Say you're making a turn onto a long, straight street, or stretch of road. The closest car ahead of you is quite a distance away. So, you push the pedal to the floor, and reach higher RPMs (example: 5000), then let go of the accelerator after you reach 45mph, or so. Keep in mind, this would be if you have an automatic, which I do. Would this hurt the tranny, or anything else at all? The reason I ask this is because I did this on the way home from work. Once I got up to like 4800 RPM, I felt a sudden tilt, or shake in the car. Hopefully, that was nothing serious. But it could have been that treacherous black ice. I hate that stuff.

 

should be fine, i mean, alot of people who drive manuals dont even switch into there next gear until there up to 5.5k 6.5k

-Jon

 

Okay. Thanks a lot.

 

....i should add while some people do that, they are retards, and are putting far too much wear on their engine. Accords dont have DOHC VTEC, once you use your peak torque, change gears and stop revving your engine.

 

But would if be okay if I do it very rarely?

 

RPM stands for Ruins Peoples Motors. higher RPMs create more wear and tear on your motor. drive around all day at 5k RPM and you will shorten it's life. hit it once and a while and it's not that big a deal.

 

LOL

'Ruins Peoples Motors'

so you are going to put-put-put along a under 2500???? LMAO

wear and tear is a part of life and operation on any ICE much less any piece of machinery, accept it, move along, and have you merrie way of winding out the gears,

If you are so stuck on having your car last forever and ever and never want to tear it down, put your car back to stock and drive like grandma

personally i like to enjoy my ride and dont mind tearing down and rebuilding every 50k or so

life is too short to be driving around with a stick up your ***

 

Oh don't worry, I ruin my motor on a regular basis

but to be fair, he asked if it was bad to do, and I told him.

 

 

jweller:

You've been reading from "the old one" eh?

 

My accord makes peak tourqe at 4500 rpm. I run it up higher than that every day that I drive it.

 

ya, from what i see on dyno runs people post accord f22's seem to be peaking anywhere from 4-5k for torque and a little over 5k for hp.

i notice that on my car it pulls hardest between 5-6k, if i go past 6 it doesn't seem to pull as hard so i usually shift at around 5800 if i'm getting on it. that seems to be about the right spot for me.
i see it pointless to pull it much past your peak horsepower because the power starts to go back down. just my opinion

 

RARELY does shifting at peak HP or Torque produce the best acceleration #s.

Lets say for example an F22 produces these numbers (whp) on a dyno in [I}2nd[/I] gear, a gear we all like to abuse:

3500rpm 86
3750rpm 92
4000rpm 106
4250rpm 110
4500rpm 115
5000rpm 124
5250rpm 129
5500rpm 133
5800rpm 139
6000rpm 133
6250rpm 115

Shifting at 6250 would drop you down to 4200rpm roughly and shifting at 5800, the hp peak, would drop you to about 3800 and in a weaker part of the powerband to accelerate in 3rd gear. Read: area under the curve

See my point?

Here is some math. Shifting at 6250 which drops you to 4250 gives you a total of 998total whp by adding the whp from each interval measured divided by the 8 rpm intervals = 124whp on average while accelerating. Shifitng at 5800 would drop you to about 3600 (gear ratios and at what RPM point they land you in after a shift is dynamic and is relative to what RPM you shift at) and would result in the following: 1034 total whp and 9 rpm intervals and an average whp of 114 while accelerating.


It may be better to shift at redline even though you are losing whp than to shift early and drop into an even weaker part of the power band than it would be to wind out 2nd gear. Time on a dyno can help you realize ideal shift points.


These are not actually dyno numbers from a real F22, but are probably close to reality. I did not include torque numbers because HP is a function of torque. This wasnt a post directed to anyone in particular, it is just a hypothetical example to illustrate my point. I could and very well may be wrong with an F22. But the concept is always correct, do your respective math, happy holidays and happy tuning.

 

ya, i thought about that also, cause i noticed that the rpms drop lower than i want when i shift, but for me, i'd rather go easier on the motor and lose a little like that then to rev my motor to redline. i guess if i was at the track i'd probably rev it because of what nick said. that makes a great point and i see the math behind it.

 

yeah reving to redline will not give you more power, as someone said before...max hp comes in at 5500 rpm on the f22b1, no point in going up to 6250. btw, its a good idea to rev it up a little maybe once every 2 days to clear up carbon buildup. its like exercise for your car, if you never run fast and one day you are being chased by a dog, you will see what happens. as long as you're under redline, you're ok and its normal engine operating range. the only bad thing about revving it up all the time is that you'll burn more gasoline and burn oil quicker...just never go over redline unless you got reinforced internals.

 

"yeah reving to redline will not give you more power, as someone said
before...max hp comes in at 5500 rpm on the f22b1, no point in going up to 6250."

There is a point to revving up that high, to stay in peak power range....if you shift at max power then you have to build back up to it in the next gear, whereas if you continue in the gear, yea you lose some power but you are closer to the peak power once you shift. It's all about staying in the sweet spot, not peaking then shifting and building back up again.

 

yeah i know what you mean, but for people who think that only by reving to redline will yield more hp...they're wrong.