.00-.73od ( 3+1 misery)
3.09-1.92-1.40-1.00 (Commando)
2.66-1.92-1.40-1.00 (standard box)
2.47-1.77-1.34-1.00 (the close-ratio T/A box.)
Now, plug in some rear gears, into this formula, and see what it takes to make you happy;

MPH= (RPM x TC)/( 1056 xR1 x R2)

Where TC is Tire Circumference which is; diameter x 3.1416
R1 is trans ratio
R2 is rear gear ratio
1056 is a constant that converts the resulting product into a simple speed number.

>Which engine you chose depends on how low a rear gear you are willing to run, how much tire-spinning you want to do, and how much you value low-rpm running on the hiway. As for the 400meters, either engine will get you there,in the same ballpark, depending on how you set it up.
>The 4X4 will suck some power too, so another reason to go 360.
>IDK what your gas quality is like in Costa Rica, nor at what altitude you are running, so that, if you cannot run high-pressure, points to the 360 again.
>Alloy heads will let you run 87E10 to at least 185psi in my experience, with full-timing.
__________________ opinion coming_____________
Don't buy into the 340 better than 360 hype; that is just not true. Combo for combo, the 360 will do anything a 340 can, but with more low-end grunt.
I bored mine out to 4.04 so now its same as a 340 except has a longer stroke. And I cranked the Scr up to 11/1, better than any factory 340 ever was; and no factory 340 ever pumped 185 psi. So my 367 is like a 340 on steroids, just what you Dakota needs.
185psi with a 223* cam is a flippin' tractor at low rpm, a powerhouse thru the midrange, and I set mine up to rev to 7200... jus cuz I like to hear it screaming.
My rig is 3650 with me in it, and she likes 3.55s, but likes 3.23s almost as much.

BTW;
that overdrive is "fragile" to say the least. I blew two of them up, just by accidentally slamming the trans into "fourth" which is easy to do with certain bigger number rear gears. And when it shatters it goes everywhere, including down between other gears and wipes the whole trans out.

Ok time to cut it short,lol
 
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If its a Dakota 4x4 you already have a platform for an OD and smallblock .
Why the 833? Just use the existing trany...
 
A 2wd 833 OD will do you little good unless you want to go out and find/ adapt a divorced transfer case "from out of something else." Years ago Advance Adapters did make a bearing adapter to convert some types of transfer cases into "divorced."

I don't see it. It's still 4 gears and if you have a 2 speed transfer and pick the proper final gears a conventional 4 speed would be fine.

or drum up one of the small Dakota 5 speeds used over the years, already set up to bolt to a SB / magnum and a Dakota transfer case. For the life of me I cannot remember, maybe a NV3500?
 
The 5.9M is a pretty good powerplant for a two-gear application, like zero to 60. It just needs the right stall and gearing to make it come alive. But for the 400Meter-Dash, yur right, the 360 in factory trim,will be a lil lazy.

Consider the crappy gearing with the 3+1 box and say 3.91s, here is the road gear progression; 12.08-6.53-3.91-2.85 Looking at the ratios alone, it looks like this would work decent with up to 31" tall tires. But like crap with 25s. The splits are .54-.60-.73
but consider the A500 with 4.10s
11.23-6.31-4.10-2.83 the splits are; .56-.65-.69
I set them up with the same 2.8 final-drives.
However;
the automatic has a Torque Convertor, with a continuously variable hydraulic multiplier that varies between up to about 1.8 to 1.1 or thereabouts.
And the greatest multiplication occurs at zero mph, with the least, at cruising.
Therefore at zero mph, your starter ratio could be 11.23 x 1.8=20.21 depending on the power in your engine at it's stall speed.
Of course, as soon as the truck begins to move this multiplier begins to roll back towards it's minimum ratio. But it will never get there in First gear.
Suppose the multiplier in first gear averages 1.35, then 1.35 x 11.23= 15.16
Suppose the multiplier in Second gear averages 1.25, then 1.25 x 6.31=7.89
Suppose in Third gear, the multiplier averages 1.15, then 1.15 x 4.10=4.72
in overdrive,
say the multiplier is 1.08,................ then 1.08 x 2.83=3.06
And in lock-up,
no multiplier at all, so........................................... 2.83
Ok then let's look at the big picture,
at WOT;
20.21-15.16-7.89-4.72-3.06-2.83
How many ratios is that?
I count Six.
Ok, 5.5, cuz that 20.21 is a split-second deal.

