Gas Mileage: 454

[legomybago]

If your getting 12 mpg Rick, I wouldnt touch that motor W%

[eXodus]

so the K&N starts doing it's wonder:


8.65 MPG

Just kidding, was driving without the horse trailer - but much faster 65 mph.

[stopngo]

We have a 37 ft. Elanden with the 454 and have never gotten more than 6 mpg, 5 mpg is the standard, this is just a fact I have had to accept. After numerous trips, short, long, flat, mid summer, winter, regardless the mpg never varies much above 5 mpg. I once discovered a fuel leak at the fuel pump and just knew my mileage was going to double, no dice, apparently it only leaked while ideling, I guess at speed the fuel demand from the engine drew the fuel up the line so very little actually was lost. I have never weighed the rig, but we never carry fresh water, or full holding tanks, tire pressure is always monitored, clean air filter, oil changed regularly etc. It just is what it is 5 mpg, thankfully gas is not 4 bucks a gallon anymore.
Rick aka 89Elanden

Thanks for the honesty

Our 32 ft Elandan gets 6.5 mpg (and only because it is 5 ft shorter)  Head wind..... Tail Wind .....55....65....75...up hill .....downhill its always the same. With a low geared rear end ratio you can drive any way you like........you cannot change the MPG. I disagree with the notion that driving habits make a difference.

[stopngo]

Ohh by the way just for the purpose of full disclosure........the 6.5 was on the US Gallon. On the Canuck gallon which is 160 oz to the US 128 I get 8

[eXodus]

since I'm from europe I grow up with how many lites per 100km.
miles per gallon makes it hard to compare since its a equation which goes to indefinitely around zero.


6 mpg equal 39L (11 gallons) per 100km (70 miles)
7 mpg equal 33L per 100km
8 mpg  28L
9 mpg 25L
.
.
14 mpg 15L
.
.
24 mpg 10L


we got on 5000 miles with our 18 ft Horsetrailer about 7.5 miles a Gallon with 19000  lbs total on the scale. I did open up the factory cold Air intake and installed a K&N airfilter. Plus good spark Plugs and 8mm silicon cable.
Fres Oil every 4000 miles.

[eXodus]

the only Motorhome in Europe I have driven was a Class C Type and it needed about 14mpg  15L/100km and we could drive this thing with 100 mph !
For Europe it was huge... here It would be not even a Mini Winnie   Over there I would need a Semi/Commercial drivers license to drive a MH big as they are here.

[stopngo]

Just returned from a 3000 mile round trip after having Head Gaskets and Waterpump replaced. Best Gas mileage I have ever had. Between 7.5 and 8 .....8 on the flats.1985 32 ft Elandan.

[tiinytina]

about normal.. 7.4 is my average.... Banks, no AIR, full tune up.  28ft. about 14K loaded with empty waste tanks and 10gal FW.  60+ gal fuel in 80 gal tank.

[tmsnyder]

I'm tracking the mpg's for my 31' HRC Aluma-Lite XL here: 


http://www.fuelly.com/car/chevrolet/p30/1990/tmsnyder/454843


This is a 1989 454 with two air pumps removed, distributor re-curved, exhaust flow restrictions removed, Edelbrock 1406 carburetor.

[coltronicola]

With my RV and trailer boat with gas 8.5 mpg and with LPG 7.8 mpg, in Italy gas = 1,5 â,¬/litro and LPG = â,¬ 0,5 â,¬/litro

[tmsnyder]

With my RV and trailer boat with gas 8,5 mpg and with LPG 7,8 mpg, in Italy gas = 1,5 â,¬/litro and LPG = â,¬ 0,5 â,¬/litro

How many liters are in your gallon in Italy?

[coltronicola]

hi Tmsynder, 1 litro = 0,26 gallon

[Turbodime]

'89 HR and we have put 10,000 miles on it since the 2.5yrs of owning it.  It has a total of 35,000 miles on it and still has the AIR system.  I've rebuilt the carb, new wires and plugs. 

