'71 Duster 440 or 360? Pros and cons

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70aarcuda said:
just remember you are going to need a 727 for a big block ...

I would stroke the 360.....big inch small block..still have a light engine package along with the current 904.
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x2 so would i. and i love 440s
 
Check out my site if you want an idea of what you're getting into. I love the stump-pulling torque of big blocks and would do it again and again. Yes, you'll spend more money doing the conversion. Yes, you'll spend a little more on gas. I don't road race, don't care to, and think it handles just fine (I have heavy torsion and sway bars). Whether the swap is worthwhile is in the eye of the beholder.

As mentioned that WP housing appeared on '73 and up BB's. A simple flat top piston swap would bump compression up to 9.5:1 with those heads, if desired.
 
Hmmm. I already have a "fun" street car. It's a '74 Nova with a 350. It gets 17 mpg and is a blast to drive. I am also in the process of building a '65 Mustang with a '95 5.0/5 speed. That car is getting painted right now. There really is no rush to get this Duster thrown together. I am just fine with taking my time on putting it together. The 440 looks brand new inside. It has flat-top pistons already. The problem is that they are way down in the hole. I have never seen pistons so far down in the hole as a matter of fact. The heads already have double valve springs. I guess I was thinking about building a 440 car just because I have never had a BB car before. The thing is I realize that there is a ton of potential in that 360 if I build it right. My fear is if I go ahead with the 440 build I may regret it and wish I had went with the 360. I'm not rich so $ is definitely an issue. Especially with the Mustang I am already building for my girlfriend...... I appreciate all the responses. Pretty much seems like most feel that a small block build makes more sense.....
 
Actually given what you just said, I would recommend even stronger that you do the big block. I don't know your age, but my wife and I bought a 68 GTS convertible in 1983 (I was 23 at the time) with a 340. Neat car and plenty fast enough in stock form, BUT I always wanted to build a big block a-body and that was the WRONG car to do it to (one of 271 340/auto 68 GTS convertibles sold in the US).

So, in 1988 I picked up a 67 Dart GT hardtop. I put a stock 350hp/440 in it with a four speed, 3.23SG 8-3/4 rear. I never finished the cosmetics because it was such a blast to drive (I also built the suspension to handle reasonably well). Then my older son turned 16 and needed a car to drive. That was his daily driver for a year and a half...The car is long gone, but he AND the parts survived to be put into my other son's 67 Dart GT convertible and now I'm building myself a 67 Barracuda convertible that will get a 440/auto.

I really doubt that the 360 will be enough different than your Nova (although being a Mopar WILL handle better) to feel like it was worth it.
 
Jim, I am 25. That is a pretty good point you bring up. I would like something that is very different to drive than the Nova I already have. I love that car for what it is. It most definitely is a really great driver and there is a lot done to the 350 that's in it. I think I could live with this Duster being less than cosmetically perfect. I think I am going for a cruiser with some serious power and bragging rights.... I REALLY wish 4 speeds were easier to find. The aftermarket options are extremely expensive.
 
bOb shingler said:
it's going to cost a ton of money to rebuild the 440 adn 727 and get it installed. first let me say this, there is no better hotrod than a bigblockdart, period. this being your first time attempting to install a rb into an a-body it's going to be a patience trying ordeal. please take note of the amount of hair you have before you try it because you will have less afterwards.
this is what i'd recomend, set the 440 and 727 over in the corner and rebuild the 360 and start driving it. we're talking fun here. after that is taking place rebuild the 440 and 727 to pretty good horse power that you want. start collecting all the other parts you're going to need to get it installed. find a rolling a-body drag car and put it into it and then start having some eyeball popping fun at the drag strip.
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I agree regarding using the 360 first, and don't put much into it. Stock rebuild with a slightly hotter cam, like the 340 automatic grind or similar. Keep it mild and drivable.

About buying another car to do only drag racing...only if you have tons of room to store everything securely, and the spare money and free time to focus on two cars. And a truck and trailer to haul the car to the strip. Otherwise build the 440/727 combo for a swap in the future. 440 A-body on the street is a lot of fun, and damn quick.
 
Pull the pan, check tolerances on the bottom end, and check for bore wear, then seal it up real quick, low buck as possible on the 440 and run that b*tch then.
 
bridger5228 said:
Jim, I am 25. That is a pretty good point you bring up. I would like something that is very different to drive than the Nova I already have. I love that car for what it is. It most definitely is a really great driver and there is a lot done to the 350 that's in it. I think I could live with this Duster being less than cosmetically perfect. I think I am going for a cruiser with some serious power and bragging rights.... I REALLY wish 4 speeds were easier to find. The aftermarket options are extremely expensive.
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I had guessed that you were younger. Shop around for four speed stuff. Take your time. I got lucky when I collected the four speed stuff that is in my son's car. You've got plenty of time (then again I told myself that when I was your age and all of a sudden I'm 53....)...
 