now, lets put some actual power into those numbers. Suppose your engine, whatever size it is, averages 360 ftlbs from stall to shift-rpm. lets multiply these ratios by that 360 to get an idea of what the axles are seeing;
First the 3+1,
12.08-6.53-3.91-2.85
4590-2481-1486-*** can't go WOT in od.
then the A500

20.21-15.16-7.89-4.72-3.06-2.83
7270-5458-2840-1699-1102-1019

These are ftlbs into the axles.
These numbers now have to be reduced to the equivalent of a one foot radius so we can see how much this will be to the road. So with 32s you would multiply these by 24/32; With 30s by 24/30; and with 28s by 24/28, and so on.
I'll let you do that math, because we don't actually need to know that, because this is a comparative exercise.

Obviously those first gear numbers will blow the tires off, The A500 maybe even all four of them.
I know which combo I would want, and the 3+1 is dead last in any game.
Now you just need a "big" TC, and yur all set.
 
So, Thank you all for the cpomments. The Dakota had in it a 4cyl at the begining, and a 5 speed. I swap.d it for a 360 I found here, and a 727 that came with it. But I have the a833OD which I thought to eventually swap for, you know, some mpg. The 340 is optional, and everything AJ said i (And geez, I thank you air for all the info, really), recon.

The main question was really if there was a possibility to have both worlds, the 4x4 world with a NP transfer case (and which would it be?), and the go-fast world.

The pick up is super cool as it is, and Im glad I found the 360, nbot only because the 4cyl was quite dead, but because its been an amazing platform to work with. I kinda just drive throu the mountains with it and my dogs in it and not get stuck in the mud with the 2wd. And the 340 well, it was just so cool to have an iconic engine.

Now, If I keep the 360 and put the OD unit (iron case), will it handle the power well? will I just be restricted to cruising?
I guess I could assemble the 340 and put it in some eventual project.

****More importantly, I HAVE all these things laying around, I want to use them, not get more stuff, I only have so much time and so much space.
 
While the 340 can be fun,
the 360 will have a whole big buncha more low-rpm grunt.
While at 3000 pounds the 340 would be more than up to it,
the 360 will be better at 4000.

400 meters is a very long way .

Thank you for all this info man!
 
You can drive the crap out of the first three gears of the A833od, but when you stick it in "fourth" you gotta remember to lift off the throttle. I forgot that twice, and each time it cost me a trans.

If you just wanna have fun, then the 360/5.9M/ 2WD/ 3+1 will provide that, but not with intentions of Rapid-Transit in the 400M. The gearing will be all wrong for that.

But you could stroke either engine, put an A518/ transfer case in it, and a quarter-mile friendly set of gears in it, that would do pretty good in overdrive.
Suppose you build a modest stroker that hits 105 in the quarter. This with 30" mudder tires would need 3.91s for 105=~5100 @ 10% TC slip
And 3.91s with 30s will cruise in OD at 65=1965rpm in lock-up, which with a 210ish cam, is just about the minimum rpm for fuel-economy. Of course a stroker with a 210 cam is pretty tame..... except when it comes to playing in the mud. And isn't that what you want?
I think it's probably overkill for that 88Dak, but that's how it works when you want to cover all the bases. 105 is plenty quick in the quarter, being about 340 hp at 3800 pounds, at sealevel. So that is a very modest build; 340/408=.83 hp per cube.My car got into the 12s going 105, spinning the 245/60-14 tires most of the way.
 
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I
You can drive the crap out of the first three gears of the A833od, but when you stick it in "fourth" you gotta remember to lift off the throttle. I forgot that twice, and each time it cost me a trans.

And is it possible to pair an OD unit to a transfer? Which one will it be best for it?
 
I'm not a truck guy, But I have never seen it in a Dodge. Someone here just mentioned seeing it in a chevy pick-up, so you can pirate that whole thing. But NONE of the chevy gears will mesh with any Mopar gears. So you would have to swap the Mainshaft and housing onto your Mopar box.
How would that work?
Awesome.
The normal 4-speed for this application is the NP435, but the splits in that box are real truck splits, meaning grain-truck on soft ground type splits. Not suitable for hi-rpm useage. The ratios are;
4.78-2.39-1.37-1.00 and
splits of .50-.57-.73
There is another Dodge ratio set, but it's even worse.

