What mileage does your slant six powered ride get?

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idk exact mileage as speedo don't work but my D150 /6 833od gets double what my chevy 1/2 ton 350 auto did! and got bout as much power!!
 
Thanks brother!

Ahhhh man! Remember when I first had the /6 in that ‘74 Duster and I was getting 19-ish in the Hwy? The old timers were beating me up on not knowing how to tune the engine and get what they were claiming, 30, 32, 35+ mog’s.

I never believed that **** but! When they were new and the big 3 had mpg Competitions ......
Doubt they can even get 25. With an od and 2.76 in the real world 16-18 auto stick 18-22
 
A-body, 225, 904, 3.23, 2bbl Carter with 2-1/4 exhaust. Gets 15-18mpg on road trips with two people and luggage, mostly back roads. Would get higher on the freeway if I kept it at 60 or less, but that never seems to happen. Aerodynamics is a b****.
 
A-body, 225, 904, 3.23, 2bbl Carter with 2-1/4 exhaust. Gets 15-18mpg on road trips with two people and luggage, mostly back roads. Would get higher on the freeway if I kept it at 60 or less, but that never seems to happen. Aerodynamics is a b****.
Rpm below 2000 is the key.
 
1961 Lancer
A904
2.73 rear
Pertronix ignition
Head work, mild cam, Clifford intake and shorty headers, Holley 390
91 VP non-ethanol

24mpg highway, 65mph

lancer ranch1.jpg
 
My Slant running on a good day gets around 18 to 22, w/ Mopar elect. ign., Super Six mod, headers, dual exhaust. 904 Auto. and 3.23 gearset in an 8.75 center chunk. 87 at the pump.
 
Doubt they can even get 25. With an od and 2.76 in the real world 16-18 auto stick 18-22

Best mileage I've recorded is 20.5, that was with me, my teenage son, a mountain bike, and 75 lbs of tools in the car. It was also before I rebuilt the carb, and dialed in the rest of the tune...

I'd be willing to bet that I'd get 22 mpg now with the car similarly loaded. 25 wouldn't be difficult with some real care paid to tune-up, tire pressures, etc.

And this is in a wagon, which has to weigh a few hundred pounds more than a 2-door sedan.

I think 25 mpg should be obtainable by most /6 A-bodies, 30 would be pushing it, and 30+ should be reserved for the best LSD trips.
 
Some "points of reference" from back then

Friend of mine had a stock 69? Charger with a 318 routinely got OVER 20 mpg on a trip from San Diego to LA (We were both in the Navy, then)

The ill-fated 440 in my 70 RR (was a 6bbl, had a Holley 800/ Edelbrock/ headers) would get 13.8 and that was with "my driving" which was not "careful." Later I swapped a 340 into the car and it would get 17 1/2 plus, routinely. Again, not being very careful. "Getting on a ramp" was not an idle out onto the freeway deal

OTHERS HAVE MENTIONED ^^ timing!!! The 0 BTDC was fro SMOG and no other reason. Search up on what sort of performance advance curve you really want for a slant. One start would be to look up specs for the distributor on a 65/66 slant which is BEFORE emissions. Remember that distributor degrees is HALF crank degrees. Get your distributor set up with a shorter curve

Also make sure the distributor is actually in good shape........Worn bushings and advance mechanism can CHANGE the evident advance curve, along with a busted vacuum advance.

Check the ACCURACY of your timing marks..........piston stop

Exhaust...........Even a low HP vehicle can benefit by a good exhaust, working properly.....no frozen heat riser, etc etc

Fuel........A good properly jetted, properly adjusted carb......including the choke will make a tremendous differenc in fuel mileage. "I ain't the expert" on specifics of slant carburation

The last thing to consider THIS IS JUST an example. Years ago, l a friend had a big 'ol heavy 68 Chev 'Burban, had a 292 six. Got XX mileage, he thought it was terrible. I think it was 12, 14, ?? He spent ALL kinds of time and money converting it to a 283, and guess what?? IT STILL GOT terrible mileage and didn't have ANY more power than when he started.

The point? Sometimes you can shoot yourself in the foot!!!
 
Personally, I think if you can break into the 22-23 area you better leave it alone!!! That will not be short trips or around town.
 
I think Woody is running 14-32's on his coupe. He's an old drag racer and the thing is tubbed. I sent him a message but haven't heard back yet.
 
I drove to Carlisle in 2017. Filled up right before I got on the Ohio Turnpike and refilled when I got off the PA pike exit in Carlisle. I think it was 320 miles and the last 3 hrs was through a driving rainstorm up and down the PA hills.

1964 Val convertible, top up, 3.23, 7-1/4, 3 speed manual, 195/70 X 14 Kumho radials, fresh and completely rebuilt 225, rebuilt head with pocket porting/gasket match by me and milled .080, mild Oregon regrind, stock rebuilt BBS, breaker point ignition, about 8* initial timing, 2" single pipe.

I tried to keep it steady at 65 even through the deluge and passed everybody in the rain when the lesser vehicles slowed down.
23.8 MPG on one tank.

I was disappointed when I drove the 6 hrs to Clay City, KY this September but was in a hurry and only got 22 going down. Didn't check going home but it was driving through the remains of a hurricane.
 
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I drove to Carlisle in 2017. Filled up right before I got on the Ohio Turnpike and refilled when I got off the PA pike exit in Carlisle. I think it was 320 miles and the last 3 hrs was through a driving rainstorm up and down the PA hills.

1964 Val convertible, top up, 3.23, 7-1/4, 3 speed manual, 195/70 X 14 Kumho radials, fresh and completely rebuilt 225, rebuilt head with pocket porting/gasket match by me, mild Oregon regrind, stock rebuilt BBS, breaker point ignition, about 8* initial timing, 2" single pipe.

I tried to keep it steady at 65 even through the deluge and passed everybody in the rain when the lesser vehicles slowed down.
23.8 MPG on one tank.

I was disappointed when I drove the 6 hrs to Clay City, KY this September but was in a hurry and only got 22 going down. Didn't check going home but it was driving through the remains of a hurricane.
25 @ 55mph I bet.
 
Best mileage I've recorded is 20.5, that was with me, my teenage son, a mountain bike, and 75 lbs of tools in the car. It was also before I rebuilt the carb, and dialed in the rest of the tune...

I'd be willing to bet that I'd get 22 mpg now with the car similarly loaded. 25 wouldn't be difficult with some real care paid to tune-up, tire pressures, etc.

And this is in a wagon, which has to weigh a few hundred pounds more than a 2-door sedan.

I think 25 mpg should be obtainable by most /6 A-bodies, 30 would be pushing it, and 30+ should be reserved for the best LSD trips.
With a wagon? 22? My girlfriend has a wagon 65 valiant she drives slow and never floors it probably five miles under the speed limit she doesn't even get 20mpg maybe 17 at best. Motor and trans rebuilt stock one barrel 3.23 gear in the rear.
 
I drive mine mostly during the colder months, and it gets 15-17 in mixed driving. It has 3.23 gears, a Holley 1945 from a '75-'80 car (NOS in the box, never even took it apart), 2.25 exhaust, 5* initial, electronic ignition, and a three-speed. I run the distributor that came with the engine, which is a '74 225 out of a Charger (of all things).
 
In 1978, my 1970 Doge Dart Custom got 17mpg. I know because I was reimbursed for mileage. 225, 904 with 2.73 gears and E60x14 tires. The car had 120,000 or so miles on it.
 
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