8.1 mileage improvement?

[woodyk]

I've been reading about allot of fuel mileage improvements on the 8.1 from Omey's and also from installing Taylor wires. My question is how much of an improvement do you get with these DYI mods? I know if I keep my foot ourt of the throttle body and keep the RPM around 2100 theat seems to get me the best mileage, around 7 mpg, wither I'm towing my toad or not. I'd love to see 8 and higher if possible. So with all the expertise out there what do you all say????? Get a mod or keep my foot out of the throttle body?

WoodyK
2004 Allegro Bay DQ

[TandW]

Three tips. Tire air pressure should be monitorred constantly and should be kept at the higher end of what is recommended for your gross weight. An attempt should be made to have the chassis higher in the back as it goes down the road. Two or three inches is enough to effect the classic wedge shape which will aid in engine cooling and tail end drag. The main belt driven engine fan should almost never have to run if the bulkhead surrounding the cool-pack or radiator is entirely uncompromised. No air should pass thru this bulkhead unless it goes thru the cool-pack. Good luck!!!

[Max Hubrich]

I get 8.3 to 8.5 mpg towing a 3400# toad with the rig at full weight--22,000. I carry plenty of fresh water, and usually a full tank of fuel. I just averaged 8.4 from Maine to Gulfport MS (1800+ mile trip). I find I do better with manual throttle (gas pedal) control. The cruise control is just too busy trying to maintain speed up all hills, overpasses, etc trying to keep me up with the diesels --- Just too many downshifts for me.

You'll love the UP (Ultra Power) upgrade. I also put in the CAI (cold air intake) and of course, the Taylor wires, with heat sleeves and the colder spark plugs.

Good luck,

[woodyk]

Thanks Tand W,

I've learned along time ago when I had my first RV tire blow out on I-65 south out of Nashville on Thanksgiving weekend, an old crusty guy finally arrived and stated harshly--let me guess it's and inside tire and it's a michelin and you have the extension valves reveted to your hubcaps? Yes to all three- anyway after he started working and of course I helped to get him to cool down He stated you never really know your grossweight all the time so you should always run your tires at max cold pressure. I've done that ever since and when my michelins got to 7 years I purchased a set of Toyos M54 e-balanced--registered them and I've been a happy camper ever since. How much does the UP cost?

[Max Hubrich]

The cost of the UP upgrade depends on what you do yourself. You can remove the computer and send it to Oemy or Brazels and have them do the computer upgrade and you can do the CAI and the wires, plugs,etc yourself.

Contact Oemy or Brazels for what you want done by them. They will send you all the parts and pieces if that is what you want to do.

[wa7hra]

My 2003 Dolphin just finished it's 14th trip to/from the rain forests of Western Washington and the desert of Southwest Arizona. It now has 38,000 miles on it. The scale weight for the loaded motorhome and towed vehicle is 24,500 pounds. In additions to performing the required maintenance as defined in the WH owner's manual, I maintain the Michelin recommeded tire pressure. I generally buy gas at the same stops, so I have a pretty good idea of how much fuel I use. I also raise the rear of the MH with the rear leveling jacks in order to eliminate the bubble in the tank and filler neck so that I know the tank is full. As for MH modifications, the only change has been the Ultrapower ECM reprograming.

Now,this may be offensive to some people, but I have found the secret to good gas mileage is to observe the SPEED LIMIT. For vehicles with a tow, it is 60 mph in Washington and 55 mph in Oregon and California. It pays off at the gas pump.

I had a good trip down this year. Temperatures were moderate and there was very little wind. The first leg of the trip was from my home in Hoodsport, WA (on Hwy 101 north of Olympia) to Corning, CA on I-5. Much of this part of the trip is serious mountain driving. It is a 639 mile drive with an overnight in Sutherlin, OR and Redding, CA. I regularly drive the 639 miles on a single tank of gas. I am guessing that my "75" gallon tank actually holds about 80 gallons. This year I used 73.4 gallons which works out to 8.71 mpg.

The second leg from Corning to Bakersfied, CA with overnights in Lodi and Visalia was 392 miles and used 40.4 gallons which is 9.69 mpg. This is mostly level driving through the Sacramento and San Joaquin Valleys.