Somebody mentioned the NV 3500 5-speed. This has excellent ratios, but IDK if it is available with a transfer case.
The ratios are; 3.49-2.14-1.38-1.00-.73od. With
excellent progressive splits of; .61-.645-.725-.73
IIRC it is rated for just 300ftlbs tho, so forget the stroker. The 5.2M even makes more than 300......

But I got a question for you; keep in mind I have no experience in off-roading.
Say yur having a good time in Second gear in soft stuff, and suddenly the going gets tough in a hurry. How will you downshift fast enough to not get swamped? It seems to me that the instant you stab the clutch, it will be all over; am I wrong? It seems to me that this is where the auto and hi-stall would shine.
 
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But I got a question for you; keep in mind I have no experience in off-roading.
Say yur having a good time in Second gear in soft stuff, and suddenly the going gets tough in a hurry. How will you downshift fast enough to not get swamped? It seems to me that the instant you stab the clutch, it will be all over; am I wrong? It seems to me that this is where the auto and hi-stall would shine.

You are right. Im now convinced that I foolishly want it all in one car. Its maybe not possible, nor even a good idea. I'll leave it as it is.
Now, question. If i was to put a transfer case behind the 727, what would it be? Say. I could steal everything from a 4x4 Ram vehicle, I suppose, no?

It may be my nostalgia that's making a fuzz here...the dogs, the car, the mpg, the mountains and the beach... hahah
 
Now, question. If i was to put a transfer case behind the 727, what would it be? Say. I could steal everything from a 4x4 Ram vehicle, I suppose, no?
I'm not a truck guy, so I don't know the current designations. Back in the day, I worked for a company, and rebuilt hundreds and hundreds of transfer-cases for the army. There were just three kinds in those days; the NP 205, the NP 203, and some junky lil Jeep/Warner thing that I can no longer remember the designation of. One of those was an all gear deal. The other had a big old chain and a center differential that was used as a Power-Divider. The OEM chains were not strong enough in those days and quickly stretched out to make trouble. But that chain was quickly re-engineered, and the replacements seemed to survive; remember I built these for the Canadian Army with young bucks driving the crap out of them in training and such.
I think it was the 203 that had the chain and was the heavier duty unit, that you want.
But that was the 1980's.
IDK what's out there today.
Whatever you choose, make sure the dang thing has all mechanical levers on it and no electronic shift controls on it, which, IMO, suck. I hate those dash switches, that tell you what you have selected, but don't tell you if you actually got what you selected.
The problem is; if you pull all that stuff off a RAM, you might as well just drive the RAM, right? The later RAMs already comes with the hi-compression 5.9M powerhouse...........
And one thing that's been bugging me, is, you have not mentioned at what elevation you will be operating. This can be a really big deal as the elevation increases, and also if the truck needs to operate in a wide elevation change. Now yur looking at power-compensation that can only be achieved with cubic inches, and generally, with EFI, that has barometric compensations for ignition and fueling..
 
It may be my nostalgia that's making a fuzz here...the dogs, the car, the mpg, the mountains and the beach... hahah
Get a wife; she'll strangle all your truck dreams, and replace them with family responsibilities. Then you don't have to struggle with these types of decisions anymore. Twenty-five or thirty years from now, when your nuts are all dried up, your wife is pushing 200 pounds, and the last kid leaves home, you will have all but forgotten these youthful dreams.
On second thought................
 