We have 6 kids and tow a 4 X 10 trailer for 5k of those miles.  Spent two months and 15 states living out of it and have documented every gallon of fuel used.   

Highest 8.6mpg
Lowest. 5.3mpg
Average 6.8mpg


I drive around 65-70mph wife does 55-65mph. 

[tiinytina]

yup.. highest was 10.1 I think (downhill in a hurricane) LOL... difference between how its parked when filled up and who does the filling....
lowest 3.2... freezing conditions with snow had put a naked KN filter assembly on with no exhaust recycle to carb.. iced up....

Average... KN, no AIR, edelbrock quad, Magnaflows 2.5" dual, silicone racing wires, new cap/rotor, 2 ignition control modules, 7.2mpg avg.. no toad, kids have fur about 300+lb of them on board every trip.  88K or so on the ODO now.  10 yrs of mileage data every gallon in calculated, bought it with about 67K on it.   MD, VA, DE, NC, PA, OH is the limit of where we have taken her.... 

AVG is 6.6 over the appalachians MD to Breezewood but 7.6 from there to OH... and 7.4 haul back... 

[tmsnyder]

It would be interesting to see others log their fuel mileage on fuelly.com as I did above.   That way we can see all the data.


Fill ups are super easy, just one text into fuelly and it updates the logs.

[DRMousseau]

Thought I'd look into this topic again,... but it's been rather quiet.

I do keep full 100% records of fuel and mileage. And for last 4000mi of this year in Cruise Air II,... a high of 6.6mpg and a low of 5.6mpg. those extremes are of long durations of relative speed. Lower speeds of duration,... higher mileage.

Now,... the trends I see myself, here among others, and those elsewhere.

The greatest influence in mileage, is SPEED! Seems nothing affects your mileage more,... the frontal load of wind may vary a bit among styles, but speed increases the frontal load inversely for everyone. Seems the variations of frontal designs have only a small effect on mileage. And EVERYONE has a similar drag since there's very little variation here. How much drag??? Enough to easily suck up a small car right up to your rear bumper!!! And the same power is holding ya back as speed increases. The combined load of wind resistance and drag can easily exceed the vehicle weight. Short light "boxes" see little difference if any, from longer heavier "boxes". It really doesn't take much to get an RV rollin',... a couple strong backs can push 'em a few feet in neutral regardless of size. But at speed,... your engine is gonna work hard and eat fuel!!!

Biggest improvement for mileage? Newer computerized fuel injection systems! More than any other modification of gear ratios, exhausts, intakes, trans, overdrives, or anything else.... seems obvious that those with fuel injection can see an EASY 10-20% or even greater improvement of mileage over an identical carbureted model with an unskilled pedal-pusher. NOW,... many mods will significantly affect and generally improve POWER, but it takes the same amount of power to move your RV against the resistances encountered. And that means no real improvement in mileage. A 700hp engine will require less pedal effort and can attain a higher speed against load resistances,... but mileage at a set given speed will still be the same as an OEM stock model. Drive at 7mph for an hour, and most will use about a gallon of fuel (unless your AC is on for that hour,.. then you'll use another gal!). Tow the same with your 20hp garden tractor for 7mi,... and you might be surprised to see the same mileage!!!

And diesel vs. gasoline,.... that's apples n' oranges!!!! The available energy in a gallon of each is significantly different, but it still takes the same energy to move a given load. Per gal,... diesel has a lot more, and you'll generally see a greater mpg.

Oh,.... and a good tune-up, can significantly affect mileage. Ya got a plug fouled and missing,... then the fuel mix running thru that cylinder is doing nothing but creating an added load. Subtract the mileage it was capable of.

Anyone see differently? How many see a difference depending on WHO's driving??? Lol!!!

[lexadmn]

We completed a 1100 mile round weekend trip and as I stopped for gas, I calculated mileage as I had never done this before. Were driving a 1994 Winnebago Warrior 25' with the 454 and 4l80E
At roughly 12,000 pounds or a little more, and mostly flat terrain at 70 mph, I averaged 10.51 mpg.
At 60 mph and hilly terrain (rolling hills South of Rolla, MO - not mountains), I averaged 9.31 mpg.
Lastly, at 75 mph and mostly flat terrain I averaged 9.56 mpg.

