ohhsoo

two completely different topics

first one is i read the articles abt ppl not getting any better mileage from higher octane and instead of just taking everyone's word and being as stubborn as i am i decided to fill up on 87 and 93 and after 2 full tanks of each ive drawn a conclusion...mabe i have a special miracle car but on 87 octane driving the same as i did when i filled it with 93 on a full tank i would get 200 miles out od my tank...mabe 210 b4 i had to avoid hills cuz my car was running out of gas and would sputter lol

on 93 octane both times my car wen 260+ miles....the first time was like 262 and the second time was almost 270...so i personally saw a huge difference...

BUT!!! the main reason im posting is this...my driver seat is annoying the S#!+ out of me...when i take a turn or hit a hill it clicks do to the added pressure on it i guess and i cant stand it....is there any seats tht would swap in so i can keep the electric tilting and moving functions...prefferably something a little sportier looking instead of just replacing them with the same ones...or any aftermarket ones tht have tht option that anyone knows of....i read an article where someone used the stock framing of the seats and electric motors but switched out the cushions and back support for a racing one...im looking into tht but b4 i start cutting seats apart im hoping for other options...please and thank u.

ohhsoo

Nobody has any input at all?

285exp

Apparently you have a miracle car. 200 miles to the tank means you're getting around 12 mpg, about what I average in my V10 F250 pickup. Then you say you're getting 30% better mileage simply from switching to premium, but you're still only getting around 17 mpg. The worst mileage I've ever gotten from a tank in my 97 ES300 was 16 mpg, and my typical average for city/hwy mixed driving is 20 mpg, all on regular. Let's just say that either there's something very badly wrong with your car or you're just making stuff up.

Putting racing seats on your stock power seats is not very feasible. I suggest earplugs.

mkeeney

I'm not even going to address your MPG claims. Your test was not valid in the least bit.

285exp

As a public service to the fine members of this site, I'm going to conduct a comparison of regular vs premium. This will neither prove nor disprove conclusively whether one is better than the other for all vehicles in all conditions, just whether or not it has any discernable effect on my 1997 ES300. It will not be a blind test, as I know what fuel I will be putting in. It will not be possible to drive exactly the same way with the exactly the same mix of hwy/city driving, though I will try very hard to do so. I will not be judging subjective criteria like engine smoothness or throttle response, or whether or not my baby deserves premium fuel because it's a Lexus, the only thing I will be concerned about is mpg and cost per mile. I am very satisfied with the smoothness of the engine and the throttle response, and I've never had any audible knock while using regular, so I expect no knock from using premium. I've never had to replace a knock sensor, so I am unconcerned about regular being harmful to them either. I am cheap, and therefore if it turns out that any increase in mpg more than offsets the extra cost of the fuel, I will gladly admit it and start using premium.

I bought the car new, and it currently has around 168k miles on it. It has been serviced regularly, and the current service is up to date. I have been keeping a spreadsheet detailing every gallon and every mile and the average mpg of every tank of fuel I have put in the car for the past two years. I use the car primarily for commuting to work, and I drive pretty much the same route at the same time of day. Overall, the car has gotten 21.3 mpg over the past 2 years and @16k miles. If you exclude the few long highway trips, it has gotten right at 20 mpg. In order to try to cancel out any environmental factors like ambient temperature and changeover from winter to summer blend fuel, I am going to compare this years mpg from the same time periods in 2011 and 2012. I still have about a half a tank of regular in the car, and by the end of next week I should have burned it down far enough to start the comparison. I'll use premium for the next 4 tanks of fuel, driving my usual route.

Historical data:

2011
Date Miles Gal MPG
3/14 250.7 13.7 18.3
3/29 290.7 13.4 21.7
4/19 249.4 13.1 19.0
4/29 222.7 10.8 20.6
Total 1,013.5 51.0 19.9
2012
Date Miles Gal MPG
3/20 281.5 14.3 19.7
4/5 286.0 14.8 19.3
4/19 294.2 13.8 21.3
4/30 286.4 14.0 20.5
Total 1,148.1 56.9 20.2

Combined, the average mpg for the comparison period is 20 mpg. Currently, premium around here costs about 8% more than regular, so at current prices I will need to average 21.6 mpg in order to break even, and any more than that will be money in the bank.

285exp

First couple of tanks of premium are in the books. The last 4 tanks of regular before switching to premium were:

Date Miles Gal MPG
1/9 287.1 13.7 21.0
1/28 312.4 14.5 21.5
2/15 275.8 14.2 19.4
3/11 313.0 14.9 21.0
Ttl 1188.3 57.3 20.7

There was another refill on 2/27, but that tank was almost entirely highway, so I disregarded it because it would distort the average.

The last two tanks were premium:

Date Miles Gal MPG
3/25 312.2 14.3 21.8
4/10 308.2 14.7 20.9
Ttl 620.4 29.0 21.4

285exp

Finished the fourth tank of premium:

Date Miles Gal MPG
4/22 293.3 13.8 21.2
5/9 301.8 14.6 20.7
Total 1,215.5 57.4 21.2

The average over the test period was 21.2 mpg on premium vs the average for the previous 4 tanks of regular of 20.7 mpg, an increase of .5 mpg, or a little over 2%, pretty much within the margin of error. If we go back to the same time periods for the previous two years, where the average was 20 mpg, the increase is about 6%. Either way, any increase in mileage was less than the increase in fuel cost. So, for my vehicle and the way I drive, I'll save a little money and go back to regular.