22? wtf is right!

considering the sticker says 30/33, i'd get yours to the dealer to be checked out. seems like something might be wrong

 

im pretty sure on my auto on a flat road at 80mph im only at 3500 rpms , maybe the stick goes a little higher since its not managed by a computer i dont know

 

i've done 80 - 90 mph for extended periods of time with no problems. but mine is an auto, so the rpm are lower at those speeds. either way i dont think it matters.

 

The stick does go a little higher because it's designed that way so they can get higher gas mileage with the automatic . . . .

 

By that I mean that the final drive ratio is different; it has nothing to do with the computer.

 

I have the MT. Once you get over the inital noise, I think it rolls along nicely on the long highway stretches in Colorado & Utah. And, my mileage doesn't really suffer too much going 80 vs 70+. Still over 30 on the highway.

Incidentally, I found test-driving the Matrix XRS much more nerve wracking than driving the xB on the highway. You really had to wind it up to get the lift benefits going, and it made quite of bit of buzz.

 

I won't speak for anyone else, but the xb feels very, very stable to me at 80 mph. I, too, had to get used to spinning high rpms. But the truth is, most driving is under 60, where this car really shines. Also, it seems like my car has a spot, between 75 and 80, where the engine seems to get quieter, like its sweet spot is right there. At 70, you hear the motor start to scream, and think it will be insane at 80 plus....but mine finds a sweet spot and mellows. I love this car.

 

has nothing to do with being computer controlled or whatever...the reason is because i believe the automatic is a 4 speed automatic and the manual is a 5spd. we have completely different gear ratios, and a different transmission altogether. our final drives are probably way off as well. The ratios are what determines engine rpm vs speed.

 

4000rpm at 80 really isn't so bad.

My '91 MX-5 Miata will hit about 4000 at 60. Though the redline is a bit higher than an xB, it still makes me uneasy when I hit 75.

Luckily I live in Tucson and we don't believe in freeways.

 

The first statement is physics, the second statement is math (multiplication and division), and the last statement was what my speedo and tach said.

 

Tire and wheel size will affect RPM. If you change from stock, your rpm will vary by the ratio of the difference in diameters. My 04 BOP came with the 15" enkei alloys and a 5 speed manual. I drive 40 miles (each way) to work 5 to 6 days per week at 80 - 85 mph. (80moh = exactly 4000 rpm) I have 48,000 miles so far with no problems. If I can keep it below 80, I get between 30 & 31 mpg. At 85, the mpg drops to 28. The axle ratio on the 5 speed is lower than on the auto. Plus the overdirve (5th gear) on the manual is also geared lower than the o.d. on the auto. This accounts for the large difference in rpm, at 80mph, between the manual and auto. This also accounts for the reason that the manaual has more get-up-and-go than the auto.

 

Manual
Ratios

1st 3.545
2nd 1.904
3rd 1.310
4th 0.969
5th 0.815
Reverse 3.250
Differential Ratio 4.312
Combined Final Drive (5th gear) 3.514


Automatic
Ratios

1st 2.847
2nd 1.552
3rd 1.000
4th 0.700
Reverse 2.343
Differential Ratio 4.157
Combined Final Drive (4th gear) 2.910

At any speed, the automatic RPM in 4th gear will be 17% less than the manual in 5th gear.

 

all must also know that most 4-cyl engines have 2+liters. These cars have a 1.5, more motorcycleish. 4,000rpm in our xB's are equivelient to 3,000rpms in 2 ltr cars.

 

The four valve per cylinder engine is designed to run at far higher RPM than a larger standard engine. If the RPMs get over the redline the engine is designed to shut down to protect itself.

 

Alrite now I think I'm really getting screwed. Just picked up an 06' PW XB and it only get 270 on a full tank. Is this correct?

 

[quote="KenzokuXB"]Alrite now I think I'm really getting screwed. Just picked up an 06' PW XB and it only get 270 on a full tank. Is this correct?[/quote

I have never gotten more than 300 on a tank--give it a chance to break in. Auto or Stick?

 

My milage goes up and down, between 260 and 330 miles per tank, depends on how heavy my foot is and whether I am on the interstate or not.

 

My 06 MT sits a little under 4000 at 80, ive had it up to about 115 and no problems, my 91 MR2 was geared about the same, took some getting used to but it doesnt bother me. as for milage, you cant judge it by miles per tank unless you fill it to the same spot every time then drive it until it dies on you. You have to fill it to the same spot ( first time pump kicks off is usually recommended) every time and figure the milage by how much it takes to fill it back to that spot. I usually average a little over 300 miles with a fill of around 9.5 gallons, or around 31-32 mpg.

 

right thanks bro that really explained it. By resistance you probably mean drag, and in that case no, resistance (drag) does not increase with just the square of speed, there are other factors like density and area..and most importantly..drag coeficient. Now who knows the drag coef. of an xB? probably no one, so theres no real way of calculating drag on your car unless you guestimate certain numbers.

Being an engineer myself, i know physics, probably better than most people here. you say resistance is 15% higher at 80mph. 15% higher than what? what are you referencing too? that was my original question to you, although its not really important anymore because it's not true anyway. Decreasing gas mileage with speed such will not be linear so it won't drop at the same rate that you say "resistance" increases

anyways, i wasnt looking for a physics discussion. i simply wanted to know if my engine could handle the load 4000+rpm on a daily basis. I have no experience with toyotas so i don't know if they are notorious for this or not. By the responses so far, it's obvious that this is normal and that the engine can probably take that kind of load for extended periods of time.

thanks guys

 

Thanks so much for all that ratio info; I had been wanting to see it for a long time.