1978 Grand Marquis

[farm]

Well done. I'm super excited for some videos!

[Grand1]

Well, I consider it a success....I had to relocate to another state, and drove her.
State to state was 350 miles, came out with a minor tranny leak....thats it.

The first 100 miles..... every sound, movement, gear change, etc caused panic and me saying "shit".
Then I relaxed and had a pretty cool cruze.
Kept her around 60- 67MPH, got 26 miles per gallon.

........... gonna need a higher stall torque converter....so much power to harness!

[Tiggie]

460 and 26 mpg? You must share your secrets!

[DerekTheGreat]

Mark!
Glad to see you posted on the barge dude! Where'd you relocate to?

No way you got 26 mpg out of a carb'd big block mated up to a treespeed lol. Either your math is off or the Speedo is or something. Our 454 GMC with its treespeed and 4.10's manages anywhere from 7.4-9.0mpg...

[Grand1]

460 and 26 mpg? You must share your secrets!

Thats keeping her low 60 -67....that is premium 93 octane gas so its not that cheap. NO smog shit at all...manifold and open pipes.
Unless I suck at math....didnt stop once for gas on 18 gallon tank....so 23 per gallon?

[Grand1]

Had to roll out dude....did that MAP sensor work for you?
Be back for the Dream cruise....you?

[pantera77]

got 26 miles per gallon.

[Kodachrome Wolf]

got 26 miles per gallon.

Keeping the Marquis at a steady 72 MPH once got me almost 400 miles and like 29.5 MPG. That was me trying to get decent mileage, otherwise I typically see 24-27 MPG highway.

I think your math is wrong if your 460 and 3 speed auto was doing that well. I'd assume something in the 13-17 MPG area. I might believe your original figure from a Box if it was kept between 55-65 MPH on gentle terrain since 65 and higher seems to really start sapping MPG on them.

[farm]

With all that extra power it has now it just idles on the highway I'm sure haha

[slack]

I feel like I am in an armoured vehicle....definitely would make one HELL of a getaway vehicle.

Haha. That's exactly how I feel in my '78. It's amazing how much beefier these barges feel than the panthers... and they're not really THAT much bigger.

Thats keeping her low 60 -67....that is premium 93 octane gas so its not that cheap. NO smog shit at all...manifold and open pipes.
Unless I suck at math....didnt stop once for gas on 18 gallon tank....so 23 per gallon?

Damn. That's really good. On my stock setup (351w/C4 with just a tune up & 2.47 rear gears) I'm only getting around 8mpg on 87 fuel. The carb is all sorts of out of wack but I'll be lucky to ever see your numbers. Congrats on the build!

[DerekTheGreat]

Had to roll out dude....did that MAP sensor work for you?
Be back for the Dream cruise....you?

I think it helped a smidgen. With 13° timing advance I'm seeing north of 16.5mpg on average when it was usually around 15.5mpg.

I just pulled out the Fireturd and drove it nearly 100 miles, we'll be at the dream cruise.
Are you coming up for that?

[Grand1]

Somehow my reponse to my gas milage never made it

...I was wrong..the trip I took was 210 miles..so it was 11.6 miles per gallon.

Recently I played with my carb setting including a new spring. I was fouling out plugs left and right
..my throttle response os even better
I need rear tires....need to convert to disc brakes as well

Has anyone ever upgraded or mod a C6? is a performance torque convertor ever been in the cards?

[DerekTheGreat]

He's alive!

I'll believe 11.6 mpg.

Might want to look into a rear end from a Mark V. Posi + discs.

[Grand1]

Whats up bro....long time no see
Hope you had a good cruise...intresting about the rear end...I dont know shit about differentials nor could turn a wrench to do so....I am amazed I got things done to this point

[DerekTheGreat]

Yeah man, how are the rides doing? Seems that the barge is still going strong. Cruise was OK, drove the Fireturd to it this year.

I know VERY little about them. I know even less about what the Mark VII's had going on but I want to say they shared the same platform as the Marquis' and LTD's, that or the T-bird/Cougar.. So, if it shares with the Ford & Mercury stuff the rear end should be or be pretty damn close to a bolt in swap. Been trying to read around and I can't find much info on them. Some guys say they're sought after and others say they aren't. Some say the Versailles also had a 9" with discs. Can't confirm that though.