Ok , need to step back

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zigs

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I picked up a 70 Duster last year as another project thinking I needed another car. A year
later Im finding out that may not be so and something has to go. The Duster would be a fun build and I have done alot so far like replacing left rear quarter and installing
GTS pulges on the hood plus all the cleaning and sanding but there still alot, ALOT! of time work and money. The Dart is finished but has a 470 really not MPG friendly and I would like to be able to cruise away from home and the fact I have some seperation issues with the Dart. Sorry this is so long I need to sort it out. Heres what Im thinking. I have a built
340 for the Duster. Im thinking of pulling the
470 and swapping in the 340. Sell the 470 and Duster use that noney to upgrade Dart .
Thoughts?
 
I wouldn't worry about the gas mileage, how much worse can the 470 be?

Say you drive a lot and put 5000 miles a summer on. and the 340 gets 15 mpg and the 470 is terrible and gets 7.5 mpg and not sure what your gas price but say it's $2.50, 340 cost $833 a year 470 $1,666 a year, That's if you put on that many miles on and the 470 gets half, which it should be better than that unless it's poorly setup or really radical, and the cost of the swap probable eat up a year or two savings anyways. I find when doing more then a good tune it's cheaper to put the money in the tank then trying to gain mileage from upgrades usually not cost effective.
 
Put a mild cam in the 340 and enjoy it as a cruiser.
Even if it isn’t a OE 340 car, it will command some bucks. Use the KISS method and it’ll be fine. Even if it is sporting a bunch of OE stuff like an intake and carb, it will be a cool driver.

Keep the Dart to stomp *** and use the Duster to cruise.
 
Milage isn't just about the costs. It's also about the distances between fuel stops.
 
Put a mild cam in the 340 and enjoy it as a cruiser.
Even if it isn’t a OE 340 car, it will command some bucks. Use the KISS method and it’ll be fine. Even if it is sporting a bunch of OE stuff like an intake and carb, it will be a cool driver.

Keep the Dart to stomp *** and use the Duster to cruise.

..........Or put a mild cam in the 470 and enjoy IT as a cruiser.........
 
What IS a 470, B or RB?
B block 400 w/a 3.90 stroker crank.
(That’s IIRC...)
Scroll down on this page;
Stroker Kits-440 Source

400 >> 470. (3.915" stroke/6.535" rod) Approximate Bobweight: 2160

This kit is a great choice for an engine that will see a lot of street use, but still make some serious power. The low deck, 3.915" stroke
 
I sat down and figured out last night what it would cost to finish Duster. It would be roughly $17000. The engine swap on the Dart would be around $5000 . The 340 is already built and going to be in the 400 HP area. I like the idea of going back to small block. In the 13 years Ive had the Dart Ive only had it on the street about two years working on or changing something. When I retired Ithought needed something more to do ,thats where the Duster came in.
 
Put a mild cam in the 340 and enjoy it as a cruiser.
Even if it isn’t a OE 340 car, it will command some bucks. Use the KISS method and it’ll be fine. Even if it is sporting a bunch of OE stuff
Keep the Dart to stomp *** and use the Duster to cruise.
That was my first intension when I picked up the Duster but I also have room issues . Not having a shop only a three bay garage space is tight ,it makes it hard to work. I think I need to be senceable. I know I can get more then what I paid for the Duster and its all there including new parts
 
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if it ain't broke....... that Dart sounds like a badass car and there's a cool factor with that bored and stroked 400... you know what to do, cut your losses and put the Duster up for sale with the 340, chalk it up to an experiment you shouldn't have attempted.. recoup some bucks and move on. ...or you can spend another year working on it. :BangHead: JMHO.
 
It's a sickness many of us have. I'm retired also. Pretty close to being done on my '70 Challenger. I'm thinking maybe buy another car. But, then I say stupid I really don't have space to do the work. Then how everything adds up. I feel your pain. I think I'll stay with one. And not open up a keg of worms. lol...
 
if it ain't broke....... that Dart sounds like a badass car and there's a cool factor with that bored and stroked 400... you know what to do, cut your losses and put the Duster up for sale with the 340, chalk it up to an experiment you shouldn't have attempted.. recoup some bucks and move on. ...or you can spend another year working on it. :BangHead: JMHO.

Hell He USED to have an early hemi in the thing!!

Richard, I'm not sure a 400hp SB is gonna be much of a mileage / cruiser improvement over a mild 400 stroker!!!
 
if it ain't broke....... that Dart sounds like a badass car and there's a cool factor with that bored and stroked 400... you know what to do, cut your losses and put the Duster up for sale with the 340, chalk it up to an experiment you shouldn't have attempted.. recoup some bucks and move on. ...or you can spend another year working on it. :BangHead: JMHO.
Thats my thoughts
 
Hell He USED to have an early hemi in the thing!!