It may be my nostalgia that's making a fuzz here...the dogs, the car, the mpg, the mountains and the beach... hahah
That's the second or third time mpg has come up. In which case forget the short-stroke 340. By the time you get decent power out of it, the cam is too big to make decent cruise economy. And if you build it for low-rpm torque, then it won't ET well in the 400M.
In this kind of environment you really need lots of gears, I mean like 5 or 6; then you can apply a smaller engine. Or next best, as I have shown you, is an automatic, with a "hi-stall loc-up Convertor", and an overdrive (like the A500/A518) that works as a 5-speed.
Failing that, you need a bigger engine, to cruise in direct with a low-number rear gear, and still have the low-rpm torque.
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For economy, the secret is to have a very small engine, operating at very low rpm, at very high efficiency.
For your truck, engine size range is about 2.5 liters(152 cubes), to 7.2 liters(440). Right in the middle is 4.85, so smaller than that could be considered "smaller" and bigger than that could be considered "bigger". The closest V8 (which has 4 power strokes per revolution versus 3 with a Six, which is 25% more, and you gotta have at least 4,lol.) to 4.85 is the 5.2/318. At 360/5.9 you are already over 21% bigger than the median, and 236% bigger than the 2.5........ So, fuel economy is fast slipping away.
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The 360/5.9 can be set up to do reasonably well in steady-state cruising, and it would be my choice for your application. With a two-speed transfer case, you can run hi-way gears, for fuel-economy, yet still have a 2:1 multiplier, turning say 3.23s to 6.46s in the mud. This will get you, at say 5000 rpm and with 30" tires, just over 60mph, in low range. And in hi-range those 3.23s in overdrive, will cruise at 65=1620 rpm with the 30s. That's pretty low; and to do it well will take a short overlap cam and plenty of matching cylinder pressure. But the thing is, now you have both low-rpm torque, and hi-efficiency, with an engine that is of a reasonably "small" size.
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So hang on a sec
if you had a 440 with say 480 ftlbs at 2000 stall, which would make a very fine 4X4 in high range,, how would that compare to your 360 at 2400, in lo-range? Well I'll bet your 360 with a tiny cam (to satisfy that 1620cruise rpm), would still make 340 at 2400. So in low range, that would translate to 340 x2= 680 out the transfer case.
Now, the 440 might use 4.30s, to your 3.23s so lets kill this coyote; for the 440; 480 x 4.30s makes 2064 into the axles, and for the 360; 340 x2 x3.23s is 2200....... a solid 6.4% more.
So, the bottom line is that you don't have to give it all away, you just have to choose your components carefully.
In your application, now that it is less ethereal, the 360 can, by smart application of gearing, do at least two out of three things well.
And hang on, once more; Lets say you choose an A518. The gears in hi-range are;
2.45-1.45-1.00-.69od.
But you have a 2:1 transfer case.
And lets use the 3.23s for this exercise. and lets drop down to 28" tires.
Ok 65= 1740, a bit easier to cam for.
Your low-range gears are ;2 times each of the gears in the main box, so
4.90-2.90-2.00-1.38
with the 3.23s, we get road gears of ( 3.23 times each of the above ratios);
15.83-9.37-6.46-4.47(in low-range)
If you notice;
4.47 is a good gear to trap the 360 in, making
90= 5320/ 93=5500/96mph=5660/99=5840;
all at 10% slip..........still in low range, but, with the A500 in od.
I think your truck might not make 99 but it might make 90, with the small cam I am thinking of.
To make this work, I am thinking of a solid lifter cam............ a short period, low-overlap, that makes peak vacuum at or near the cruse rpm already established at 1620rpm. And you will have to bump the cylinder pressure to the max for best power results. But at cruising, you want to be able to run cheap gas.
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more coming; I got some errands to run.
I'm back,lol
so at this point, lets recap;
I'm working with a 360/5.9M, and the overdrive Chrysler automatic known as the A500, with a 2-speed transfer case, and 3.23s. Tires would be 28s at the track, 28/30s otherwise, and 30/32s in the mud.
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now we need to build the engine.
Here are the parameters;
> cruises at 65=1740 with 3.23s and 28s in loc-up/ .69 overdrive.
> don't care about power, cuz we got rpm; will be trapping in 4.47gear
> don't care about torque cuz we got gears; 15.83/9.37/6.46; which will get us to 69mph@5000rpm
> aiming for efficiency at cruise rpm.
> must burn cheap gas, without detonation.

