Forum Discussion
25 Replies
- GjacExplorer III
T18skyguy wrote:
What did you test for with the ram air intake, MPG performance or both?
I installed a Banks system on a motor home with a 460 in it. I did some very careful testing pre and post Banks. Before the Banks I could never break 10 mpg, and this was on a 22 foot mh. With the Banks I got an extra .5 mpg. The real reason for the install was to cure the breaking exhaust bolt problem. The headers are just beautiful, but more noise from both the doghouse and exhaust.The part that's not worth it is the Ram air intake. Again I tested, and found no difference with the stock air intake versus the Ram air. I put the paper filter back in and just as good. The real benefit is in the headers. - anitajeffExplorerMy buddy did the Banks intake and exhaust system on his 2003 V-10. Had a put a the dyno-meter before and after. He got HALF of what Banks said he would. Lots of money and time for half the power. Not worth it IMO.
I did 5-Star Tuning for 87 octane. Easy cheaper...works!!! - T18skyguyExplorerI installed a Banks system on a motor home with a 460 in it. I did some very careful testing pre and post Banks. Before the Banks I could never break 10 mpg, and this was on a 22 foot mh. With the Banks I got an extra .5 mpg. The real reason for the install was to cure the breaking exhaust bolt problem. The headers are just beautiful, but more noise from both the doghouse and exhaust.The part that's not worth it is the Ram air intake. Again I tested, and found no difference with the stock air intake versus the Ram air. I put the paper filter back in and just as good. The real benefit is in the headers.
- Chum_leeExplorer
timmac wrote:
the BSFC is not so accurate anymore with the new motors and better computers on board to control fuel burn, we have more HP/Torque on some of the same size motors than we did 20 plus years ago with better fuel mileage.
A good example is a old Ford 460 cubic inch 35 foot motorhome from the early 90's that weights around 18,000 lbs gets about the same MPG as a newer Ford V-10 415 cubic inch 35 motorhome that weights 21,000 lbs.
So why does a heavier motorhome of today gets the same or sometimes better MPG with a smaller motor with more HP/Torque than one 25 years ago ?
Huh? Well of course! Newer heavier motorhomes often get the same or better mileage with smaller engines than those of yesteryear because the BSFC (which you say is no longer accurate) spec's are better due to improved engine/transmission design at the factory. Please read up on BSFC. It is a timeless measure of engine fuel efficiency that is more pertinent today than ever. Newer transmissions also have more forward/overdrive gears than previously which also helps fuel mileage.
Again, generally, fuel mileage is not measured at max. rated power/torque so your point about HP/Torque is not relevant to this discussion on fuel mileage which as far as I'm concerned . . . . is over.
Chum lee - timmacExplorerWhen you can increase more torque on a motor in the lower RPM range you can get up a large hill while working the motor less, less RPM's and a lower gear in some conditions, also the motorhome can gain speed faster and easier with more torque and HP, if one does not drive it like a race car you could get some better mpg.
Also remapping the computers to make the motor burn fuel better and shift better like 5 Star Tunning does also helps.
Also the BSFC is not so accurate anymore with the new motors and better computers on board to control fuel burn, we have more HP/Torque on some of the same size motors than we did 20 plus years ago with better fuel mileage.
A good example is a old Ford 460 cubic inch 35 foot motorhome from the early 90's that weights around 18,000 lbs gets about the same MPG as a newer Ford V-10 415 cubic inch 35 motorhome that weights 21,000 lbs.
So why does a heavier motorhome of today gets the same or sometimes better MPG with a smaller motor with more HP/Torque than one 25 years ago ? - Chum_leeExplorer
timmac wrote:
Chum lee wrote:
Simple gasoline engine air/fuel stoichiometry says you need 14.7 lbs of air to 1 lb. of fuel. If you add more air, then you need to add more fuel or you will generate a lean condition which will raise exhaust gas temperatures and eventually cause engine damage. If you add more fuel than necessary, then you generate a rich condition which wastes fuel and reduces mileage. Engineers/chemists know this. I guess the rules of mathematics and chemistry don't apply to everyone else.
