383 vs 440

[Racingsnake]

I've got a '68 Fury wagon that I’m going to swap a 383 or 440 into. Not looking for a race car so a 383 would probably be enough power but it seems to be easier to find a 440. How much difference in fuel consumption is there between a 383 and 440? I’d like to get somewhere near 15 mpg at a 70 mph cruise with a 727, 3.23 gears and 235/70x15 tires. Is this a reasonable aim with either engine?

 

[detmatt]

Maybe with fuel injection. I bet the fact that the 440 won’t be working as hard to move a 2.5 ton wagon that there might not be a significant difference in fuel consumption between it and the 383. You might have a better chance at it with a 2.94 gear set and could probably even nail it with a 2.76.

 

[CBODY67]

As I remember reading, the 383 2bbl was allegedly a favorite engine of many Chrysler execs. The 383 will a bit less off-idle torque, but the shorter stroke like, personally. With the 3.23 and your tire size, it should run about 25mph/1000rpm on the highway. Going to a 2.76 will make it more like 28mph/1000rpm. With a somewhat "normal" cam, figure on about a 2800-3000rpm torque peak, which would be about 75mph with the 3.23s.

That "favoriteness" might have been related to a 383 2bbl being a bit more saleable to the general public, I suspect. Bigger than a 318 and not as thirsty as a 440, where the 440 4bbl was not standard.

Look at all of the things you'll need to alter with a B/RB where a LA currently is. A stroker 408 LA might be a better alternative. Not as much visual "pop" when the hood is openned, but MUCH easier to change spark lugs on.

Back to the orig question, I'd go for a slightly-enhanced 383 with AVS2 myself. Even if it might mean using a factory stock cam, a "Road Runner" torque converter, a good dual exhaust system with good headers or HP manifolds (if possible), and a modern fuel and ignition system. Keep it simple for best results, to me.

Just some thoughts,
CBODY67

 

[rapidtrans]

The reason a 383 2bbl was a favorite, at least in Dad’s case, was it ran great on regular gas. In fact we pulled that travel trailer all over the country running on Gulftane. Probably the lowest octane, and cheapest, gas available at the time yet that 383 never pinged climbing the Sierras or overheated running across the desert. They were also a sleeper in a B body.
I certainly wouldn’t go looking for a 2bbl specifically as a replacement engine upgrade today.
The 4bbl sounds too cool in the Monaco when I open up the secondaries!

 

[Luke Pokrajac]

My dad had a 440 in his 67 Monaco Wagon and it truly was a gas hog. He loved the car but always, always complained about the gas mileage...and it took premium gas. He even asked one of his mechanic friends if changing out the carb would help improve mileage. I have a 383 in my sport fury and it runs just awesome with a Lunati 256 cam in it...more power than you would ever need. And it's pretty good on gas with a 650 AVS2.

 

[BigblueC]

383 or 440? Split the difference and find a 413

 

[Racingsnake]

[QUOTE="Luke Pokrajac, post: 984353, member: 8080" I have a 383 in my sport fury and it runs just awesome with a Lunati 256 cam in it...more power than you would ever need. And it's pretty good on gas with a 650 AVS2.[/QUOTE]
Any idea what sort of mileage you get on the freeway?

 

[Racingsnake]

Thanks for the replies. I don't want to run a small block, I think the big block is a better engine and am not concerned about the work to swap the car over. The motor will be basically stock with shorty headers, dual exhaust and very mild cam. I might consider 2.94 gears but I find 2.76s are too tall.

Thinking about it, the '68 Coronet I had with a 440, mild cam, headers and spread bore double pumper Holley, 727 with 3.23 gears and 275/60x15s got about 15 mpg on the freeway so a 383 in the Fury should be able to get fairly close surely?

 

[70bigblockdodge]

Not with 3.23 gears. I get 15-16 with a 440 in a 68 Charger with a manual trans and overdrive .72:1 which removes 28% of the rpms at a given road speed.

 

[marko]

what about a gear vendors unit ? im not up on prices at the moment

 

[Luke Pokrajac]

[QUOTE="Luke Pokrajac, post: 984353, member: 8080" I have a 383 in my sport fury and it runs just awesome with a Lunati 256 cam in it...more power than you would ever need. And it's pretty good on gas with a 650 AVS2.

Any idea what sort of mileage you get on the freeway?[/QUOTE]
I got around 15-17 mpg with the 383 and 4 speed/3.23. Car now has a Passon Performance OD gearset...so final drive ratio is around 2.80 in OD. I got about 17-18 on a short trip...havent taken it that far on level freeway/country roads.

 

[413]

The problem with a 383 and or 2.76 gears & a 440 is you are giving away torque and you have a heavy car. Taking the engine below the power band. I like a 440 with 3.23 or 2.94 gears. You Already have tall tires so the 3.23 could work. Don’t get a low compression smogger engine. Just face it You will need to run premium

I had a 383 With headers and mild cam with 2.76 and it was a pig at 50-60 mph. Had to downshift to 2nd to pass a car. 2.94 was better, 3.23 was great. So it depends on the engine. Don’t be totally concern with lowering the cruise RPM, it could kill your engine, try a different gear.

it’s why I like a 440 or 413 better.