First I'll tell you what I would do, then change it up for budget.
as to the cam;
>I am aiming for best vacuum by 1740rpm; so reversion has to have stopped and all the air in the intake has got to be moving in the same direction.
>because I will be running; a modest stall, a wide 1-2 split, and offroading, I need a broad flat power curve; don't care about absolute power; and really care about just having fun. Right so far? So to help get the truck moving in hi-range, to help reduce the effects of the crappy 2.45 x3.23 starter gear, which is what sucks your average fuel economy into the basement, I'm gonna ask for a 2400 stall, to get the delivered footpounds up, so we can get up to speed in a reasonable period of time.
But, the engine still has to make enough power at 1740rpm to actually pull the truck at 65 mph. If it doesn't make enough power, then the roadspeed will keep on falling until you get sick of it and downshift into direct and claw my way back up to 65. And this power has to be made at a small-enough throttle opening so the mains don't get too involved. This is gonna be tough. I've done it on my 68 Barracuda so I know it can be done with a 3650 pound reasonably aerodynamic car. But with a flat-faced truck wearing 30s, hmmmm. IDK maybe 1740 is a lil low. For the moment, let's continue with the 3.23s, so I don't have to redo all the math. But if your truck already has 3.55s, Ima thinking that would be a better choice.
Ok so back on topic;
Ok so first thing is I need a spread-bore carb so that if/when it does get up on the mains, it won't drink all my gas away. Next is the cam. Since this rig is gonna trap in Second at 5000plus rpm with 3.23s, I need a cam that power peaks at say 4800, and that points to a cam in the 215 to 220 range, right on target. So lets look at those. I'll say a 218/226/112
In an FTH (Hydraulic Flat Tappet), you can add clearance rams of about 46 degrees so the advertised will be about 262/270/112, and that points to an Ica of 59* and that will get me around 167psi at 10/1 compression ratio. But-um, I'm gonna run alloy heads so I can pump this up to 185 psi, and so I get that at 10.7Scr at my 900ft elevation. As it happens, the 360 falls together at around 10.7, so this is a no-cost option with 63cc alloy heads. And I have run 180/185 on 87E10 since 1999,lol, so I know this works.
All that very high pressure at low rpm will make her a powerhouse. And I'm pretty sure that pressure will make enough power to cruise at 1740. I know that my Barracuda with a bigger cam, was able to cruise 85=2100/ 65=1600, at a very small throttle-opening..
So to recap what I would run;
> 360 cubes, 11/1Scr, 262/270/112 HFT cam, spreadbore carb on a small plenum modest runner size dual plane, headers yes, cuz this cam still has 42* of overlap, so the headers will help keep the beast moving after 4000rpm, and especially thru the 4800rpm power-peak.
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Now, you may be thinking that alloy heads are out of your reach. But consider what you don't have to spend of sacrifice;
> to run 87 gas with open-chamber iron heads, your pressure will have to top out at 150/155 else you will likely get into detonation. That is a 30% pressure reduction.
To get that power back at low rpm, you will need a cam size at least one or maybe two sizes smaller, or a higher stall, or a lower starter gear, or some combination of these.
To get that power back at high-rpm, you will need a cam at least one or maybe two sizes bigger. or a bigger engine.
Because these two needs are in opposite directions, there is NO satisfying both.
The gearing has already been set, so that leaves more stall/smaller cam. We don't want to go there.
Furthermore, as I said; with 63cc closed chamber heads and say KB107 flat-top pistons, the Scr comes in around 10.7 and the Q comes to .040 with .028 gaskets. Thus saving you the machining costs of; decking, head-milling, intake shaving, possibly porting, and setting up a tight quench. and the new alloy heads already should have a decent valve-job, and probably come with the right springs, and your stock pushrods will likely work. So that's a lot of offset money right there.
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for you now
but hang on; if your current 360 is not burning oil, has decent compression and oil pressure, there is nothing stopping you from leaving it in there. With a 2/1 T-case, in low-range, it will feel twice as big as it is,lol; and the small factory cam will make the best fuel-economy it can at the current cylinder pressure. Yes, with 3.23s it will be lazy off the line, but you can change that with stall. with a lock-up TC you can go sorta crazy on the stall. Every 200 rpm will bring a noticable difference in take-off performance, until you get into absurd-for-street stalls. I myself am partial to a 2800, but I can see a low-compression 360 wanting a lil more; But NOT a 5.9M.
So now we are opening the door to your 5.9Magnum, RAM transplant.
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now, I know that you are keen to make this a manual-trans truck, but honestly, your options, AFAIK, are too limited and not really conducive IMO, to what you want to do.
If it was me; I might build a custom console, install a manual shifter with a truck stick on it, and-um use my imagination,lol.
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once again, we haven't talked about altitude.
At 5000 ft, NONE of what I have talked about applies.
At 5000 ft you are pretty much limited to starting out with a bigger engine.
I have no idea if an A500/transfer case even exists..........
here is a 727/NP203

images?q=tbn:ANd9GcS9XSAIRuvsxk8hYeKzHujC5F7K9VVs5-_i3w&usqp=CAU.jpg
 
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Get a wife; she'll strangle all your truck dreams, ............


