Better gas mileage

[pjude]

Hi! I have read several posts about you guy's getting 8+ mpg. When I bought the 345 I was getting 6mpg with toad and genset running. New plugs, wires and tune up and still get 6mpg at 2800 rpm without toad and without genset.
This unit has the Banks system and from what I have read I should do better than 6 mph. New carb maybe? any suggestions ...at today's gas prices I spend a lot of time just looking at it rather than using it.
Pete

[cajuncruiser]

Pete, I have not driven enough to get a measurement yet. I'm curious to find out and hope I'm on the good side of 6mpg. Let you know.

[Robfike]

We get 7 to 7.5 mpg without genset 95% of the time with our '86 345.
Rob

[345bill]

we get 6-6.5 with our carberated 454, 89 345, but it gets much better on long downgrades,haha. Seriously though we have owned our 345 less than a year, did major tune up shortly after purchase, put about 12,000 miles on it so far and the more i'm learning how to "drive" it the better the gas mileage seems to be getting.

[klattu]

6 mpg is what I get on the Interstate...almost exactly.
Mostly because I can't keep it under 75mph.
Thats without pulling anything, and no gen, I think. (was October)

If dropped down to a max of 65, it gets 7.3 mpg.
(Sure was more fun at 75)

On two lanes, with a max of 55mph, it gives me 8.6 mpg.

This was all from a long road trip, with many fill ups, so I trust these numbers.
I don't have Banks.
Regular duals all the way back.

[ralley]

All: I posted this earlier, and copied it here as more germaine.

Over Christmas, we visited Virginia Beach, VA, driving from there to Southern Maryland with wife, dogs, and full tanks of fuel but no water or sewage. Between Virginia Beach and the fuel stop just short of the VA-MD line on US 301 we used exactly 11 gallons of fuel, covering 165 miles--which I make to be 15 MPG, @ $2.79 per gal. Averaged about 50 mph--heavy traffic in places.
We stayed over an additional day while a fresh storm with 40 mph winds blew through--QED

91 350 LE
454
MSD ignition
Gearvendors
Headmans

Driving mostly by cruise control, mostly flatland.

Best to all,

Rob

[M Hohnstein]

We have a 87 345 w/reman 454, Edelbrock Performer intake, ceramic coated headers, 700r trans/w GearVendors, tow a 240D Mercedes and cruise 65/70, 2500 rpm, dash air running get 6.5. Using the stock carb unmodified as the engine runs like a watch haven't changed it. Doubt there would be much improvement with a different carb. The mufflers are round reverse flow, don't know what kind. The geezer I bought the coach from took exceptional care of it, until the engine blew up and it cost him 8 grand to repower it.
He claims it always got over 8 with the old engine, but he talked about cruising it at 75 mph too. As I installed all the transmission upgrades, he was a buzzing the rascal, and I suspect he was as he suffered a valve train failure that necessitated the engine replacement. I have towed over a quarter million miles with big block powered Chevrolets of various chassis combinations, always got around 6. I suspect if one really tries to drive like there is an egg under the gas pedal, better mileage is possible.
I ditched the air pump, tubes and the basket of snakes vaccum lines, really cleaned up the engine room, rewired the 12v with a bunch of new circuit breakers, added a race car starter cause I like the sound they make. I wonder if I hurt the mileage a little, cause it's got great power now, that I like to use. I think that's what happens when one buys a Banks. Never hear about anyone getting better mileage with them.
I should mention the IPD sway bar and urathane bushing kits really took care of the handling issues. A great investment.

[jking]

To "M. Hohnstein" - please tell me about those Urethane IPD sway bar bushings - I need to replace mine as they are totally perished.
Thanks, Jamie

[geirws]

I have a 1977 24ft argosy MH I get 9.5 to 10 mpg (imperial gal.)

