so, i'm thinking about an engine build....

[tomslik]

i've aquired a virgin 283 (cast crank so...no 10K shifts) and i got to thinking....

hows this?
283 with MAYBE a clean up bore, 350 vortec heads (i'd try 305's but they're pretty scarce)with a tbi on the correct intake.
haven't decided on trans yet but maybe a 5 speed but most likely an automatic

kinda looking more for milage than anything else.
can't quite bring myself to drop a 4.3 in my coupe (48 chevy,9",MII)...

[rumrumm]

Check to make sure you won't have a problem with shrouding the valves using 350 heads. I know that is a problem using 350 heads on a 305 block.

[1FATGMC]

i've aquired a virgin 283 (cast crank so...no 10K shifts) and i got to thinking....

hows this?
283 with MAYBE a clean up bore, 350 vortec heads (i'd try 305's but they're pretty scarce)with a tbi on the correct intake.
haven't decided on trans yet but maybe a 5 speed but most likely an automatic

kinda looking more for milage than anything else.
can't quite bring myself to drop a 4.3 in my coupe (48 chevy,9",MII)...

I agree about shrouding the valves.  I have some stock heads, I think, that are 305's, there again I think about that also.  Let me know if you are interested.

Personally I would sell that to someone who is trying to make a period perfect car and build a boring 350.  More power and just as good as if not better gas mileage with an OD trans.  My truck gets better gas mileage than the....

 

............ the wagon I had with a 283.  I bought a slightly wrecked '98 van with a 5.7 and 4L60E for $800 that if I don't die first will go into the '51 Desoto Limo I have.  It will stay all stock and I'll bet it knocks down over 20 mpg on the highway.  

I could also probably get a wrecked suburban here for not too much with the newer 5.3 LQ motor and overdrive, but I'm shying away from it as it is even more complicated, but man can you make some power with those on the cheap.

c ya,

Sum

[OldSub]

Interesting idea.  I recently acquired a '61 283 that appears to have never been cracked open and I've been thinking about building it a an economical cruiser for use in a '57 Chevy wagon.  I'd like to knock down 25 mpg on the highway driving a big classic car.

[1FATGMC]

Interesting idea.  I recently acquired a '61 283 that appears to have never been cracked open and I've been thinking about building it a an economical cruiser for use in a '57 Chevy wagon.  I'd like to knock down 25 mpg on the highway driving a big classic car.

I hate to disagree, but I just don't see the 283 getting good (over 20 mpg) in a big car.  The secret to mpg is low rpm and the 283 doesn't have good torque at low rpm.  If you even look at the EPA mileage figures on the highway for 305's vs. 350's you will see they are the same and sometimes the 350's are even better.  Why give up the torque and power if there are no mpg gains?  You can't visually tell the motors apart in most instances, so run a 350 and tell everyone you have a 283   .

As I said I get 25% better fuel mileage with the 350/700R4 in my truck (19-20 mpg at 75) than I got with the 283/3 speed in the wagon at 65 (15-16 mpg).  The truck is no light weight at 4100 #.

c ya,

Sum

[OldSub]

I may be optimistic at 25 mpg, though I have a 350 in a 3500 pound car that will exceed that.  Of course that supports one piece of your point.

I've seen another '57 wagon do 16 and 17 on the highway with a stock 235, 3-speed and rear axle.  No overdrive.

Getting the car rolling is going to require gears deep enough to make up for the limited torque, but my thought was one of those 6-speeds with two overdrive gears could keep my highway engine speed quite slow.  My intent is to use EFI to allow running the motor efficiently at slow speed.

Are you are suggesting it won't have what it takes to keep the car moving efficiently once up to speed.  I suppose you could be right.

[tomslik]

well sum, i know what you're saying BUT using that logic tells me i shoul be building a stroked 400 sbc
keep in mind it's a smaller (and lighter)car than your wagon (and i LIKE that wagon, what happened to it?) and i was thinking 305 VORTEC heads.
they're not the same as 350 head or non-vortecs...
if i was worried about "period-correct" crap, it prolly wouldn't be getting a tbi.
why tbi?
already own it....
why a 283?
for the challenge of it...
not only that, it'll most likely get a 400 turbo behind it (see above) but if it DOES get an OD trans of some sort, i've got a 3.73 geared 8.8 out of an exploder....
i like the idea of bangin' gears but that's what the rambler is for

as far as "shrouding" the valves, i never had that problem with the last 283 i built but it was .060 over...and they wern't 2.02 intakes either



btw, i've got a 5.3 in my PU that'll get 19 and it weighs over 5000 lbs..and 4wd...areo as a barn...
i can ALSO tell ya what seems to be pattern failures with 'em


oh yeah,when i had the cpe running last with 3.25 gears and a 350sbc/400 turbo it got 10 mpg.
changed it out to a 700 and it got.....


drum roll, please....



