Garys72Duster
Well-Known Member
Yea, the mid 60s Mobile economy runs. That's when they were getting concerned about fuel economy, as gasoline prices were soaring past .15 a gallon! LOL
What mileage does your slant six powered ride get?
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doc540
Well-Known Member
Mileage reconfirmed:
50 miles
65mph
filled and refilled from the same pump
speedo correct
225 Slant
mild Clifford cam
Clifford intake and shorty headers
Holley 390
A904 auto
2.76 gear
185-70-13 tires
non ethanol 91 octane
24.5mpg
slantsixdan suggested I put a tad more timing back into it
as usual, he was right
plug #5
Slantsix64, I'm your huckleberry
50 miles
65mph
filled and refilled from the same pump
speedo correct
225 Slant
mild Clifford cam
Clifford intake and shorty headers
Holley 390
A904 auto
2.76 gear
185-70-13 tires
non ethanol 91 octane
24.5mpg
slantsixdan suggested I put a tad more timing back into it
as usual, he was right
plug #5
Slantsix64, I'm your huckleberry
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Slantsix64
Well-Known Member
Hold up there buddy, have you gotten a recurve on your Dizzy? What rpm range is all your timing coming in at IN,Mech,Vac?Mileage reconfirmed:
50 miles
65mph
filled and refilled from the same pump
speedo correct
225 Slant
mild Clifford cam
Clifford intake and shorty headers
Holley 390
A904 auto
2.76 gear
185-70-13 tires
non ethanol 91 octane
24.5mpg
slantsixdan suggested I put a tad more timing back into it
as usual, he was right
plug #5
View attachment 1715272852
Slantsix64, I'm your huckleberry
View attachment 1715272855
doc540
Well-Known Member
Slant's turning about 2600 rpm at 65 mph, so I'm not sure about the timing right there.
Stock '68 distributor w/Pertronix point eliminator kit, no recurve, no spring changes, no timing light.
Just an old gearhead's ear.
He's in assisted living now, but he can still hear good.
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Actually I think it was more the mind set of the people buying these cars new, my parents for instance. That generation grew up in the great depression and could be somewhat frugal.
I think it was valuable PR for car manufacturers to claim they won the Mobil Economy Run because that generation was listening.
I think my dad had 4 different cars with /6 power over the years. I still remember them shopping for a new car and I actually talked them into buying a new 1967 Dodge Coronet 440 white hat special with a 318!! Only V-8 they ever owned.
Garys72Duster
Well-Known Member
Yep, my Dad had a slant 6 in a Valiant. Ran great, and good on gas. My parents frugal ways got transferred to me. LOL. So we're still living with the save a penney mindset. Anybody have a cheap 383 intake for sale? Ha!
GenLee1970
Well-Known Member
In the fall 2016 I did a 5 week cross country trip (that included Route 66 ) from RI to California, part way up the Pacific Coast Highway then to Minnesota then home.
73 Dart with 1971 225, 2.76 rear, 904 trans, Holley 1920, points ignition, timing at 5 degrees, 205 75 14's. Car loaded with tools, parts, camping gear, survival gear etc.
Temps ranged from high 70's (southern portion) to 10 degrees (through Wyoming en route to Minnesota). Highway driving ranged from 55 to 70 mph. Lots of back road and city driving on Route 66 including 5 hours in LA traffic. Lots of hills and time spent at elevation car was not tuned for.
8,360 miles total. Average at the end of the trip was 19.7 mpg. Best reading was 21.9, worst was 13 in LA (lots of time idling then accelerating for an 1/8 mile to the next light so I could idle some more, accelerate, idle, repeat.)
73 Dart with 1971 225, 2.76 rear, 904 trans, Holley 1920, points ignition, timing at 5 degrees, 205 75 14's. Car loaded with tools, parts, camping gear, survival gear etc.
Temps ranged from high 70's (southern portion) to 10 degrees (through Wyoming en route to Minnesota). Highway driving ranged from 55 to 70 mph. Lots of back road and city driving on Route 66 including 5 hours in LA traffic. Lots of hills and time spent at elevation car was not tuned for.
8,360 miles total. Average at the end of the trip was 19.7 mpg. Best reading was 21.9, worst was 13 in LA (lots of time idling then accelerating for an 1/8 mile to the next light so I could idle some more, accelerate, idle, repeat.)
aaronk785
Well-Known Member
About 15 years ago my mom came up from Mississippi in her 73 slant dart. It wasn't running well to I tuned it up for her. Don't remember where I set the timing but I rebuilt the carb, put on new wires and plugs. On her way back home she swears she got 32 mpg. These were all highway miles and she never drove over 50mph. She was a nightmare on the interstate. I guess its possible.
