i'm getting more power? but i didn't do anything? Options

[azian_advanced]

need some clarification:

to start off, i bought my car with 97,000 kms on it, and the engine was pulling alright w/o problems what so ever.. but now, i notice the more i drive it the stronger it becomes... i got the car nov 2005 and last summer of 2006 i noticed that it felt a little stronger than when i first got it. and recently, last sunday, i was on the hwy going 160 kms/hr (a little over 100 miles/hr) and it was probably my 3rd time ever going over 3500 rpms but never passed 4k. and at that speed i was actually nearing redline, then i reduced speed again.. did that about 2 to 3 times (i was not racing btw! i don't race. just to get the point out. i'd say it was more like a 'spirited run').

later i stopped at a coffee stop for donuts for a little while. when i got back to drive the car again, it seemed like i was getting more power for some reason. it was like i was getting another 10HP or so i think. the car would pull stronger and the rpm would rise quicker. it's been like that since last sunday. i dunno, but did that 'spirited-run' have anything to do with my engine getting more power? my car is now at 109,000 kms on the odometer. since the time i bought the car, i think there has been an increase of about ~15-20HP.

btw, nothing was changed in the engine or drivetrain. and i have no engine or performance mods at all (just suspension), so everything else is still stock. i've only resetted the ECU and performed regular oil changes . can anybody explain what's going on?

[azian_advanced]

We can take each other's car for a spin and then you'll know if the 15-20 HP is all in your head or not.

When did you reset the ECU?

during the summer at the same time when i did an oil change and switched from premium 91 octane gas to regular 87 gas.. i wanted to reset the ecu so that it'll tune itself to efficiently run on 87 octane.
and i might have overexaggerated, i'd say it was probably like 8-14HP

Well there has been talks about an engine loosing its power if you run it in low rpms all of the time. Carbon builds up in your engine if you don't rev it high enough alot. So when you took it out on that "spirited run" you could have burned enough of that carbon off to gain some extra ponies... thats what a volkswagon owner told me once.

i figured the ecu would program itself according to the driver's driving habits.. and i agree that carbon build up will naturally occur when driving constantly on low rpms.. perhaps i should occasionally start giving my engine more excercise on the hwy.

I did feel a difference driving around during a very hot Autum (September/october) day and the same night when difference in temperatures was about 20 degrees.

This was with the 3S-GE.

@azian: You dont drive past 4k rpms??

I barely keep it under 4k rpm when driving only for the first 15minutes/15 kilometers to get the oil/water temperature at the right numbers.

i can also feel the difference in power depending on different temperatures.. being in the center of the continent, during the summer i was able to feel the difference between our cold nights and hot days. it was as if the car was lagging in the day and then suddenly become a bit stronger in the evening.
oh and in this city, there are very few freeways (most of which are not my common routes) and most of the roads are not as wide and long as in bigger cities. and there are traffic lights and stop signs on nearly every corner (well sort of), so i'm usually driving an average of 60 kms/hr (~37miles/hr) and sometimes on 5th gear during very slippery conditions.. man, it sucks cuz the winters here keep me from driving at high rpms.