NEW dyno results... not good... need help.

[striktlyaccord]

So fellas, I went back to the dyno today to see how the car was doing, and I wasn't pleased at all.  Here's the scoop: I had my car dyno'd about 2 1/2 years ago under roughly the same temperature conditions (about 60 degrees) using a Mustang Dynamometer, and my results yielded roughly in the low 140s for both HP and torque, which disappointed me.  So today, I went to a different place that used a Dynojet because the previous place closed, and also because many people claimed that a Dynojet is more “Honda-friendly” and that Mustang Dynos tend to be "too conservative".  I currently have these engine specs (a full mods list can be found in sig.):

Engine:
K24A4 5-speed automatic, stock ECU
Mods:
K&N cold air intake
DC Sports 4-2-1 2-piece ceramic header
Custom 2.25” cat-back exhaust system with 2 resonators & A’pexi WS II muffler
2004 Acura TSX intake manifold
Power Rev Racing K24 thermal intake manifold gasket
Optima RedTop 75/35-925 high performance battery
A’pexi super ground stabilizer
Unorthodox Racing ultra ss underdrive pulley kit with Gates 70” belt
NGK premium laser iridium spark plugs
Mobil 1 5W-20 synthetic motor oil
93 octane gas (recommended 87)
Chevron Techron Concentrate Plus fuel system treatment every 5,000 miles

Please note, the biggest differences between the dyno runs from 2 ½ years ago and those done today are that today, I had on my lighter (I think) 15” steel wheels as opposed to my 18” summer wheels, I’m running 93 octane fuel as opposed to 87 octane, and my spark plugs are brand new Iridium NGKs.  If I remember correctly, when I dyno’d years ago, the tech told me that in the higher rpm range, things started to get shaky and fell off a bit, and this was possibly a result of a spark issue or maybe a coil issue.  In taking this into consideration, I did the most recent dyno feeling confident because I have new spark plugs.  (*Now, let’s put all flaming aside because of the fact that the dyno I used today is a different machine than the one I used before, but this was out of my control.*)

However, after 3 runs today, not only did I have some pretty bad shakiness in the higher rpms, but my average readings were 132HP & 134 torque… a roughly 10 HP & torque loss!!  I’m baffled!  The tech was pretty helpful (even though they only work strictly on Fords, and he debated my “Mustang Dynos are too conservative” theory because he felt that my previous readings could have actually been inflated because Mustang Dynos can be flubbed big-time, so I don’t know who/what to believe anymore).  He told me that my air/fuel ratio is fine, but I’m running rich at the top-end, maybe due to the fact that I’m running a stock ecu?  He also suggested that the rough reading in the higher rpms could be due to either (again) a spark plug issue or a coil issue, or maybe the fact that I have an automatic??  Now, for those of you who remember my “spark plug issue” post from a month or two ago (see here: http://elitecm.net/forums/index.php?topic=3488.0), you’ll remember that I had an odd pre-gapping issue, but upon contacting NGK, they said to leave them as-is, and the car seems to be running fine.  So, I’m just confused as to why the reading looks so bad at higher rpms, and why I lost power with what should have been more power-friendly mods.  I’ve attached a .jpeg of my dyno readings from 2 ½ years ago (sorry that it’s blurry), as well as of my best run from today for reference.  So, knowledge gurus, what the hell is going wrong??

OLD:


NEW:

[Mike]

There are a lot of variables to take into account here. The increased weight, and size of your wheels shouldn't have a large affect on HP and TQ numbers but, would hurt you in acceleration which may have caused the numbers to skew. Other common issues are the car not being strapped down tight enough. Auto transmissions are tough to dyno also was it in the same gear when the reading was taken. I would think that something was different that caused the numbers to be lower not something wrong with the car. I would look into the plugs again,  as a first step.

[Icebox]

the gas is something to consider as well since the stock ecu is tuned for 87 and not 93.

[Mike]

Do you always run 93?