Chum lee
Yes that is true on the surface but more HP and Torque also means the motor works less to get up that big hill when we are talking about a 20,000 lb motorhome, so there can be gas savings in certain times with the Banks Power Pack System..
I don't understand the above statement. With a given gas engine (Banks modified or not) a given motorhome, and a given hill, it will take the same HP to go up the same hill at the same speed. If the Banks system squeezes out a few more HP in a given RPM range, to maintain constant speed, the driver will close the throttle to compensate for the increased HP at that RPM. Yes, no? A difference could possibly be that the engine now makes sufficient HP at a lower RPM to go up the given hill in the next higher (numerically lower) gear. That could save fuel due to lower RPM's, higher manifold pressure, and, less intake pumping loss. Yes, no? Fuel mileage is usually maximum at/close to the most economical driving speed which is usually just slightly above the point where the transmission shifts into its highest gear. But, for obvious practical reasons in a Class A gas MH, it's usually figured between 55 and 62 MPH. Above 62 MPH air resistance starts to increase drag substantially reducing MPG. Below 55 MPH, IMO is unsafe to drive on most major highways. Many people seem to get lost with the idea that MPG is never calculated at maximum power. Search BSFC: Brake Specific Fuel Consumption for more understanding. BSFC is the amount of fuel in lbs. that a specific engine burns at a specific power setting per hour per HP produced. It is very well understood by engine designers but not by the general public.
Chum lee - timmacExplorer
Chum lee wrote:
Simple gasoline engine air/fuel stoichiometry says you need 14.7 lbs of air to 1 lb. of fuel. If you add more air, then you need to add more fuel or you will generate a lean condition which will raise exhaust gas temperatures and eventually cause engine damage. If you add more fuel than necessary, then you generate a rich condition which wastes fuel and reduces mileage. Engineers/chemists know this. I guess the rules of mathematics and chemistry don't apply to everyone else.
Chum lee
Yes that is true on the surface but more HP and Torque also means the motor works less to get up that big hill when we are talking about a 20,000 lb motorhome, so there can be gas savings in certain times with the Banks Power Pack System.. - wolfe10Explorer
Chum lee wrote:
Simple gasoline engine air/fuel stoichiometry says you need 14.7 lbs of air to 1 lb. of fuel. If you add more air, then you need to add more fuel or you will generate a lean condition which will raise exhaust gas temperatures and eventually cause engine damage. If you add more fuel than necessary, then you generate a rich condition which wastes fuel and reduces mileage. Engineers/chemists know this. I guess the rules of mathematics and chemistry don't apply to everyone else.
Chum lee
Agree, this is just the basic equation. BUT (large BUT)there are several significant variables that balance EMISSIONS, ENGINE LONGEVITY, POWER AND ECONOMY.
Engine timing, and on today's engines valve timing as well as EGR can all be juggled to accentuate one over the other(s). - Chum_leeExplorerSimple gasoline engine air/fuel stoichiometry says you need 14.7 lbs of air to 1 lb. of fuel. If you add more air, then you need to add more fuel or you will generate a lean condition which will raise exhaust gas temperatures and eventually cause engine damage. If you add more fuel than necessary, then you generate a rich condition which wastes fuel and reduces mileage. Engineers/chemists know this. I guess the rules of mathematics and chemistry don't apply to everyone else.
Chum lee - usersmanualExplorer
Tom/Barb wrote:
usersmanual wrote:
I got 7.5-8 before and after system
We have averaged 9.7 MPG over 50,000 miles (gallons bought over miles driven) that includes the gen-set usage. (Not much)
It's my opinion it's due to the banks system.
that's great Mine was 8 max but all in the western states so more mountains etc banks made zero difference except great power increase
when you run the boost at 36-38 and give er hell it has to burn more fuel otherwise you would not get the 100 HP increase
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