Premium Gas?

[LANDY96]

Well I just got back from my trip to Colorado, from Houston area. On the way up there, I drove mostly on the highway, but there were some off-road driving in between there as well. I was avg. about 17.5 mpg. I did get as bad as 14.5, but I was trodging? through about 6 inches of snow, and ice in New Mexico! WOW that was kinda different. On the way back, I got as good as 20.45mpg, that was from Santa Fe, to Amarillo. I was going about 70mph too. The trip up was about 65mph. After that it was back to about 19mpg. Mind you that was 2 people, and a truck load of gear. I also have a 1.5 inch lift, and 255/70/16 tires. This may also affect my milage. I am not for sure though.

[Gordo T]

Originally Posted by TerryS

Am I the only one that gets annoyed when somone starts their post with "You people in America...." ?

Terry, It's true . . . we do have people in America. Lots of people. As for other parts of the globe, I think they have people there too, although I'm not always sure.

[Chris Hyde]

To the original poster:

Unfortunately 80% of the forum members are grasping when they spout answers as to why you need to run premium fuel in your Rover. If you want the correct answer, pay close attention.

When a company such as Rover creates a vehicle that performs quite sufficiently less than expected from concept, an easy fix is to generally fine tune the engine management to make up for the sloppiness in the valve train, ie: adding aggressive timing tables, causing the need to run a "premium" fuel. When an engines timing is increased and combustion pressure increases, premium fuel burns faster and causes an increase in performance. So in a sense, it is a "bandaid". Unfortunately, it is true, but not a major issue. If more people would study engine development and not simply "slap" together an engine at the manufacturer, you wouldnt have these issues.

Why do you think actual performing cars such as Mustang's, Corvettes, GTO's, etc. dont require the use of "premium" fuel? Its because more R&D went into spec'ing the engines internals. If one of the mentioned was fine tuned from tha factory, it would perform MUCH better than the way it leaves the dealer. How do I know this? Because I use (and have used) several different ECU and tuning softwares that manipulate the ECU from OEM specs and increase performance. You would be really surprised if you knew how much performance is "trapped" into a Mustang when it rolls off the showroom floor. Generally speaking, the new Cobra can simply be tuned from OEM specs and see an increase of 15-25rwhp by adding to the timing tables..........hence the need to run "premium" fuel Hope this helps.

[rov'n]

Originally Posted by IcePick

To the original poster:

Unfortunately 80% of the forum members are grasping when they spout answers as to why you need to run premium fuel in your Rover. If you want the correct answer, pay close attention.

When a company such as Rover creates a vehicle that performs quite sufficiently less than expected from concept, an easy fix is to generally fine tune the engine management to make up for the sloppiness in the valve train, ie: adding aggressive timing tables, causing the need to run a "premium" fuel. When an engines timing is increased and combustion pressure increases, premium fuel burns faster and causes an increase in performance. So in a sense, it is a "bandaid". Unfortunately, it is true, but not a major issue. If more people would study engine development and not simply "slap" together an engine at the manufacturer, you wouldnt have these issues.

Why do you think actual performing cars such as Mustang's, Corvettes, GTO's, etc. dont require the use of "premium" fuel? Its because more R&D went into spec'ing the engines internals. If one of the mentioned was fine tuned from tha factory, it would perform MUCH better than the way it leaves the dealer. How do I know this? Because I use (and have used) several different ECU and tuning softwares that manipulate the ECU from OEM specs and increase performance. You would be really surprised if you knew how much performance is "trapped" into a Mustang when it rolls off the showroom floor. Generally speaking, the new Cobra can simply be tuned from OEM specs and see an increase of 15-25rwhp by adding to the timing tables..........hence the need to run "premium" fuel Hope this helps.

not to rain on your parade but a higher octane gas burns slower...burning faster = hotter = more detonation...higher compression, more timing also contribute to how hot and fast the gasoline burns, to compensate for these factors you need a higher octane gas to burn slower, thus producting less heat...i had a 11 sec mustang that ran like crazy on 87...trick is getting the automobile to that point where its ALMOST going to start detonating on that gasoline, that is where you make the most power...and mustangs gtos and corvettes can run on crappy gas because they have a crappy tune...i dont think landrover said to themselfs that they had a sloppy drivetrain so they needed to tune the motor aggressively...not the case...caddilac for example...they use premium gas, these cars are tuned for optimum efficentcy! not because they are sloppy!