10 mpg


plus i hated driving it with the 700...

had a 400/400 combo in it and it'd get over 20...

[reborn55]

A 283 can get upwards of 300 h.p. on a single 4 bbl carb and produce decent mileage.  I run a modified one in my 55 and it gets around 16 mpg--now that is with the original 3:70 gears and 4 speed.
Many years ago I built a handyman wagon with a 283--fairly stock, jetted down 2 bbl, turbo 350 with 3:08 gears that constantly got 20-22 mpg on the highway.  
I built it because it was in the 55 when I got it.  It is cheaper to build a 350 and might be easier to get the mileage, but what fun the 283 is at times.

[sirstude]

Just to add a bit more wood to Sum's fire.  When I put the 502 in my impala, I went  from 6mpg to 15 mpg.  I had a mildly cammed 325hp 396 in there before.  When you don't have to push it, the milage goes up.

Doug

[1FATGMC]

well sum, i know what you're saying BUT using that logic tells me i shoul be building a stroked 400 sbc .............

Yep,   .  I think the 350 just ended up being a good size motor all around.

............keep in mind it's a smaller (and lighter)car than your wagon (and i LIKE that wagon, what happened to it?) and i was thinking 305 VORTEC heads.............

Once up to speed on the interstate the weight hardly plays into the mileage.  It is all about aero then.  

I bought the wagon for I think $200 with the un-smart idea of using the chassis under my pickup.  It drove terrible, but then I found out that the gal that owned it had radials and bias plys mixed in different sizes and found out about sub-framing a vehicle and went that route with the pickup.  Meanwhile my computer business grew and I needed something for the service guys to drive and there was that wagon.  I did some really lousy body work on it and had it painted and used it like that for a couple years with the business.  Sold the business and sold the wagon to a friend in Moab for $1600 and he used it to haul his "Thrifty Nickel" newspapers around until he no longer wanted it and wanted to sell it back to me for $1200.  While I was thinking that over he loaned it to his daughter in Salt Lake and it was stolen never to be seen again.  Strange ending.

...............as far as "shrouding" the valves, i never had that problem with the last 283 i built but it was .060 over...and they weren't 2.02 intakes either............

Did you get in there and watch the air flow while it was running  

..............oh yeah,when i had the cpe running last with 3.25 gears and a 350sbc/400 turbo it got 10 mpg.
changed it out to a 700 and it got.....

drum roll, please....

10 mpg................

Did you ever shift it out of 3rd   ,

I'd better get out of here.........btw my heads that I think are 305's are the old style, but you could still have them, just promise not to throw them at me   ,

Sum

[enjenjo]

There is a big difference in bore between a 283 and a 305, 283  is much larger, only 1/8" less than a 350.

I had a bone stock 65 283 that would deliver over 25 mpg on a trip.

[Mac]

I'm trying to wring more MPG  (who isn't these days) out of my 283'd `63 C-10. I'm not stuck on the notion of period correctness but I like the small displacement. The plan is to put a T5 in place of the 3spd stick and adapt the TBI components from a 305. I read that the stock TBI intake leaves a lot to be desired so I'm going to try the throttle body on my Edelbrock Performer (dual plane 4bbl) with a homemade adapter. Eventually 350 Vortec heads after a .040 or more overbore and a cam change. I've heard the 305 Vortec heads don't have the good flow characteristics of the 350's.
As I understand it you'll get the best MPG when the engine's peak efficiecny RPM coincides with your normal, average, usual cruising speed. So, cam matched to gearing is critical.

[OldSub]

I had a bone stock 65 283 that would deliver over 25 mpg on a trip.

What was that in, and what transmission and rear gears was it using?  That sounds promising!

[enjenjo]

I had a bone stock 65 283 that would deliver over 25 mpg on a trip.

What was that in, and what transmission and rear gears was it using?  That sounds promising!

65 Biscayne, powerglide, 308 gear. 2GC carb.

[reborn55]

That would do it--great mileage and dependability