I know of a 327 w/700 stock geared in a '65 Chevelle daily driver 20+ Another Chevelle warmed up 350 w/700 4.10 gear 19 with the holley 22 with the quad at 80mph. lots of it is determined on the weight of the car also your cam profile don't forget driving style. You can determine your rear gear by your tire size RPM range you want the motor to rev at cruising on the Hwy
mileage will be based on more info than cid and an overdrive. my experience has been, a normal sized hot rod (2000-2700 lbs) running under 400 hp can get 20-25 mpg if your cruising rpm is around 1800-1900. it helps A LOT if your motor is tuned well. here is my best tool to figure out what gear you will need to get the rpm you want. http://wahiduddin.net/calc/calc_speed_rpm.htm there are several overdrives available, all with different final drive ratios. knowing what transmission you are using and what final drive ratio you have is a must. for example: i built a '32 roadster for my mom. she is running a zz-3 chevy crate motor with a g.m. hot cam kit and 2 500cfm carbs. it also has a t-5 5 speed with a .68 final drive ratio in 5th. i estimate that motor at 395 hp. the rear end ratio is a 3.50:1 9" ford, along with a 31" tall rear tire. this combo has resulted in 24-26 mpg on several trips. the key to mileage, is to cruise right below where the motor starts making power. using the website above, this combo is 1800 rpm at 70 mph or 1950 rpm at 75 mph. hope this helps. -danny
This one is not a Chevy and it is a factory 292 OD I believe it came with a 4.11 but I never checked it out fully. I never checked the mileage either but it was not bad. It was a blast to drive around town with the lower rear. I never tried for mileage. I was having too much fun winding it up in each gear and letting the engine slow the car down. Not good for mileage but still fun. I am currently building a 352 powered 56 Ford with a 3spd OD trans that it came with. I never have checked the ratio. Notice the relay on the firewall. I'm guessing it is a 4.11 also. If I ever change it to a 9" I'll go for a 3.55 or a 3.73 which seems to be a more modern choice for a V8 automatic OD rear.
I used to laugh at my buddy who had a t bucket with a 283 and a plain 4 speed the little thing was lite and fast and if he kept his foot out of the carb he could cruise all night on a couple gallons of gas where my 455 firebird would use about 10 gallons but gas was 79 cents a gallon so it didnt really matter same as today I would not build a street rod to worry about fuel economy a clean running 283/overdive with electronic ignition and a well tuned carb should be able to deliver well over 20 mpg city in a lite rod I remember a article about o/t fox body mustangs getting better city mileage by installing 3.73 gears over the 3.08's they came with when they had a 5 speed in front of them
Back in the day, 3sp w/OD would have 4.11 rear. One of my uncles had a 53 Mainline, would do 110 in 2nd over, not any better in 3rd over. Mileage?? Use the vacuum gage, that will provide useful information related to proper gearing.
hey guys--I had a 58 c10 a few years ago with a 307 2bbl & a3spd o/d from a 55 chev car had the stock 3.91 geared rear & got 22mpg on hiway a little less in city had 235/75 tires on 15 by 8 inch ralleys
A 283 in a light rod should do 20 MPG easily.Having said that there is a trait that concerns me with the 283 and using an over drive... My experience was this- the 283 had precious little tourque on low end RPMs. thus one will see s drop in mileage below 2500RPM in OD.... if you are not careful it will end up being a situation that lets the engine run below 1800 RPM at say 70 MPH. this will actually lose you mileage rather than gain it. that will end up making you have to run 85 MPH to reach perfect RPM/ mileage for that motor....= tickets out the yingyang Ideally 25- 2700 RPM is optimum cruise RPM for peak mileage.....[at speed limit mind ya]
When I was a kid, I had a '58 Apache with a stock 283 with a 2 barrel carb, and three-speed trans with factory overdrive, 3.73 gears. I'd usually get about 25mpg going between L.A. and San Diego. Cruised nicely at 65 mph. That was back when you could actually drive at 65 mph all the way down to the border...
I get 28mpg with a 5lt, 700R, 3.55:1 gears and 235/75/15 tyres in my '35 phaeton. Cruises at 2K rpm at 60mph
I'm running an Avanti R-1 289, Chevy saginaw 4-speed with a Studebaker OD, 3:31 gears. 80MPH / 2400 RPM with A/C blasting I get 21 MPG. Swapping out the rearend for a 3:73, doubt it will affect the MPGs.