You know if you said you already have a few small block cars, we'd have suggested doing the big block. A 360 in a Duster is the same thing as a 350 in a Nova. Why do what you have already done?! Just be aware its expensive finding all the rinky dink pieces to swap out a SB with a BB, just plan on spending an extra grand and you'll be safe. I'll suggest you make sure you have at least 10 to 1 compression one way or the other. I did a mustang with a 390 that ran 11:1 compression between the pistons and milling the heads. It was a finicky motor that always ran hot.

BTW I got your bragging rights, right here :) http://www.forabodiesonly.com/mopar/vbpicgallery.php?do=view&g=7271


Yeah I'm voting for drive the 360, until you have all the parts for the conversion then swap over. And get a big big radiator.
 
Don't swap to the 440 till you've been able to make it worthwhile. As it is now, it's probably an 8.2:1 comp motor, and won't run all that great unless you cut the heads and do a lot of tweaking.

Start buying good pieces for the engine and drive line rebuild, find a good shop that knows Mopar, and start getting the chassis ready to handle the swap...all while you drive it with the 360.

and don't go crazy with the engine build - you can go pretty damn quick with a mild 440. The car in my avatar had a 9:1 standard bore 440, .474 hyd cam, msd 6al, Holley street dominator intake, stock 4779 Holley, 2" CPPA headers, stock hi-stall converter, 3.91 sg rear. Best it ran was (corrected for sea level) 11.69 @ 116.86 on pump 92 octane. Not my quickest car, but was actually the most fun, because I could drive that thing anywhere, anytime (and I did).
 
if you want to cut a turn go small block ..but the 440 will give you a whole different ride/torque feel ....surprising to hear that a 360 will run with the 440 ..hasn't been my experience ..getting the power to the ground takes a little trial and error but can be done ...if possible ride in both IF you can find 2 a-bodies and see if there similar ..think you'll see a difference ..cost wise goes to the 360 as the 440 has extras ( 727 ) right of the bat but I don't think they out weigh the benefits ..course I'm a little prejudiced but I've had both engines in my dart with a 4 speed and I'm sure I'd do it again
 
Theres no replacement for displacement! Seriously, ANY big block car is going to be a blast! I'm from Oz, and am currently building a 400/470 stroker big block for a VF Valiant hardtop (I think 68/68Dart coupe in the U.S?). We are in the same boat in that this will be my first big block car. Of course, there will be weight differences etc etc, but are easily overcome with aftermarket bits (ally heads and manifolds for example).

I was going down the path of a 360/408 stroker, but every man and his dog seems to run them, and I like the idea of not needing to rev the nuts off my BB to make power. IMO, less revs means less strain on you motor, and I'm not really in a position to be under the bonnet after every run.

Most of all, its nice to be able to pull up at a club meet, or car show, and know that I've got something a bit different to most of the other guys. I'm not a racer, I'll run it once just for a timeslip, but mostly it will be a weekend warrior with enough stick in it to embarrass a few small block Chevs and Fords we have in our area! It really comes down to preference; Either build will impress you if you do it right, but if I already had a stout small block equipped car in the shed, I know what I'd be building!
 
In my humble opinion you should go with the small block. The money you would spend on headers, engine mounts, k-member mod's, a 727 trans/torque converter, driveshaft modifications, big block radiator/hoses, fan shroud, bigger battery, torsion bar upgrade, and the time you'll have chasing down the correct parts just wont payoff in the end, unless you just want the bragging rights that go with having an A Body with a big block. Hey, there was a reason for Dodge/Chrysler/Plymouth to put a B/RB Engine into an A Body but they had an unlimited budget.
That said, I'm not far away from finishing my '67 Dart GT with a 383/727 which was originally a 273 car. I love the sound of a Big Block Engine. I have 235/60/14's on the rear with a 3.55:1 Sure Grip, Traction Bars/Pinion Snubber that I'll just dig wicking it up and smokin' the tires as far as I want to.
The moral of the story: Its the swap from a LA to B/RB that makes it expensive. If your on a budget stick with the small block, it will definitely put a smile on your face at a much cheaper price.
 
There's no replacement for....well,how many times have you heard that before.If it were me,I'd do it.The 440 is going to be so much more fun on the highway and driving around town.I love that big block torque when you're cruising down the highway and you "test out" the passing gear.The biggest concern is the clearance issues on oil pan,exhaust,etc..I have a 71 Demon that I'm going to pro street,back half,4 link,blah,blah,blah.I plan on putting a stroker B motor in it though.Look at it this way,if you don't like the 440 then you can always put the 360 back in it.At least try it out.
 
If you could save every dime of advice you'd pay for the build. Here's my 10 cents worth. "You can't lose either way..."

I think most possible pro/con points have been made but I can think of one I haven't seen. A very real value of doing a small block besides the weight advantage is the easy ability to economically stroke them to big block displacement. I sure wish that option had been simple and cheap when I was most interested in killer performance 30 yrs ago.

What hasn't been pointed out is the same is now true of big blocks. For two grand in parts that 440 can be a 512 with the added benefit of such light bobweights it'll snap rev like a small block. Add another grand or two for aluminum high flow heads and you've got streetable torque and horsepower that only a full race or blown small block could touch.

If I was still aspiring to king of the street that's what I'd do :burnout:
 
a 400 stroked to a 500 with aluminum heads and intake will weigh less than a stock small block with iron heads... a 440 block is about 25 pounds more than the 400

so what is the problem with "cutting a turn" with big blocks?
 
