3.9 Magnum in dart

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73_Dart

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Hello, I was wondering if any of you have put a 3.9 magnum v6 into your dart?
I have been thinking about doing this in my car, but wanted to see if anyone else has done it.
I have the v6 and transmission set up so I might be able to buy it. I know I would rather have a v8, but the v6 is cheaper right now. I also know that If i have a v8 I will get into more trouble than with a v6.
I have a 73 dart swinger slant 6 that it will be going into. I just want a little more power than the slant has.
Please dont just say do a v8 cause I cant do it right now. The v6 is more practical right now for me.
So anyone done this?
 
Not sure you would be gaining much if any power. I think it would be a pretty easy swap. That engine is basically a la with two cylinders removed.
 
FABO member dart64gt swapped a magnum v6 into a Dart wagon...you might shoot him a p.m. Sadly his wagon was stolen and trashed not long ago. But I bet he would give you some valuable imput.
 
SleeperScamp said:
Not sure you would be gaining much if any power. I think it would be a pretty easy swap. That engine is basically a la with two cylinders removed.
Click to expand...

True but there is little to no parts that switch over between the la and 6 mag but anyways with the time and effort I would think it would take to get that whole thing to work you would be done and in with a 318 V8 in half the time and be much more happier just my .02 :salute:
 
Yea or if you want small just put a 273 in 'er
 
He did say it was not practical for him, so why suggest it?
 
V6 Mag requires home made motor mounts. A500 requires extensive tunnel and crossmember work. Exhaust choices are limited.
John
 
Im wanting to find a cheap 2 barrel super six setup if I keep the slant for right now. I think I would get a little better mileage out of it than the one barrel (only getting 7 mpg) Right when i find a good deal on a set up, I have no money and cant get it.
 
Um 7mpg? The slant in my dart gets 20-23... Either this thing is running like crap or you need to put an egg between your foot and the gas pedal...
 
73_Dart said:
Im wanting to find a cheap 2 barrel super six setup if I keep the slant for right now. I think I would get a little better mileage out of it than the one barrel (only getting 7 mpg) Right when i find a good deal on a set up, I have no money and cant get it.
Click to expand...

If you are only getting 7 mpg now, even if it's all city driving, you may have other issues with the engine, unless the current carb is really screwed up or you can't keep your foot out of it!
 
I dont put my foot into it. I did a few times when i got it and it doesnt take off fast. so I dont do it any more. I dont know what the problem is.
 
You've got a lot of things to fix if you're only getting 7mpg. Odds are good you've got a Holley 1920 carburetor and that the brass ring holding the power valve check ball has fallen out, dumping tons of gas into the engine all the time and spoiling your mileage. Car will be really easy to start from cold if this is the case. Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download. Tune-up parts and technique suggestions in this thread. The slant-6s made before 1981 require periodic valve adjustment. You will want to get the three books described in this thread as quickly as possible, as your first tool purchase.
 
I drive it everyday. It starts up real easy, But then it will stall on me (if i dont keep my food on the gas some). Then it starts right back up after it stalls. Sometimes its stalls again to.
Dont know about this either.
 
If the carb is dumping a lot of fuel in to begin with, it may be needing the carb open to simply let more air in, which could help keep it from flooding out and stalling.

Really bad news is that if this has been going on for a while, then the gas could be washing the oil off of the cylinder walls and dilluting the oil. The engine could be suffering from a lot of wear also.
 
I noticed my oil was a little different color. It is also more runny. Its fairly new oil. just did it and filter and stuff right after christmas.
 
If your wanting to do this on a 73 dart (hense your signature name) I think you have to change to the v8 k frame or buy/make engine mounts to fit your K frame as the /6 K frame is very unique and has one mount higher then the other (v6 doesn't).
Then you have to adapt the fuel injection and computer from a donor vehicle to get the magnum v6 up and running (unless you buy one of those expensive 4 bbl intakes), you would be wiser having the /6 looked at if a v8 isn't an option and this is you only car. a v6 isn't a one weekend project IMO
 
I believe 3.9 F.I. Magnum can be converted just like the 318 F.I. Magnum for use in older cars. But, as mentioned, it isn't to easy or cheap. 3.9 intakes for a carb are not common and not sure how the distributor set-up would work.
I also don't recall if a 3.9 has the motor mount "ears" like thr LA engines or just has the flat pad.
 
Well the deal with the v6 magnum fell through.
So staying with the slant for right now. Now to figure out whats wrong with it.
 
73_Dart said:
Well the deal with the v6 magnum fell through.
So staying with the slant for right now. Now to figure out whats wrong with it.
Click to expand...
Probably a good thing. Fix the slant, it's a whole lot easier than swapping an engine, especially a swap that's not factory parts. Never a good idea to do a project just because the part(s), or engine, in this case, is available. Buying the 3.9 is easy, getting it installed is hard.
Even if your slant is shot, they're a dime a dozen.
 

Im not saying that my motor was bad. I just want something different. The magnum would be a little peppier and that i Know of not many people have put one in there dart.
 
An inline ( or , in the case of the 170 / 198 / 225 series , a slanted arrangement ) motor has a much better torque-range and output than a "V" motor .

7 MPG is freakin' horrible !!!

a 1973 motor ( Slant Six , small block or big block , excepting the 340 ) will have an EGR setup as well ( the 340 has EGR , but it's not
external ). If this system is clogged / leaking ( vacuum ) or just malfunctioning , your car will run like **** .

How's the EEC canister ? Does it have vacuum leaks ?
Is the PCV valve old ?
Breather clogged ?

You'll regret swapping the Slant out . It's a far superior motor to the 3.9 ( 239 c.i.d. ) .
Mopar Performance ( et al. ) used to make a 3.9 crate motor . I'm sure it's been long discontinued ( can't imagine why ... ) .
 
LH23H2R said:
7 MPG is freakin' horrible !!!

a 1973 motor ( Slant Six , small block or big block , excepting the 340 ) will have an EGR setup as well ( the 340 has EGR , but it's not
external ). If this system is clogged / leaking ( vacuum ) or just malfunctioning , your car will run like **** .

How's the EEC canister ? Does it have vacuum leaks ?
Is the PCV valve old ?
Breather clogged ?
Click to expand...

I dont know where the EEC canister is? Im not sure if i have vacuum leaks.
I dont know anything about the pcv valve
I dont know anything about the breather
 
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