[2airishuman]

Originally Posted by jking

..please tell me about those Urethane IPD sway bar bushings - I need to replace mine as they are totally perished.
Thanks, Jamie

hi jamie

here's a thread with the basic info and a link to one vendor...

see posts 2 and 6 (or read it all)

http://www.airforums.com/forums/f160...ngs-35545.html

it's interesting to see the dismal mpg reports but a good reality check none the less...

i've still got my travel/maintenance/mileage logs from a stock 79 28/29ft a/s moho with the 454...

the average mpg was usually around 7.8-8.5 in those years and sometimes driving, really fast...

did all the typical mods after about 10 years (high flow exhaust, dt headers, air/intake, gearing, airdam, suspension, plugs/wires...

and always ran the tires at high pressure...

after the 'banks mods' the mpg didn't change but she did run cooler and quicker up to speed.

slowly as the years (and miles) passed, mpg declined some to the low 7s after 20 years of service...

i've always wondered it this was fuel quality related, an early sign of engine fatigue or some other process...

the ipd suspension mods were VERY noticeable and well worth the costs...

cheers
2air'

[68 Overlander]

Given the engine, weight and age, I'd be bragging about 8 or 9.

[jking]

TNX for the info on bushings - I'm ordering a full set of replacements for my IPD bars today. BTW I actually get 10-12 mpg towing ('84 310 with the 6-banger Isuzu diesel towing '07 Toyota Yaris) but I seldom drive over 60 mph.
73, Jamie

[Warbs]

I guess I'm getting old but I usually drive at 55 to 60. My old bus seems to have a sweet spot just below 3000rpm so I try to keep it there. My mileage has been up to 11 per imperial gallon and as low as 4 through the mountains. It is usually just under 10 per imperial gallon (about 9 per U.S.)

[elbundi]

what's all this about? take a look @ PICC (pre ignition catalytic converter)
am i being hoodwinked by the techno garb?

can you image 8mpg x 9 (best effort) 72 MPG! for a 345 that would be awesome

i keep getting an error on the form for a quote though.

[rmpray]

I thought the MH would do better than a large trailer truck combo, but I get 12 with my old rig. True, it is diesel so that is more like ten when ya factor in differece between gas/diesel, but people still stare

[GlenCoombe]

Interesting ..... I could handle doubling my mpg. One of the testimonials was ...
“My mechanic installed the HAFC Kit on my 1998 Airstream Motor Home and it went from 6.8 mpg highway to 22 mpg. My friend was with me on the test drive, and we couldn’t believe our eyes.
Roger M., Houston, TX

Roger, are you out there???

We'll see.

[choctawmel]

I've had my 'Silver Bullet' for about 55,000 miles now. In '96 it got 4mpg. Has the hole Banks sit up and got 4mpg. Has 4 speed Allison 545 trany, got 4mpg. All the old thing could do, in 1st gear, to climb a mountain, but got 4mpg.
Put EFI on it and I get 5.9 to 6.9mpg. Run the dash air, same thing. Go 75 mph, same thing. Go 55mph, something. Pull the car, same thing. Would love to get 15mpg, but someone would have to fill it up three or four times when I wasn't looking for that to happen.
I've had three gas motor home and they all got from 3.5(that was a 413cid dodge) to 6.9mpg.
If I could get the wife to ride in the toad and keep it floored I'd still get 5.9-6.9mpg.
Before I put the EFI on I tried to find a way to remotely run the toad engine, but that's above my pay bracket.
Maybe GM will offer a package deal someday and we can slide a new Duramax/Allison under our doghouses and just plug it in
mel

[GlenCoombe]

The quote from the folks selling the snake oil....er HFAC Kit came in at just over $1k and I think I'll wait until someone else trys it first.
They guarantee double your milage or your money back.
They don't tell you what the supplimental additives cost though.
I smell snake oil....

[choctawmel]

I installed the 'Turbo City' TBI setup in '04 and all total it cost $1721.42. I did it all myself.
With the toad in tow, I'm right a 19,000 pounds, so 5.9-6.9 is good for a 454. If I had a new Commins and the right gears I would believe 12-15mpg. But a 454? Getting 22? That's snake oil.
Mel
note: I am a produce of a government school, so I may know less then I think.

[ScrapIrony-2]

We have an '89 354, and get right at 5.5, towing a Geo...doesn't seem to make a difference if the tanks are full or dumped...have a carbed 454 and a gear-vendors overdrive that I'm still learning to use...we use the generator a whole lot less since we added 2 kyocera 130 solar panels...doesn't help the mpg though....mike