[rov'n]

btw with the cobra, ive had the expierience of working on 3 kenne bell blown cobras...there is many more factors to a cobra than just cranking up the timing on a car that has a blower on it...

[troverman]

My 95 4.0 Range Rover just took it on a trip to White Mountains of NH and it got 18.3 for the whole trip, on Super premium (93) It has only gotten 18.0 mpg 1 time before, usually gets about 16 on road, 14 if mostly in town, when very cold or slippery between 10-12. My 92 Classic (3.9) gets a best of 17.0 and in the very cold slippery conditions it got a worst of 6mpg one week. Nice to have the computer in the P38 do the math for you. That truck uses new Bosch Platinums, a new air cleaner, 38psi rear, 32fronts, new PCV hoses.
LANDY96 you have a 5-speed in your Disco. Obviously this helps your mpg situation over the automatics.
On the K&N discussion I have a K&N on my Classic, it has been on there for 25k miles and never a problem or a Check Engine. It probably gained us 1mpg and 2hp, but every little bit helps. Also use a K&N on my E320 Mercedes, once again no problems. That car gets 26+ on the highway and still has 220bhp.
I was planning on using a K&N in my P38 4.0SE, but after reading the MAF arguments on this forum I went with a stock green Land Rover filter.

All Land Rover V8's should use premium fuel, but not because of most of the above reasons. The V8 was the only RR engine when it came out in 1970, and was used extensively in places where only poor grade gasoline exists. (Africa, etc.) It was actually designed to run on low-grade fuel! You have to keep in mind that the Rover V8 is actually the GM / Chevy "Fireball" 3.5 liter aluminum V8 which was a flop in America because gas was cheap and everyone wanted a Hemi or something of equivelant size. Rover bought the V8, worked it over mainly with oiling system and cooling system changes so it could operate in a Rover, and put it in a few Series III's, then the Range Rover. Since then, the engine has gained fuel injection in 1987, a size increase in 1989 (bore was increased, engine now 3.9L), a size increase for the LSE / LWB models in 92 / 93 (4.2 liters, stroke increase), a significant makeover in 1994 / 95 to the 4.0L model, the stroker 4.6L version, and another makeover with the THOR project in 1999. The Rover V8 has passed out of production now, ending in 2004 or early this year. Most of them are not high compression at all, and even the ones Land Rover dubs as "high compression" are actually not. My '92 3.9 has a compression ratio of 8.13:1. My 95 4.0SE has the "high-compression" version of the 4.0 litre V8, the same one you will find in every Discovery from 1996-2002. The compression ratio is 9.35:1. The 4.6L motor used in Range Rovers (US) 1996-2002, plus the 2003-2004 Disco II also uses this ratio. Anything under 10:1 is low compression, even 10:1 these days is just average. (My E320 is 10:1) The real reason for use of hi-grade gasoline is the catalytic convertor. (s) Low octane fuels will ruin the cats that are used on Land Rovers. Use of lower grade gas will not hurt the engine, even though it is true that the Engine mgt is programmed to optimize the higher octane gas. As for carbon buildup on the valve stems, I know that at least the 4.0 and 4.6 L motors use a "contact" valving system which essentially scrubs carbon off the stem during engine operation.
The price of premium fuel is incredible these days, $2.25 this morning for me.

[cnieri]

Try buying Premium at 2.65 a gallon in California today. Unbelievable!

[troverman]

I am paying $2.30 / gal in NH. To us this is incredibly high. It really is unbelieveable. We conquered Iraq and oil prices are at a record high?!