I get any where from 11 to 14 mpg . 904, 3.23s. 28" tires on back in my van.
arvzj
Member
'65 Valiant V200 wagon, with virtually the entire innards of several '76 4-doors transplanted into it: 8.25" 3.23 rear end, A-833 OD 4-speed, stock '81 225 with Carter BBD two-barrel manifold, custom hot advance curve, MSD 6A ignition and coil (surprise, way better than the stock box!), Bosch plugs, 1 7/8" exhaust system, dual-circuit brakes with the '76 control arms and disc brakes, 340 torsion bars, front and rear sway bars, KYB shocks, extra leaf and overload springs on the back because I carried tools and parts a lot, synthetic lubes, top-cylinder lube in the gas, 44 psi radials at 38-44 psi depending on the load, full thrust alignment with less toe-in and more caster. 1994-2015 I drove this remanufactured rig about 340K miles in Oregon, Washington, Idaho, and Montana, mostly energy-efficiency related audits and research projects. Correcting for speedo error, multiple fill-ups: standard highway mileage was ~25 MPG. If I kept the speed under 55 mph for the whole trip, it would do ~27 MPG.
At an apartment complex energy audit on the Oregon coast, I met a retired Chrysler engineer who saw my car and when I told him what running gear I had, he said, "25 MPG, right? That's what we designed the cam to do!"
That '65 wagon rusted away after 50 years as a daily driver. After I retired I did another complete parts transplant into a very pretty '64 V200 wagon a friend gave me, so now that running gear with 340K miles since the original overhaul is in another car. The A-833 (extra ATF to cover the top bearing) and rear axle seem fine, that '81 engine has normal compression and oil pressure (although I did put another head on because of valve seal problems, and a new cam chain set at ~260K, it ran fine although the highway gas mileage had fallen to `22 mpg). I used the 225 that was in the '64 because it only had 120K on it. The '64 is still major fun to drive, and I put a set of Wheel Vintique 6x15 Rallye wheels with 185/65/15 Continental True Grips on it recently. These look like the largest tires you can run on a 64-66 without any rubbing at all, and should be available for awhile because the '06 Prius generation uses this size. Seems like it is getting hard to find top-end tires in 14" sizes. In 2016 this specific Continental out-performed the Michelins in on-vehicle tests, but I should say Michelin tires saved my bacon many times. I always had to show up for appointments with no regard to the weather or season. I never regret spending a few extra bucks for the best tire I can find. Nokians usually end up on top these days.
Irrelevant to the good gas mileage, but the '65 still has the stock AM radio, which has a great tuner section that would pull in stations these modern phase-locked-loop radios can't even find. Here is a tip for the generations: in the old AM car radios the main output transistor is often ballasted by the radio light bulb. When the light bulb burns out, the main output transistor burns out and the radio dies. So you can find a new Si output transistor with bulletproof specs and solder it into the circuit board, replace the light bulb, and the radio will last 50 years at least.
At an apartment complex energy audit on the Oregon coast, I met a retired Chrysler engineer who saw my car and when I told him what running gear I had, he said, "25 MPG, right? That's what we designed the cam to do!"
That '65 wagon rusted away after 50 years as a daily driver. After I retired I did another complete parts transplant into a very pretty '64 V200 wagon a friend gave me, so now that running gear with 340K miles since the original overhaul is in another car. The A-833 (extra ATF to cover the top bearing) and rear axle seem fine, that '81 engine has normal compression and oil pressure (although I did put another head on because of valve seal problems, and a new cam chain set at ~260K, it ran fine although the highway gas mileage had fallen to `22 mpg). I used the 225 that was in the '64 because it only had 120K on it. The '64 is still major fun to drive, and I put a set of Wheel Vintique 6x15 Rallye wheels with 185/65/15 Continental True Grips on it recently. These look like the largest tires you can run on a 64-66 without any rubbing at all, and should be available for awhile because the '06 Prius generation uses this size. Seems like it is getting hard to find top-end tires in 14" sizes. In 2016 this specific Continental out-performed the Michelins in on-vehicle tests, but I should say Michelin tires saved my bacon many times. I always had to show up for appointments with no regard to the weather or season. I never regret spending a few extra bucks for the best tire I can find. Nokians usually end up on top these days.
Irrelevant to the good gas mileage, but the '65 still has the stock AM radio, which has a great tuner section that would pull in stations these modern phase-locked-loop radios can't even find. Here is a tip for the generations: in the old AM car radios the main output transistor is often ballasted by the radio light bulb. When the light bulb burns out, the main output transistor burns out and the radio dies. So you can find a new Si output transistor with bulletproof specs and solder it into the circuit board, replace the light bulb, and the radio will last 50 years at least.
valiantwagonguy
Well-Known Member
My 65 Valiant wagon with a 170 with a 4 speed from a 65 Barracuda with 1to1 final drive and 323 rear gets around 24 on the highway fully loaded with all my camping gear and tools ( lots of weight) A 225 in the same car with the same set up got around 18.