Hahah people keep recommending this idea but I keep disregarsding it :lol:

Now, for the altitude... its not like Im going to be living up there, or even go there more than once a month...I still have to attend work, and overwork...specially if I want to keep the wife idea away. So, its more like going to the beach, and the mountains hardly go over 4500ft altitude. This brings me to an important point I haven't addressed- Its VERY hard to get parts here, let alone complete engines/trannys. Everything I have I have imported from the states, or some stuff laying around from grandpa and pops, and here is a land of chevies, not many mopars around...so thats a big issue. I have very little availability on spare parts, so I have to make do with what I have or overpayfor imported parts. Also, gas here sucks big time, so thats another issue.
As for what I have...I do have a 360 .060 over, with ugly van compression (like 8:1) and ugly van heads (nicely ported). Hugues' Whiplash cam (I do have a comps XE268 laying around, I have a manual reverse 727, and 3.55. Radials, for now, nice 15´sx8. Msd ignition, a 750 eddy (have a 500cfm laying around, eddy rpm intake, hooker headers, powermaster starter, and a nice optima battery. This makes starting the engine an easy task, and we dont get too cold a weather here. It does rain like crazy.

I have a 318 block I could use, have a 383 (Im thinking of this, but I was planning to swap the slant off my dart63 for the 383, and a 727 push button). I could get a big block for the Dakota, and make it fit. But the 360 is a finer than fine engine, and i could always eventually stroke it, i guess. I found a NP203 but for a chevy, so i guess I have to get an adapter? Or buy one off ebay already mopar fit.
But the more inbfo and input Im getting, specially from you (I appreciate it a lot, btw, thanks for taking the time), Im thinking this might be a very difficult task, and It would probably sacrifice the well being of the car. As said, I could get a Ram, say a 99er, and hop that up, Or, crazy thought, 4x4 a VAN, or a Caravan, which is something that would do the job much better, for camping comfort.

So, I will study your engine build idea. I WAS thinking of hopin up SCR to 10.5 with some nice hypereutectic, use some nice J heads I have laying around, big valves, and change the whiplash for the comp XE. Keep the 727, make vroom vroom, go fast sometimes and "cruise" other times, go to mickeyD's or Taco bell with the DAKOTA, and find something else, a cheap old car thats already setup for off roading/camping, and be practical.

Practicality...thats a good idea and a good moral to this story, no? Thats also why the wife idea im not too fond of. :)

Thanks again for your help. What do you think?
 
Oh BOY! there it is 4500ft
that's the problem.
that's worth about 20/25psi right there.

Now, it's unclear to me from your post whether you will be operating your truck exclusively at 4500,
or whether you will be just taking occasional trip up to 4500, and normally operating at some lower elevation..
You cannot build a normally-aspirated carburated engine to do both. And you normally have to rejet at about every 2000 ft change in elevation, and every 30*F change in temperature.

At 4500 ft, to meet your stated goals, forget the cammed-up 340.You will need more stroke.
You can get a very-high compression 360 with aluminum heads, into the ballpark, with a small cam ; (a solid-lifter type recommended);
but because of the 20/25psi loss in cylinder pressure from sealevel to 4500, you will have to set it up for borderline operation at the lowest elevation that you plan to operate it at, using the best gas you have available, and then at 4500 you will need to rejet your carb probably twice on the way up or down, and you'll have to live with the powerloss at 4500.
Or you can take the easy way out and just install a bigger engine, set up for some in-between elevation, at a lower cylinder pressure, but you'll still have to rejet when ascending/descending.

Your last option is to just supercharge your current 360engine; could be a super or a turbo, either way, but you still have to address the fueling issue.

But if you are only migrating a thousand feet or so, then you can cover both ends with a high-pressure 360, and a modest solid-lifter cam.
 
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well at 1500 ft then;
my recommendation would be a minimum 360.
But again, you will have to build it for the lowest operating elevation, else, at the lower elevation, at WOT, it could detonate itself to death.
In lieu of EFI;
I would recommend a Double-Pumper for ease of jet changes.
___________________
I'm at 930ft exclusively,and 3650 pounds, and I run a 360, so I know that it is possible to make a 360 into a "powerhouse", and with gearing, to make a "torque-monster", and with the right combination of parts, mine has made better fuel-economy than any 318car I have ever had. The 360, IMO, is an extremely versatile platform.
But it cannot do all things best; generally pick two; you can make torque and economy, or torque and power, but forget highpower and economy.

