Slant 6 most mpg's

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I had that particular duster 15years ago. I do not know the rear end ratio, it was a 7 1/4 , no doubt, I raised back roads 50-55 all I ever did.
this rear should be 2.76 but i will double check it.
 
I have had several slant dusters, most were auto, and with GOOD engines driving strickly back roads at 50-55, I figured a good 20 mpg. upeers toward mid twenties, BUT it took a good engine, inc carb, dist, tuning....
I bought a 67 cuda 4 speed stock rebuilt 383 thermoguad back in mid 90's, it had been totally rebuilt( by an engineer for an oil co) that road raced another cuda. I drove it back to Mo from Ca, I remember it had a 2:94 8 3/4, and I averaged 18 on that trip running 60-70, sometime 75 across 2 lane Nevada........ desert, mountain etc.... BUT it was a GOOD engine!
 
I have had several slant dusters, most were auto, and with GOOD engines driving strickly back roads at 50-55, I figured a good 20 mpg. upeers toward mid twenties, BUT it took a good engine, inc carb, dist, tuning....
I bought a 67 cuda 4 speed stock rebuilt 383 thermoguad back in mid 90's, it had been totally rebuilt( by an engineer for an oil co) that road raced another cuda. I drove it back to Mo from Ca, I remember it had a 2:94 8 3/4, and I averaged 18 on that trip running 60-70, sometime 75 across 2 lane Nevada........ desert, mountain etc.... BUT it was a GOOD engine!
this is something i always believed. though alot of them were mutts and guzzlers.driving skills does alot.
 
OP, I drove a '76 Dart Lite 4 speed for about a quarter million miles. Stock, it got around 28 mpg at 65 mph in the mountains on the interstate. In the flat midwest, 29 mpg was normal for 65 mph. With the approx 400 lbs that they claimed to have taken off the car, it was plenty torquey. It would mildly ping on hills when lugged down in too high a gear but it never hurt anything.

I'd leave it stock. The only 'mod' made on my Lite was a vacuum gauge under the dash.... it sure teaches you fast how to keep your foot out of it.
 
THIS is what most people I've ever spoken to call it. Search Google you will find scads of info on "how to."

how to degree a cam - Google Search


"Centerlining" the cam, because You are setting the Intake lobe centerline in relation to TDC, that was the first reference term I heard for the operation. The second was
"degreeing", either way, checking the cam timing/position can help if You know what the cam centerline is supposed to be. Some replacement T-chain kits have been off
by an embarrassing amount...................
 
FiTech is planning to release a 2barrel sub-300hp system in "the first qurter of 2018"...

I would put it on a SL6 with out hesitation.
 
FiTech is planning to release a 2barrel sub-300hp system in "the first qurter of 2018"...

I would put it on a SL6 with out hesitation.
here's the # behind coil 6 225 R 21117 anyone know how to decode it? thanks
 
Change the speedo gear so it reads faster, that's always good for few more mpg's.

Although real world results may vary....
 
I think i can do better!
The challenge for You is that Mopar already "extreme mileaged" it for You, so improvements on the basic package are nearly impossible, the base timing for that package is
12deg BTDC(man & auto) vs. the std. 6(man) & 2(auto)deg BTDC. The carb. calibrations and timing curves are already pushing the envelope. If You are willing to run a
higher octane fuel, moving the compression up to 9.5:1 will probably be the only thing w/o a switch to FI and electronic engine management, to improve the stk. #'s.........
 
As stated, and it can't be hammered home enough, You're driving methods & skills are at least 70% of the engines ability to deliver efficiency..............................
 
As stated, and it can't be hammered home enough, You're driving methods & skills are at least 70% of the engines ability to deliver efficiency..............................
Alot of folks saying it Never got the 36 mpg it was rated for. So i will soon find out!
 
Alot of folks saying it Never got the 36 mpg it was rated for. So i will soon find out!
I'm interested to follow this along, don't rule out some aero experimentation, lowering ride ht. air dam/skirts etc..............................even the rake of the car can have
some effect............good luck!
:popcorn:
 
Alot of folks saying it Never got the 36 mpg it was rated for. So i will soon find out!
With todays blended fuel a gallon of gas is not really gallon of gas.

Engines are most efficient cruising at or near the torque peak in most cases. A V8 can pull off cruising at 2k rpm. Smaller engines not so much. Even most 4 bangers will pull better mileage buzzing 2.8-3k @ 70 mph then they will lugging along @2k.
 
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With todays blended fuel a gallon of gas is not really gallon of gas.

Engines are most efficient cruising at or near the torque peak in most cases. A V8 can pull off cruising at 2k rpm. Smaller engines not so much. Even most 4 bangers will pull better mileage buzzing 2.8-3k @ 70 mph then they will lugging along @2k.
 
Like Killer6 says i will be installing a front air dam n rear spoiler. also playing with the ride heights.
finding the happy spot in engine will be most interesting.
 
With todays blended fuel a gallon of gas is not really gallon of gas.

This ^^^^^^is the poor-mileage elephant in the room, as alcohol concentration goes up, the MPG's go down. I can't recall what year's we spent suffering with Gasohol in
the 70's exactly, but it's doubtful Mopar used it to calibrate & test these cars......................................................
 
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