That's amazing how much better the 170 does on the highway. Your experience with the 225 mirrors mine; I get around 18 or so on the highway, but my car originally had a worn out 170. I guess the little bit of extra power is a fair enough tradeoff.
valiantwagonguy
Well-Known Member
170's are the greatest little motors for a driver.With a 4 speed behind it (not an overdrive one) they are lots of fun to drive. That little short stroke motor is very responsive when you set it up with the right trans and rear.
I'll agree with that. I had a souped up 170 behind a O/D manual in a 64 Barracuda. Ran great, unbelievable mpg and good power.
my68barracuda
Well-Known Member
Slant powered 1983 D150 towing the slant powered 1968 Barracuda to a race.
The slant in the D150 was built for low rpm torque. It has 3.73 rear gears in a 8.25 differential. A833 OD tranny. Holley 2 bbl 2280 carb, dual Dutra's, free flowing exhaust, HEI ignition, cold air intake to the carb, electric fan,,,,
When towing on level ground running 65 mph AC and cruse on it will easily get 15 mpg. In hilly terrain/mountains, the mpg and the speed drop, a lot.
The towing is helped by the lightweight aluminum trailer and the Barracuda being totally stripped out inside.
When running solo the D150 will get 20 mpg, if I stay in the right lane on the highway at 65 MPH or below.
Run in the left lane 70 to 75 + and the MPG drops to the 16 to 17 range. These trucks are aerodynamic bricks.
In town / stop and go driving it gets 15 to 16 mpg.
The slant in the D150 was built for low rpm torque. It has 3.73 rear gears in a 8.25 differential. A833 OD tranny. Holley 2 bbl 2280 carb, dual Dutra's, free flowing exhaust, HEI ignition, cold air intake to the carb, electric fan,,,,
When towing on level ground running 65 mph AC and cruse on it will easily get 15 mpg. In hilly terrain/mountains, the mpg and the speed drop, a lot.
The towing is helped by the lightweight aluminum trailer and the Barracuda being totally stripped out inside.
When running solo the D150 will get 20 mpg, if I stay in the right lane on the highway at 65 MPH or below.
Run in the left lane 70 to 75 + and the MPG drops to the 16 to 17 range. These trucks are aerodynamic bricks.
In town / stop and go driving it gets 15 to 16 mpg.
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I get in the area of 24 miles to the gallon in my stockish 71 valiant 4 door. I say stockish, because it's got a pertronix ignitor.
The way I measured is by knowing a fixed distance between two points (not city driving), and filling my tank up immediately at the beginning and end of the trip. So I know I'm 100% full when I start, and I know exactly how much fuel it takes to make me full again (spilling out the fill hole).
It's consistent too. I've done it multiple times. I kept receipts while doing it. None of it relies on the speedo, odometer, or fuel gauge.
The way I measured is by knowing a fixed distance between two points (not city driving), and filling my tank up immediately at the beginning and end of the trip. So I know I'm 100% full when I start, and I know exactly how much fuel it takes to make me full again (spilling out the fill hole).
It's consistent too. I've done it multiple times. I kept receipts while doing it. None of it relies on the speedo, odometer, or fuel gauge.
Nigel Hely
64DartDownUnder
Damn! I only just threw out all my calculations the other day, we had done a long trip, I recorded all the details... 1964 Dart GT, stock 225, automatic, 2.93 diff gears, 2 1/4" exhaust, 225/60/14 tyres.
The end result over about 350 miles of highway/country roads driving was average about 23.1mpg (19.68L/100km). Note: that's using real-deal UK Gallons, not "Diet Gallons" HaHaHa!
The end result over about 350 miles of highway/country roads driving was average about 23.1mpg (19.68L/100km). Note: that's using real-deal UK Gallons, not "Diet Gallons" HaHaHa!
moparblood
Well-Known Member
just starting driving my Dartlite, so far 26.6 mpg's on average (highway) i will soon start tweaking, and give up date.
chinze57
Push Button tranny and a Slant 6 that'll never die
Where are y’all getting 91 octane no ethanol? Quiktrips near me have 85 octane no ethanol, and same at a local Shell. Octane boosters? How will a higher octane affect fuel economy?
valiantwagonguy
Well-Known Member
I can get 93 non eth upstate NY near the Canadian border but down anywhere within 200 miles of NYC there is NO NON ETH gas to be found
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