I agree, not many folks understand that you have to keep your engine in its operating range to get decent mileage. A couple of years ago I built a .040 283, single 4, 9:1 and a Lunati RV cam, power pack heads; that went into a '60 El Camino. It had 4.11:1 gears and a 700R4 built by Pheonix just for the car. 22 mpg on the highway @ 80. 20 @65. Hope this helps.
I'm a fan of the lil 283's I had a big 68 biscanyne 283, 266 crane energizer, performer rpm, 600 eddy, 305Heads(58cc) 3speed with 3:36 gears with 255/60/15's on back. I cruised at 65mph at 2000rpm and got almost 23mpg my first tank to LSR. I was really surprised. I took another eddy carb and messed with it. changed jets, rods. It was getting 17mpg in town and over 20hwy I have a PROJECT 58 yeoman 235, 4:11 gears with 3 speed OD. I have a rebuilt 283 short block and a set of vortec 305 heads. I am thinking of around the same cam, maybe even a 500 carb and seeing what can be done with mpg.
The main point has been made, 1600-1800 rpm is great for a flathead (4" stroke), or maybe a 70s, 80s smog motor 350, but the little 283 is 3" stroke. OD is great on this engine with a 3.7 to 3.9 rear gear and the car is more fun to drive. My uncle had a '58 wagon with 3 speed trans and he would get 18 mpg at 60 mph... pulling a 16 foot camping trailer.
Thanks guys,I had a 283/powerglide in a Hiboy 32 p/u,It was stock,Now I have a 50 Chevy p/u and drive all over,Gas is over 4 dollars a gal,I'd rather spend the cash on something else,Thanks for the info,Lucky
I had a 283 with a saginaw 3 speed and over drive outa a 57 chevy and 3.9 rear gear in my 1962 Austin Healey 3000 it weighed 2000 pounds and would go zero to 60 in less than 5 seconds and I was never brave enough to push it past 125 mph. If it would pull the gear I figure it was good for a buck and half or more if driven by someone with bigger nads. I got 20 plus mpgs just coasting around. i sorta miss that car now.
I have the 283 w/ 2bbl Rochester + Flight-o-Matic in my 65. Glad I stumbled on this thread. Pretty light car. I'm interested to see what kind of mileage I see out of it this summer. It will be my daily driver for the summer. Was thinking about dropping an OD Trans in it next winter depending on how it goes this summer. Other idea was a 500cfm 4bbl. I will be doing my research and plenty of reading on the subject until then.
Gentlemen, I just got my hands on a 1990 700r4 that has a shift kit and all that. Going to smack onto my '67 283......Is it worth it to put a tranny cooler on it? Or to put the special pan with tubes running through it to keep 'er cool? Oh by the its going onto my '61 chevy truck with a '73 C10 frame....and im not a racer so I'll be cruising it but probably will punch it to pass... Im new to the 700 but I've great things about it compared to the 350 I was going to run on it. Thanks
Dad's 62 Nova with a 283 / 700R4 / 3.55 gears has awesome driveability and is perfect in a smaller car, not sure I would go with the same combo in something heavier though.
Thanks for the info....What cooler do you recommend(brand etc.)? Do you know of a good resource that dumbs down how to set up TV correctly? Or should I have a "pro" do it? Thanks again..... el_bole
Gee, how long is a piece of string. I run my lines through the bottom of the radiator and then through a separate auxiliary cooler before going back into the transmission. Not everyone does this however a reputable shop recommended this to maintain transmission longevity. I could get away with radiator and leave it at that. Insofar as TV cable is concerned you need an accelerator bracket to suit to maintain correct fulcrum with the OD cable and carburetor at wide open throttle (WOT), only $20. As stated with these transmissions you run a higher ratio rear end to compensate for the 30% OD. Lots of variables, tyre height etc, weight of car.
I'm interested to know this, too. I am setting up a 283 4bbl with a 700R4 in my 1959 Impala 2-door hardtop and I just installed a set of 3.70 gears in it. I figured that would be OK... I don't have enough engine to run 3.08 (which is what was in it with the Powerglide), 3.36, or 3.55. I have 4.11's but... I think the 3.70's I got should be ideal. I'm hoping to get 20mpg if I stay out of the throttle.
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