My '06 TSX is the first Honda/Acura I've ever owned, so I don't know if this is normal or expected behavior.

Like most cars I've owned, my TSX seems to have performance "moods". Sometimes it feels very fast, other times it feels merely somewhat quick. I attribute this to subjectivity from my own mood/attitude as well as measurable factors like air temperature, fuel grade, and the amount of pinging my engine has done lately... However, no matter what, I've always felt a very sharp rise in power once I hit 6000 RPM.

Last night I was on my way home and decided to wind up the ol' K24 on a freeway entrance ramp. I started at around 2000 RPM in 2nd gear and took it up to an indicated 7499 RPM (more or less anyway--haha). It seems my limiter hits at precisely 7500 on the tach, so I've gotten proficient at bringing the engine just shy of that point to squeeze as much high-lift cam time as I can

The acceleration felt quite good, however at 6000 RPM I felt no discernable switch in power. I heard a very clear change in engine noise, but power just continued to build up in a smooth manner. This is the first time the VTEC shift has ever felt so smooth. Normally I feel a very noticeable bump in power.

Down the road and I had another opportunity to merge onto a much faster freeway, so I did the same thing but in 3rd gear. Again the transition was nearly seamless. The change in engine noise was the only indication that something was different.

Has anyone else with a 2006 noticed such a variance in "feel"? It makes me wonder if my engine was peforming especially good below 6000 RPM, or especially bad above 6000 RPM... I have not driven the car today, but I think I'll try it again just to see how it behaves.

Regardless of the reason, I'd like the car to continue behaving this way. My TSX made me smile--the very mechanical roar of the engine coupled with a pretty damn smooth powerband all the way to the limiter--no obnoxious bump in power... it was a great ride home!

 

I feel ya.

I can hear the cam change at 6k, and it sounds aggressive as heck, but I'm not so sure if it's pulling an harder at those RPM's.
I kinda feel like it is, but with the noise factored in, it could be purely psychologically.

Also, the pull feels noticeably stronger on the 6MT, throughout the entire rev band.
On a 5AT test drive, it was more meh....

 

Did the 06 change the rev limit? It is 7300 on the 04/05.

 

Very interesting... Perhaps it was changed... or maybe the tachometer accuracy at high RPM isn't that great from car to car (+/- a few hundred RPM). This is what I've observed with my car:

During full throttle acceleration runs, my rev limiter engages consistently at an indicated 7500.
Rev limiter in neutral/stationary is exactly 4500 RPM.
The VTEC high lift switch occurs at an indicated 6000 RPM or just a tiny bit past.
Warm idle looks to be 750-775 RPM.
Cold idle seems to peak at 1500 RPM.

I'd be curious to hear what other 2006 TSX owners have noticed.

 

i have a 2006 6sp and it only revs to 7300....at quick glances it might seem like it goes to 7500 but it dosnt.

 

Rev limiter hits at 7300(and change), but the inertia on the tac makes it go past the rev-limiter which is just a false indication not a real RPM.

I have an 06 6MT and the amount of pull you feel in high-cam is very much dependent on the weather temperature. You will notice a bigger change during summer. If you ask people who have cold-air-intakes they'll tell you that after installing the CAI the power-delivery became smoother and the only thing they really notice in VTEC range is the engine's loud growl.

Another thing to note is that the VTEC range does not give you the peak torque this engine has to offer(that happens between 3000-4500rpm). It only makes up for the silly drop in torque between 5000-6000rpm. That's why the power delivery feels so smooth, because the VTEC makes the average torque curve a very smooth one. Without VTEC this engine would've been useless past 5000rpm.

 

fyi, for auto owners rev limit is 7000 rpm in full auto mode and 7300 rpm in sport shift

 

I think there was a thread before that talked about the vtec crossover point. The concensus was that it was designed to be a smooth transition, whereas the vtec in other cars will give you a sudden jump in power

Personally, my 06 has always had a smooth vtec transition. Yes, I can hear the cam change. Yes, it pulls slightly harder. However, it's still not so noticeable...someone could probably drink hot coffee and not get burned...

 

man, i thought i was crazy when i was wondering the same thing. sometimes the car feels fast and sometimes it doesn't feel as fast. this is under normal driving not revving it way up there.

 

Unlike some of you, my TSX typically has a very noticeable change in thrust once the high lift cam lobes come online--the smooth (and rather pleasant) switch I noticed the other night was the exception to the rule.

I drove the car today and noticed that the engine was back to its usual behavior. I suppose the smoothness I experienced the other night must be attributable to a really lucky combination of fuel, air temperature, and runtime engine parameters. Oh well...


Regarding the rev limiter--the indication of 7500 RPM couldn't be due to needle inertia. For one thing, the needle doesn't climb fast enough through higher gears (like 3rd gear) for this to even be an issue. The tach needle moves in a linear and well-damped fashion with no visible overshoot or lag.

Based on what I'm hearing, I suspect my tach isn't the most accurate thing in the world--but car instrumentation is seldom perfect anyway. Has the rev limiter value and hysteresis been confirmed, or is "7300 RPM" based on hearsay or in-car observation?

 

I'll second the noticeable g-force change when the VTEC kicks in (4 year old 80K).
And I run only 95/96 RON (UK).

 

When I drove the '06 loaners, the high cam change was fairly noticeable right around 6k rpm, and I can actually feel a small bit of push back into the seat feeling, as if the car actually has torque.

However, when I drive my '04, I cannot feel any difference, and none of the push back into the seat feeling. It even feels much more sluggish than the '06 across the rpm range.

 

What grade of gas are you putting in your car to make it ping? You should probably run 91-93 grade gas.

As far as the V-Tec goes in my '05 TSX it is very smooth. There isn't a jerk or anything. However, in my '02 TL-S there is a very noticeable difference in noise/power when the V-Tec kicks in. When it shift from first to second under heavy acceleration I can actually feel the front wheels break loose (The car is stock and the break loose is only for a second.) That makes the car feel fast!

 

I always use the highest grade available of course, which is usually 93. I think the crap that passes for gasoline around here is the cause of the pinging. I intend to install some cooler plugs in the car at some point. We did this to my friend's '03 TL-S which also had a pinging problem and it seemed to help quite a bit.

I'm getting the impression that the 04-05 TSXs had an inherently smoother powerband at 6000 RPM than the 06. Most dyno charts I've seen for the 06 show a pretty sharp rise in power above 6000 RPM.

 

The other day, after not driving the car for over a week, I took her out to stretch her legs a bit. I wasn't paying attention at the time, but I swear I felt kicks at about 5k, maybe even as low as 4500 rpm, a few times under moderately hard acceleration. And nope, I don't have Hondata. Anybody ever felt this?

 

Wow that is interesting. I've never heard of that. Is it consistent?