And finally; if the factory iron open-chamber heads have to be used, that puts a bit of a limitation on what you can do, at 1500feet elevation, depending on your expectations..
What I mean is your total chamber volume before any machining, with those iron heads and KB107s, is about 88cc, making your Scr at .020 overbore to be
(744.6 +88)/88=9.46
So to get the pressure up to 160@1500ft elevation (about the max you can run on pumpgas) will require a cam with an ICA no greater than 53* ................ about what the 360 2bbl has on it.
As soon as you start closing the intake later, it starts dropping the pressure, and away goes the bottom-end torque. By an Ica of 64* like is on the 340 cam, the pressure is down to 145psi@1500ft.
Now; you can overcome this, to a degree, in low-range for off-roading. And in high range, you can get off the line with a high-stall TC.
But;
once you get to second gear in hi-range and past the stall-rpm; that's when the lack of pressure shows up, which is only made worse by a heavier vehicle.
But once you get up to where the power is, it's not so bad anymore. But getting there with hiway gears can take a really long time. And if, in addition, you have a performance cam in it, then the powerband will be even more focused on top-end power.

Here's my opinion on the A833od for this application. What happens if you spend a truckload of money making it work, and then you drive fifty miles and break that fragile 20tooth mainshaft gear? Which then takes out the cluster drive beside it? And now, not only are you walking, but also shopping for another Box.
IMO
a far better and more reliable idea is to use the 727.
I had a 92 Dakota 4x4 dual-range. With a column-shifted 727 and a floor stick. That worked really nice. Had that been an off-road truck, I would have installed a floor-shift for the auto, and had a blast. But for me it was just a winter utility truck.
Hyup, IIRC that was a 4-speed auto with a lock-up.
IMO, that would be ideal.
 
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While the 340 can be fun,
the 360 will have a whole big buncha more low-rpm grunt.
While at 3000 pounds the 340 would be more than up to it,
the 360 will be better at 4000.

400 meters is a very long way .
a 340 done up for that will NOT like the 3+1,A833.
Even the 360 at 4000 pounds will have trouble with that trans, with a cam of more than 223@.050
It's not the getting off the line that is the problem; rather, it's the 1.67 second gear that sucks.
With a 340;
Let's say you run 28" tires. And low gear is 3.09 so you want a starter of say 10 or 11 to 1. And that means you can run 3.55s. Which is a great starter gear; not too deep, and not too shallow, but perfect.
But with 3.55s, 65= 2000 rpm, so if fuel economy is on the table, this is borderline too low for the 230* cam your 340 is gonna want. With the 230 cam 3.91s is what she wants to cruise with. But 3.91s make a starter gear of 12.08, which means that the rpm is gonna climb very rapidly in first gear; annoyingly rapidly. And Bam! you will be in Second gear... typically shifting at say 3200/ 22mph(3.91s). But at 22 mph in Second the Rs drop to 1720rpm, so the 340 is way out of it's element, as in total lack of torque. But you say com'on, it's got 3.91s why is it so doggy?
Ok, the 340 with a 230* cam to satisfy your rapid transit to 400 meters, is gonna want to be up at around 3700 before she will deliver some power. In Second gear (1.67 x 3.91), this will be, wait for it..... 47 mph. So no matter at what rpm you outshift First, your 340 is gonna have to buzz up to ~4700 to find some scoot; and that's with 3.91s! To get 47 mph in First gear requires 6800 rpm. If you are running a 230*cam, it will peak around 5200 and you will shift it at around 5500, and 5500 with 3.91s is about 38 mph. On the 1-2 shift, the Rs will fall to 2980, again waaaay into the marshmallow zone. So now the 340 has to struggle up to 3700/47 mph. But 5500 in Second is 70mph. On the 2-3 shift at 70mph, the Rs will fall to......3300; let the struggle begin again. If your 340 equipped 88Dakota can hit 90 at 400M, that will be 4200, way down the power-curve.
So, like I said, Second gear is the problem. It's too far from first, and just as bad on the 2-3 shift. You can put Second Gear where ever you want with rear gearing, but that just messes everything else up.
Check this out. A good place for a streeter to be geared is 2800@32mph, in Second Gear. This is comfortable to cruise around on, and at the downshift into first, the truck will rocket forward.
With 3+1 box, this will require ~4.30 rear gear, and on the downshift, the Rs will jump from 2800 to 5200 right on peak power................... but you got only 300rpm to 34mph and then it's back into Second; that really sucks. Now;
With the Commando box, 2800@32 mph as before, will require a 3.80 gear, rounds to 3.73s, so 32 will be 2750, and on the downshift into First, the Rs will climb to 4420 (instead of 5200) and you can wind that up all the way to 5500@40mph, BadaBoom!
What about the 360?
Well the picture is a lil brighter. For the same 400Meter performance, you can run one size smaller cam. This will get you a double-whammy of more low-rpm power; Firstly the 360 has more by virtue of it's stroke, and secondly, the smaller cam can deliver more.
So now, maybe the torque comes in around 3400/43 mph.
But hang on, why are we still running 3.91s? The 223*cammed 360 does not need nor want them. 3.7s will do just fine. Even 3.55s.
So with 3.55s, 3400 will be , wait for it......48 mph. Chit with a capital-C.
I'm telling ya that 3+1 box is terrible for a hot SBM
I made that 3+1box work by running alloy heads and cranking the pressure to 185 psi. And it still sucked in my 367 with a 223@.050 cam, and worse with the 230@.050 cam.