The third leg from Bakersfied to Quartzsite,AZ was 408 miles and required 47.2 gallons which works out to 8.64 mpg. This part of the trip takes us up Tehachapi Pass and across the high desert of CA. with an overnight in Hesperia, CA.

Average gas mileage for the trip of 1437 miles was 8.92 mpg. This certainly wouldn't be great mileage for a car but it's damn good for a house.

Bob, wa7hra

PS: I have never had a brake problem.

[DriVer]

Quote:

Originally Posted by wa7hra Average gas mileage for the trip of 1437 miles was 8.92 mpg. This certainly wouldn't be great mileage for a car but it's damn good for a house.

Ya done good! I also try to limit myself to the speed limit however when it gets to be 70MPH I sorta want to back it down a bit!

Basically I like 2100-2200 RPM. That's where the power band lives on the engine.

[Gary - K7GLD]

Quote:

Originally Posted by DriVer Ya done good! I also try to limit myself to the speed limit however when it gets to be 70MPH I sorta want to back it down a bit! Basically I like 2100-2200 RPM. That's where the power band lives on the engine.

I hope that general rule also applies to the GM 454 gasser in our recently acquired '88 Winnebago - we see somewhere a bit over 2000 RPM at about 55 MPH - using the plain old GM TH400 tranny. In a 100 mile round trip to our favorite fishing/camping spot - involving a 5000+ foot mountain pass and about 40 miles of steep grades, we get a bit over 7 MPG - dunno if we'll EVER see enough flatland RV travel to see what it will do under more favorable conditions...

[bdaball]

I picked up almost 1 mpg when I switched to a Synthetic engine oil. I'll just say 5-30W to prevent an argument on which brand is better.

[bdaball]

Quote:

Originally Posted by Max Hubrich I get 8.3 to 8.5 mpg towing a 3400# toad with the rig at full weight--22,000. I carry plenty of fresh water, and usually a full tank of fuel. I just averaged 8.4 from Maine to Gulfport MS (1800+ mile trip). I find I do better with manual throttle (gas pedal) control. The cruise control is just too busy trying to maintain speed up all hills, overpasses, etc trying to keep me up with the diesels --- Just too many downshifts for me. You'll love the UP (Ultra Power) upgrade. I also put in the CAI (cold air intake) and of course, the Taylor wires, with heat sleeves and the colder spark plugs. Good luck,

Hey Max,
Did you mis the turn for NC?

[wa7hra]

Quote:

Originally Posted by DriVer Ya done good! I also try to limit myself to the speed limit however when it gets to be 70MPH I sorta want to back it down a bit! Basically I like 2100-2200 RPM. That's where the power band lives on the engine.

The problem with driving a motorhome with a nose cone like a barn door is wind resistance. The faster you go, the more pressure you gain. It can't be good for fuel economy.

Bob, wa7hra

[DriVer]

Quote:

Originally Posted by wa7hra The problem with driving a motorhome with a nose cone like a barn door is wind resistance. The faster you go, the more pressure you gain.

Bob, wa7hra, That's right if you look on a graphic, the wind resistance increases almost as fast as an F-16 can climb.

For you old timers that would be an "F8F!"

[max49]

quote "It is a 639 mile drive with an overnight in Sutherlin, OR and Redding, CA. I regularly drive the 639 miles on a single tank of gas."

It's not my business but don't take this wrong, but replacing the fuel pump is probably close to $1000. I've replaced 1 on my WH under warranty and paid for one on myold Ford MH .The fuel keeps the fuel pump cool , hopefully making it last longer. Since then, I don't think I've let the gauge below 1/2.

I know , I may be the only one who believes this but in CO, the speed limit is 75. If there no wind or a favorable breeze my 18,000 lb rig plus a 2,000 lb+ trailer will cruise the speed limit , + sometimes and it is happy. The gas mileage is just as good for sure and according to the Actia IP is even better than at 60 MPH.



My true average is between 8.5 and 10

[Gary - K7GLD]

Quote:

Originally Posted by bdaball I picked up almost 1 mpg when I switched to a Synthetic engine oil. I'll just say 5-30W to prevent an argument on which brand is better.

AH, too chicken to use the "A" word, eh?