 

[HWYCRZR]

I have a’68 Polara with the 383-2 and 2.76 gears. I typically run around 70-80 mph. In many cases if on the interstate I would run 80. Last year I was getting around 13 mpg consistently per tank. Over the winter I sent my carb for a complete re-store. I haven’t had a chance to check the mileage yet this spring. It seems back in my college days when all hi ways were 55 mph and I kept it under 70. Not much city driving, I could get around 16- mpg.

 

[413]

I want to add my friend has a lower mile 1970 383-2bbl With 3.23’s and it’s surprisingly peppy. Maybe when these were newer and in good shape they had more power.

I’ve been on some 382-2bbls that were just turds with little power.

 

[HWYCRZR]

With the fresh 383-2. Mine will go. Will it burn rubber to 20 mph? No, but it get up to 55 pretty quickly. And from 55-85mph. Stomp it down, it kicks down and before you know it you are passing 80. Mph. Would a 4 bbl or 440 have more power? Likely, but I don’t like my tires to totally break loose when I romp on it.

 

[Mudeblue]

Sitting in my 65 Sport Fury and a women came up and asked me "what kind of mileage you get with that car?" My response, "if you want a classic car and your worried about gas mileage, you probably shouldn't own a classic and should be looking at owning a Honda Civic!"

 

[CBODY67]

Sitting in my 65 Sport Fury and a women came up and asked me "what kind of mileage you get with that car?" My response, "if you want a classic car and your worried about gas mileage, you probably shouldn't own a classic and should be looking at owning a Honda Civic!"

As a point of reference, I suspect that a late '60s 383 2bbl (or even a 2bbl converted to 4bbl) will get pretty close average mpg as a newer (2000-2015) full-size SUV gas vehicle that seems to be the rage for some drivers. Especially if its 4wd with off-road tires!

My point of references are our '66 Newport 383 2bbl/2.76 that would lay some rubber and still got 15mpg on a 80+mph trip out in west TX one night back when it was new. When I was going to college in Lubbock, the non-Interstate route (where the car had more fun!) was usually about 15mpg average in the 70mph range. The first trip I made with the then-new 55mph speed limit, I calculated it to be right at 20mpg at 55mph (not the whole trip, just the 55mph segments). That was also after I replaced the Stromberg WWC3 with a '70-spec Holley 2210 2bbl.

"Speed" is not kind to these cars due to their aerodynamics. My '70 DH43N would usually get about 16mpg on those same non-Interstate routes. With H78-15s/3.23 (25mph/1000rpm). Key thing is to "gear" for the fastest cruise speed to be slightly on either side of the peak of the torque curve (say 2600-3200rpm?). Which is why past 90mph, the '66 Newport had to exert more effort to cruise faster. Of course, the '70 DH43N had the normal 256/260 cam with, the "smaller" torque converter, HP exhaust manifolds, factory dual exhausts, and better aerodynamics.

"Gulftane" was a sub-regular grade gasoline, back then. Something like 91 Research Octane, when normal GoodGulf regular was about 94 Research Octane and Premium was in the 99-100 Research Octane range.

Enjoy!
CBODY67

 

[Rustyrodknocker]

I see no point in two barrel big blocks. You give up the big block pull in some sort of forced discipline.
A vacuum secondary 4 barrel with large secondaries give you the best of both worlds but the results will be tied to your self discipline.
Plus you can get that cool thermoquad quadrajet sound with an unmuffled air cleaner housing.

For daily driving I love a motorhome 440. Their cheap, run on junk gas and still put out big block torque. I don't care for 2:76's though I run them.
I'd rather drop a few mph and run a 3:00 rear gear.
And as mentioned your mpg will be on with modern suv's or the crew cab pickup family car.

 

[cbarge]

68 New Yorker 440..260/260 purple shaft,452 ported heads, 750 cfm Carter carb,TTi 2.5 system 3.23 gears 23570r15 tires...16.25 MPG

68 Newport, 383 bored .40 over Comp 268H cam 906 ported heads 750 carb Tti system 2.94 gears 23570r15 tires. 15.25 MPG

66 300, 383 625 cfm carb 452 ported heads TTi 2.5 system,all else stock with 2.76 gears 2157514 tires...18 MPG
But none of the MPG numbers were possible without FINE TUNING!
If you read everything, all my heads got work done to maximize flow for better torque and fuel efficiency.
A lot of trial and error, swapping jets and metering rods, recurving distributors, and many road tests only then you will know whatever engine and whatever parts WORK TOGETHER want to do, then you can achieve maximum efficiency. Happy motor, happy driver.

 

[Racingsnake]

Thanks for all the responses. I think a very mild 383 will probably get the job done.