My tip; Run the early Commando 4-speed and forget overdrive. It has the perfect Second Gear, and Third is right there beside it; and the 360 can easily pull the 3.09 gear with 3.55s. I'll bet the 340 will only be a lil softer on take off, running the same cam and same cylinder pressure.
Ok, now 3400rpm with the Commando, in Second gear, with 3.55s, is 41mph..... but, first gear will get you to 44mph at 5800, so BadaBOOM! The 1-2 shift at 3200(First), now gets you 24mph at 1990rpm, going into Second, that's 2mph faster and 270more rpm with 3.55s now, versus 3.91s with the 3+1 !! that's a mighty big win.

Here are the A833ratios, (with the 1 x23 input);
3.09-1.67-1.00-.73od ( 3+1 misery)
3.09-1.92-1.40-1.00 (Commando)
2.66-1.92-1.40-1.00 (standard box)
2.47-1.77-1.34-1.00 (the close-ratio T/A box.)
Now, plug in some rear gears, into this formula, and see what it takes to make you happy;

MPH= (RPM x TC)/( 1056 xR1 x R2)

Where TC is Tire Circumference which is; diameter x 3.1416
R1 is trans ratio
R2 is rear gear ratio
1056 is a constant that converts the resulting product into a simple speed number.

>Which engine you chose depends on how low a rear gear you are willing to run, how much tire-spinning you want to do, and how much you value low-rpm running on the hiway. As for the 400meters, either engine will get you there,in the same ballpark, depending on how you set it up.
>The 4X4 will suck some power too, so another reason to go 360.
>IDK what your gas quality is like in Costa Rica, nor at what altitude you are running, so that, if you cannot run high-pressure, points to the 360 again.
>Alloy heads will let you run 87E10 to at least 185psi in my experience, with full-timing.
__________________ opinion coming_____________
Don't buy into the 340 better than 360 hype; that is just not true. Combo for combo, the 360 will do anything a 340 can, but with more low-end grunt.
I bored mine out to 4.04 so now its same as a 340 except has a longer stroke. And I cranked the Scr up to 11/1, better than any factory 340 ever was; and no factory 340 ever pumped 185 psi. So my 367 is like a 340 on steroids, just what you Dakota needs.
185psi with a 223* cam is a flippin' tractor at low rpm, a powerhouse thru the midrange, and I set mine up to rev to 7200... jus cuz I like to hear it screaming.
My rig is 3650 with me in it, and she likes 3.55s, but likes 3.23s almost as much.

BTW;
that overdrive is "fragile" to say the least. I blew two of them up, just by accidentally slamming the trans into "fourth" which is easy to do with certain bigger number rear gears. And when it shatters it goes everywhere, including down between other gears and wipes the whole trans out.

Ok time to cut it short,lol

Oh geez. That just took all the fun out of this project.
 
Oh geez. That just took all the fun out of this project.

I was actually remembering some of your advises on previous posts I made, and thought to myself: "I should just do it, have fun, break ****, and start over"

Its not like I don´t like spending time with and fixing the car anyway.
 
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