Richard, I'm not sure a 400hp SB is gonna be much of a mileage / cruiser improvement over a mild 400 stroker!!!
Thats my point Dell 354 to 470 Ive replaced rear ends. Im like a little kid in a candy store
another project isnt going to help. Look in your own back yards . How many of you have projects that are on the back burner. Your waiting for time,money,health, kids to move out. Two cars in my garage ,one will be favored more while one sets.
Dell 400HP VS 500 + their would be a difference and I think more user friendly.
I guess my point is . when I was young I needed thinks and could justify it. Now that Im older I dont really need thing. I have plenty to keep me buisy . Kids ,grandkids
Part time job etc. Its time to come to grips
 
Hell He USED to have an early hemi in the thing!!

Richard, I'm not sure a 400hp SB is gonna be much of a mileage / cruiser improvement over a mild 400 stroker!!!
Depends on the cam and state of tune. Intake, cylinder head and exhaust also play a big role in the area of efficiency. A small cam can make 400hp and still get good mileage.
 
Thats my point Dell 354 to 470 Ive replaced rear ends. Im like a little kid in a candy store
another project isnt going to help. Look in your own back yards . How many of you have projects that are on the back burner. Your waiting for time,money,health, kids to move out. Two cars in my garage ,one will be favored more while one sets.
Dell 400HP VS 500 + their would be a difference and I think more user friendly.
I guess my point is . when I was young I needed thinks and could justify it. Now that Im older I dont really need thing. I have plenty to keep me buisy . Kids ,grandkids
Part time job etc. Its time to come to grips

A detuned 470 will be more streetable than a hot 340, 1 hp per cid is kind of the dividing line depending on ones idea of what driveablity is. The 470 can always be made to 130hp more than the 340 at the same streetablity. A certain amount of performance is gonna have a similar fuel mileage. Less you start taking turbos. I wouldn't overly let mpg decided your decision can take decades to recoup money spent to gain mpg, now if you taking driveablity / performance with an eye to decent fuel mileage then that's a different story cause your not expecting to get a monetary return on your investment other than fun.
But it's up to you what you want.
 
I would sell the Duster and the 340 together as a package.
Keep the Dart as is or detune it slightly.
Gas mileage isn't a concern to me if you aren't driving distances of over 200 miles at a time.
Once you've had a big block in an A-Body, it's hard to turn back.
The torque alone will steal your heart.............
 
It's a sickness many of us have. I'm retired also. Pretty close to being done on my '70 Challenger. I'm thinking maybe buy another car. But, then I say stupid I really don't have space to do the work. Then how everything adds up. I feel your pain. I think I'll stay with one. And not open up a keg of worms. lol...
And thats where Im at.
 
I would sell the Duster and the 340 together as a package.
Keep the Dart as is or detune it slightly.
Gas mileage isn't a concern to me if you aren't driving distances of over 200 miles at a time.
Once you've had a big block in an A-Body, it's hard to turn back.
The torque alone will steal your heart.............
I like the idea of the 340 and as far as missing the torque, my 354 had probably more butt grabbing torque then the 470. The 340 should be very streetable.
 
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I like the idea of the 340 and as far as missing the torque, my 354 had probably more butt grabbing torque then the 470. The 340 should be very streatable.

Sounds like you know what you want :)
 
I sold my cuda with a 500 stroker and bought a Charger with a stock big block for the same reasons. I have to say I am really enjoying cruising in this car. I may get the urge to go faster, I have that reputation, but for now I am happy with the change.
 
if it ain't broke....... that Dart sounds like a badass car and there's a cool factor with that bored and stroked 400... you know what to do, cut your losses and put the Duster up for sale with the 340, chalk it up to an experiment you shouldn't have attempted.. recoup some bucks and move on. ...or you can spend another year working on it. :BangHead: JMHO.

Sometimes it's okay to walk away from something. No harm, no foul. One bad hotrod may fill your soul anyhow..... Everyone has their own idea about this but for me more than one of anything like this in my life is more than a plenty....

JW
 
Sounds like you know what you want :)
Pretty much. Bad thing is your hind sight is always better. Another thing I was thinking also is two cars in my case finished and unfinished , if something were to happen to me , my wife and family would have to deal with it and no one really knows anything about them about them. more then likely I'm going to have a 70 Duster and 470 with tranny for sale in the future.
 
Pretty much. Bad thing is your hind sight is always better. Another thing I was thinking also is two cars in my case finished and unfinished , if something were to happen to me , my wife and family would have to deal with it and no one really knows anything about them about them. more then likely I'm going to have a 70 Duster and 470 with tranny for sale in the future.


Yep...go with your gut.
 
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