Petscar

Bought an 05 with 26k miles. Seemed a little slower than others i drove. Did a compression test with questionable results showing rotor 2 with both marginal results and failing results. The failed results on rotor 2 came in at 290 rpms on the original starter while rotor 1 tests were showing 190 rpms. This was why the test seem questionable. Since then i replaced the starter with a new S2 starter. The original starter was running at 190 rpms before being replaced. How it showed 290 rpms in the original compression test is where the test became questionable. Will be doing another compression test shortly after continuing to run it hard.

It had 2 previous owners. I tracked down the first owner. He did not know about redlining or premixing. The 2nd owner only started premixing the last year of ownership and occaisionally redlined.

I have been driving the car very hard. Redlining a few times each trip and taking it up to high speeds (115 mph). It seems after multiple runs, it has a little more power. Also i could never feel an increase in power beyond 5k rpms which many on the forum claim to experience. Usually it just seemed steady up to 9k rpms. However yesterday i started to feel a distinct power surge beyond 5k rpms. Is it possible to reverse to some degree low compression by blowing out carbon? I am not referring to worn seals here. As the car was well maintained as far as oil levels all its life, im thinking the seals maybe ok.

Loki

iTrader: (1)

Yes, self-cleaning the carbon can help liberate the seals and springs. Running the car hard puts it more into self-cleaning temperature and pressure. Engineering Explained on YouTube has a good video about this (for piston engines).

(but the net effect may not be noticeable in the face of actual compression loss due to seal wear)

sonicsdaman

iTrader: (3)

If you have bad compression you have bad compression, no amount of snake oil or bandaids will change that.

However track days/spirited driving are notorious for making your car feel better at idle and the whole rev range.

The 290rpm could have been a typo for 190, you didn't post all the test numbers but if you're numberss are 7 or less you fail nuff said. Side note rotor 2 normally fails first due to its location in the engine bay.




The power "bump" above 5k is due to the complex intake and all of the valves opening/closing at set rpms/loads. check the ssc, vdi, etc. they could be gunked up from oil at the neglect of previous owners.
Also I don't think I need to mention it but if you have not done so read the new owners thread this one

UnknownJinX

You can't really just go by the feels, though. Placebo is a hell of an effect.

Also, you shouldn't really feel a power bump. If you have driven any Honda with VTEC, it shouldn't feel anything like that. It should just rev smoothly to the redline with a fairly constant torque.