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Topic: 86 GV 454 Chevy Gas Mileage (Read 275 times) previous topic - next topic

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86 GV 454 Chevy Gas Mileage
We have just returned from a 2000 mile round trip holiday journey to the Hill Country of Texas..  first time we were able to get an accurate reading of our gas mileage based on speed and RPM's....    at 68-70 mph ( 3100 rpm) just a 6mpg... but at...

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Re: 86 GV 454 Chevy Gas Mileage
Reply #1
Do you have a DIODE-BASED ISOLATOR?

If so, the "one wire" will not get adequate voltage to the batteries.

What is voltage at the batteries with  the engine running-- say around 1,200 RPM?

Re: 86 GV 454 Chevy Gas Mileage
Reply #2
Do you have a DIODE-BASED ISOLATOR?

If so, the "one wire" will not get adequate voltage to the batteries.

What is voltage at the batteries with  the engine running-- say around 1,200 RPM?

12.5 at...

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Re: 86 GV 454 Chevy Gas Mileage
Reply #3
13.5- 14 is just fine.  No need to dig further.

Sounds like you do not have a diode-based isolator as found on most Foretravels.

Re: 86 GV 454 Chevy Gas Mileage
Reply #4
13.5- 14 is just fine.  No need to dig further.

Sounds like you do not have a diode-based isolator as found on most Foretravels.

We are finding that we like the uncomplicated early versions of...

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  • Dub
  • [*][*][*][*][*]
Re: 86 GV 454 Chevy Gas Mileage
Reply #5
I've seen more than one 454 get 4 mpg in a pick up truck and I was buying the gas.. I've had a couple mh owners quote 10 mpg with that engine and my reply was ,if it makes you feel better believing that then good for you. If I were you I would be...

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Re: 86 GV 454 Chevy Gas Mileage
Reply #6
I've seen more than one 454 get 4 mpg in a pick up truck and I was buying the gas.. I've had a couple mh owners quote 10 mpg with that engine and my reply was ,if it makes you feel better...


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Re: 86 GV 454 Chevy Gas Mileage
Reply #7
I was a Chevy dealer truck manager 40 years ago and remember ordering a one ton 454 4x4 truck for a construction company.  Low geared tow setup,

Took  it for a drive before delivery.  OMG fast.

Had a buddy take out a vette to run with it.  Truck...

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Re: 86 GV 454 Chevy Gas Mileage
Reply #8
My friend lent me his 90's, four door 4X4 stick Chevy 454 dully for a week. He told me it got like 14 MPG. I laughed.
I went through 2 tank fulls with it. I was shocked, it got 15 MPG, I didn't baby it either
My 1990 2 wheel drive with it's fresh...

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  • Dub
  • [*][*][*][*][*]
Re: 86 GV 454 Chevy Gas Mileage
Reply #9
My friend lent me his 90's, four door 4X4 stick Chevy 454 dully for a week. He told me it got like 14 MPG. I laughed.
I went through 2 tank fulls with it. I was shocked, it got 15 MPG, I...


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Re: 86 GV 454 Chevy Gas Mileage
Reply #10
My only experience with the 454 was with a 4 bl carb.. I'm sure not saying I wouldn't buy a 454 because I would have a 70 Chevelle or Vette gladly with 454. I wouldn't give a rip what it got for...


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Re: 86 GV 454 Chevy Gas Mileage
Reply #11
If you keep it at 63  or lower you can get almost 8 in flatlands. Drag squares vs velocity.
  Those  went through fuel filtrs and  alternator belts. And exhaust manifolds. And front airbags.
 Still a cool cruiser , use it up.

Re: 86 GV 454 Chevy Gas Mileage
Reply #12
Our old SOB had a Dodge 440 and with the Carter AFB, got only 4 mpg after we bought it but improved to about 5.5 after the AFB was fixed. The change to a 7.3 turbo diesel and manual trans almost doubled the MPG. The rear axle ratio was pretty...

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Re: 86 GV 454 Chevy Gas Mileage
Reply #13
Our old SOB had a Dodge 440 and with the Carter AFB, got only 4 mpg after we bought it but improved to about 5.5 after the AFB was fixed. The change to a 7.3 turbo diesel and...


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