[LRR219]

I Get About 180-200 Miles To A Tank Of Fuel Driving In The City, Do That Math, Ouch....... From What I Hear The Closer You Keep These Vehicles To 55 Not A Mph Over, You Get The Best Gas Milage Possible, That Being Something To Do With The Shape Of The Trucks Being So Flat In The Rear Anything Over You Are Causing So Much Drag The Gas Milage Plummits, Unfortuanley I Only Drive To Work Every Once In A While So I Dont Really Get To Hit 55, But When I Go Down South On The Highway My Gas Milage Jumps Tremendously @ 55mph, I Know Its Tough To Do But Try And And You Ll See Your Gas Milage Jump! Just My Observation

[Disco1]

Just my 2c worth, did a trip to Alaska, total of around 7000 miles, average 21 mpg on 87 octane. Guess I'm just lucky.

[pieetry]

on gas mileage-

My family has a 2000 rr 4.0 and a 95 disco with a 2000 4.0 engine in it (the 3.9 had a cylinder lining seperate from the block with roughly 167,000 on it, apparently the pervious owner over heated it but never had it checked, put the 4 in used with 40,000ish miles on it less then a year ago) becides that both perty much stock.
On a recent trip to san fransico, roughly 350miles one stop, with the disco fallowing the rr and with both having 4 people plus stuff, the range rover averaged 16.1 mpg and the disco averaged 15.6 both with 89.
The disco is mine so im looking into ways to get it in a bit better shape. Im only learning when it comes to cars so im starting with swtiching out the airfilter so ill see if that makes a diferance. My experiance is that my car runs better on the 91 but i havent noticed a difrence in gas milage.

have fun!

[OrangeCountyLR714]

I used to get 6mpg but that was when i drove my LR like a racecar a lot haha. Now my money is stretched because the 91 premium gas i put in my LR is $2.79 USD a gallon and its going up about 10 cents a week!

I tried what someone suggested in keeping RPM's below 2,000 when accelerating but in california I can't do it, so they end up reaching about 3,000.

When I got my oil change a few weeks ago it was about 200 bucks because the oil was really black and nasty, but I didnt know how to check the oil i thought the car would tell me when i guess, haha, but it didnt. They had to do an oil flush or some sorts and they put in synthetic oil, i guess its the most expensive oil they have, but they told me it was the one that Land Rovers past 2001 needed. Can anyone verify this? Anyways after the flush which was like $99.99 and the new air filter which was about $17.99 and the new oil and what not it was almost 200 bucks!.

Back to Gas mileage, i did get 6mpg but now when i figure it out I get about 10 miles per gallon overall. I go about 45mph driving around town and 80mph on the freeway, 90mph when i can but mostly stay around 80mph.

When I looked at my engine it was crusty with dirt and stuff but i havent gone off roading since the last time i cleaned it i think. But i dont know if its ever been cleaned. HOw much does it cost to get it cleaned? can i clean it or does the dealership clean it? Or can i just wash water on it? will that hurt it?

Thanks for the feedback.

-Jay

[OrangeCountyLR714]

Originally Posted by cnieri

Try buying Premium at 2.65 a gallon in California today. Unbelievable!

Thats cheap =P Im in Orange County and gas today was $2.79

[OrangeCountyLR714]

Originally Posted by LRR219

I Get About 180-200 Miles To A Tank Of Fuel Driving In The City, Do That Math, Ouch.......

yea i usually get about 200 miles to a tank, but one time i did get about 240 yay

[02disco2]

Jay, did you go to Jiffy Lube or something? Sounds like you got screwed out of $200. For the record, the Disco's came equipped with good old regular motor oil, 10w40. (even my service advisor recommended not waiting the 7500 miles between oil changes, should stick to 3-4K) I concur. That is why I do mine between service intervals, and I'd like to punch the engineer that came up with the placement of the oil filter.. friggen thing spills all over the front axel when you take it out.