KC

[Froggy1936]

What type of Fuel injection do you have And what is the RPM @ ea of those speeds ?  That is pretty fantastic MPG  Frank

[Winnebago Warrior 94]

We completed a 1100 mile round weekend trip and as I stopped for gas, I calculated mileage as I had never done this before. Were driving a 1994 Winnebago Warrior 25' with the 454 and 4l80E
At roughly 12,000 pounds or a little more, and mostly flat terrain at 70 mph, I averaged 10.51 mpg.
At 60 mph and hilly terrain (rolling hills South of Rolla, MO - not mountains), I averaged 9.31 mpg.
Lastly, at 75 mph and mostly flat terrain I averaged 9.56 mpg.

KC

I have a 1994 winnebago  warrior   22 foot 454 engine ..is your engine fuel injected ? I wonder what type of gas mileage   I will get

[lexadmn]

Yes, the 454 is injected, just a throttle body with no smog.
I use the cheapest fuel I can find - 87 octane. I am not loyal to any fuel company, just what is available - Pilot, Flying-J, BP, etc., whatever is close to the Interstate.
No idea of the rpms, I have never done the math. I do know I have 4.31 gears, 16" wheels with P235 tires.

[Rickf1985]

4.30:1 is a ratio I have not heard much of. 4.11, 4.27, 4.56, 4.88. are the most common gearing's. 4.27 was used mostly in older Jeeps.

I guess the 4.30 is something they are using to match up with the overdrive transmissions and apparently it is working. That is some good mileage figures for 12,000 lbs. and at those speeds.

[Winnebago Warrior 94]

We was told it was fuel injected ..but my husband said it looks like a carburetor . .is there a carburetor  and fuel injected   ? Somewhere we saw where it said it is a 93 chevy but somehow the body is a 94 so not sure what that classifies it as ..lol so all 454 chevy chasing are fuel injected or just certain ones

[DRMousseau]

We completed a 1100 mile round weekend trip and as I stopped for gas, I calculated mileage as I had never done this before. Were driving a 1994 Winnebago Warrior 25' with the 454 and 4l80E
At roughly 12,000 pounds or a little more, and mostly flat terrain at 70 mph, I averaged 10.51 mpg.
At 60 mph and hilly terrain (rolling hills South of Rolla, MO - not mountains), I averaged 9.31 mpg.
Lastly, at 75 mph and mostly flat terrain I averaged 9.56 mpg.

KC

This is GREAT!!!!
Your figures clearly show the importance of speed,... jus 5mph can mean a difference of 10% in mileage. At higher speed, drag is HUGELY significant, and jus can't be overcome or effectively reduced.


And you gave good figures for others to compare in regards to fuel injection, given a similar engine, vehicle size and weight.


If I were to have guessed,... I would have expected you would have about a 20-30% improvement over what get, all considered, and would have estimated 7-8.5mpg. Your mileage is GREAT and slightly better than I would expect, especially at speed.

[lexadmn]

We was told it was fuel injected ..but my husband said it looks like a carburetor . .is there a carburetor  and fuel next ? Somewhere we saw where it said it is a 93 chevy but somehow the body is a 94 so not sure what that classifies it as ..lol so all 454 chevy chasing are fuel injected or just certain ones

Our chassis is a 93 as well and the coach is a 94 (like yours) and it is fuel injected. As DaveVA78Chieftain posted, I suppose the throttle body could be mistaken as a carburetor to someone that is not at all familiar between the two.
I posted a pic (above) that shows what the fuel injection throttle body would look like.

KC

[bluebird]

Actually my Challenger with the throttle body injection did better on fuel than the Daybreak with port injection. It also had more pep from a stop sign, not that I pushed them much. I would have thought just the opposite looking at the body shape. The Daybreak sat lower to the ground and had the slanted nose, so I thought that it would have cut the air better. The Challenger had 35,000 less miles on it too.