I have done the 440 swap into a 74 Duster. Put aluminum heads on it with a good aluminum intake to lighten it up should weigh about the same as and castiron smallblock. The only problem with the bigblock swaps is the cooling system try to not run a high volume water pump it moves water to fast.
 
I've built 12 big block A-body's over the years.

As far as having to have custom drive shafts that's not quit correct.
A drive shaft that came out of a car that had a 727 in it stock will work.
The only thing you have to worry about is whether it had a 8 1/4 or 8 3/4 in it as they will only work with that rearend.

Low comp engines can be made to run low 12's.
Here's the combo with the pistons down the hole .160 and 8 1/4 rear end with 3.91 gears.

Stock 78 440.
Mopar .528 solid cam.
906 Heads,just cleaned up.
Performer RPM intake.
Holley 780 vaccum secondary carb.
Schumacher headers.
Stock ignition.
Aftermarket Coil.
Very well built transmission.
3500 converter.

Ran 12.21 all motor.
100 hp juice 11.59
Changed out the heads to stock stage 6 ran 11.87.

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Trainee Jon.
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This car has Atco front and rear sway bars,change the tires and now you have a carver.
Car weighs 3200 lbs w/out driver.
Total investment in this car not counting the cost of the Stage 6 and the trans as the trans is a back up for the 10 sec pump gas 67 Dart.
$8000

I did take the engine out of the 67 and put it in the Duster and ran a 11.05 et.

I do love the BigBlock A-body's.

Pump gas 440 Street car-10.71 et
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9.08
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Whether you build a big block or small block car,just have fun doing it.

Side note,when we go auto-crossing my wife's 4 banger beats all of my big-block car's.

2005 SRT-4 ACR.
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So if you want A corner carver?
Big-block,small-block or 4 banger.
Again,just have fun.
 
One you need to deside on what you want.(BIG BLOCK OR SMALL BLOCK).Second you need to talk to people that had both cars with both engines.Most people that have a A body small block never had a ride in a big block a body.It is two different animals.Stroker small blocks and a big blocks are still different animals.If you want a big block in your car I say put it in.You wont go back to a small block again.Get numbers on weight and then build the car and weight it.You will be surprised how lite A body's are with big blocks in them and be surprised how they handle. I have owned them all and I never had a small block have the power of the big block.In a A body a big block is just assume. If you want a big block I say put it in ,If you want a small block then put it in.It's all on what oyu want. Mark
 
Be prepared to spend close to $1000 for a set of headers on the 440 unless you want fender well exits which will really restrict what you can run on front tires
 
BB advantages - you can say , I have a 440 Big Block, more torque
SB advantages - can go just as good or better, lighter, more room in the engine bay for better extractors etc
I have a 383 BB & wish it was a 340/360. Only good point as far as I'm concerned is the fact I can say "It's got a Big Block" - Big Deal!
 
A set of Schumacher's are about $700 coated.
I've had these headers go 11.59 et.
 
Just skimmed thru a lot of the posts but noticed the mentioning of the desire of a 4 speed. As was mentioned just be patient and keep your eyes open, you will be surprised what you will find. I recently sold a 4 speed and some clutch parts for what both the buyer and I thought was reasonable on both ends. I think I sold Tom a 4 speed, and most of the clutch parts, pedal assembly included for 250-300. I have a buddy that owns a trans shop that every now & then has a customer come in with an old car that has a stick in it and they drive away with an auto......for various reasons. My buddy knows very well what these transmissions are worth but really does not care, he is not in the business of selling parts.....so he normally lets stuff go for what he would get at a scrap yard. If you would like I will call him and tell him to be on the look out for an 833.
 
It took me less than a second to decide on putting a 440 in my 6-cylinder 71 Demon. And a 400/470 has been in the works. I am old school and still have the need to get greasy and want some nasty revving, throaty sounding sleeper to cruise the boulevard. I walk by a lot of 318 V-8 Darts and Duster. Isn't it always the RB that catch your eye? Unless it has big turbos. Everyone has different ideas of daily driver's and fun. Do you want an adrenalin rush or are just getting some milk? I prefer the milk shake...
And I found a pair of used TTI 1 7/8 ceramic coated headers for $600. Mine will never be a show car... but will definitely turn heads and give me smiles for miles. Do you want Burger King or a juicy steak? Easy is not always better. Michelangelo didn't paint the Sistine Chapel in a day and he would have thought that a painting a barn would have been worth it either. lol
Not saying a stroked 360 wouldn't be fun. But if your putting all that $$$ into a small block. Why not build a mild manner 440 then. Just my 1 1/2 cents... inflation. Eazy is is not in my MOPAR vocabulary. You want eazy... buy and Chevy. No disrespect.. I like the Novas style. MOPAR to me is a little madness and desire. But then they will never confuse me with being normal. MOPAR RULES!!! :)
Back in the day... when I was young... every thing was like a loaded gun.
So are a .22 cal assassin... or do you feel lucky???? PUNK!!! lol
:burnout:
:burnout:
 
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