[Icebox]

i do, but im runin a k242 w/ kpro, so my ecu is tuned to run 93

[accordguy04]

would it make a difference to the bad if it doesnt require 93 and you use it?  Like my 6-6 doesnt need 93 but I run it, does it not make a diff?  Would it put down the same dyno numbers on 87?

[Icebox]

 some point in time i read a thread where there had been dyno test done showing that the accord would run better on 87 than on 93 with a stock tune.  plus your just wasting money at the pump since the car isnt tuned for it.

[timot_one]

David is correct.  There's really no point in using premium with a K24 with bolt ons and the stock ECU.  Mike also brings up a good point.  There are too many variables that come into play.  The difference in wheels, the different dyno's, air temperature, etc... 

If you're really worried about the plugs, then pull them and make sure they're gapped properly.  It's not hard to do.

[accordguy04]

Guess Ill have to try just 87 next time I hit the dyno

[timot_one]

J30's are different.  They proved that there are small gains with premium.

[accordguy04]

Ahh

[NVA-AV6]

This is why I dont like dynos, many shops do not get thiers calibrated regularly and there is no standard of mesurement that all manufacturers follow. I have seen J36 builds read 320WHP on one dyno then a week latter go to a diffecent dyno and only read at 290WHP. The best use of a dyno is when you are actually doing mods, get a baseline just before the mod and then go back after the mod to see what the specific change was for the mods to the car.

[striktlyaccord]

Mike - When the car was dyno'd, we left it in D3 since I have an automatic, which makes sense.  I've been using 93 octane for about a year and a half.  I thought it might do a little bit for power, but I guess not.  I always thought it burned cleaner than 87 though... and I'm environmentally conscious.  Is this incorrect?  Now I wonder if the choppy readings after 5,250rpms are a result of the fuel not igniting properly because it's not 87, and the ecu is like "wtf"... 

Here is what a local Honda/Acura guy told me via e-mail.  The dyno shop owner recommended that I contact him regarding my dyno results since he's a knowledgable tech:

"Hi there Dave . Well looking at youre dyno curve I see that things get choppy at around 5200 rpm . To me that looks like the engine is looking for a timing change more than likely some advance . With all the mods you have done to the engine one would expect a power increase over stock . However without any way to fine tune things youre not going to see much of an increase at all . Something along the lines of a Hondata Kpro  or  Flashpro  would fit the bill here . I don’t even know if you can in fact get one of the mentioned management systems for that car as it is an automatic . As far as dyno readings go just ignore that as they are only a tuning tool and should be used when changes are being made to the tune or setups changed . I have tuned several Hondas over at Mikes and his dyno always seems to read a little lower than other dynos in the area but his dyno is very consistant and that is the most important aspect of tuning . 132 whp is pretty darn good for an automatic 4 banger Accord though ! So to sum things up an aftermarket engine management system with a proper tune will give you more power and utilize the mods you have done . Feel free to ask me more info if needed!"

I know that bolt-ons don't add a ton of power, and I know a proper tune would be best, but damn, I thought that maybe the stock ecu would acknowledge them a little bit and offer some gains.  Now, I just think that it gets used to them over time and just kills the gains.  Plus, does an auto tranny really eat up 30-40 HP from crank to wheels, because if that's the case, than my bolt-ons haven't restored any power at all, and that makes no sense to me!  And I agree with Paul... dyno's are useless unless you keep going to the same one after a new mod or tune is done to document the gains (if any).

[CrackerTeg]

An auto tranny does kill a considerable amount of power as compared to a manual. As for an actual number, I really couldn;t tell you. I beleieve the average percantage for that power loss is in the 20% range. Our engines don't respond as well to bolt ons like some other engines (ej25 and 4b11 for example) because of the way Honda builds these things. Anyway, I don't like to look at peak power rather the overall response of an engine. If the response as well as the efficiency has improved, its a win in my book.

[timot_one]

You can run kpro with your AT with the K-Tuned harness.  For what you have and what you're planning, I would stick with the stock ECU and leave things alone.