Hey Guys, I just had the AA SC installed about a week ago on my 98 M3. I also had the Gen 3 and TP installed. My question is how long does it take or what kind of break in period is there before I would expect to get the max rwhp? Reason being, the car got dyno'd at AA with 280.8 rwhp. I was told I would be close to 300rwhp and that after a couple of weeks I should re-dyno and expect the car to be there. Is this true? Being the car is OBD II, does the ecu need time to adjust?

NEiL

They have a 98 M3 s/c dyno on their site that shows 275 hp. You're doing better than that. Are you unhappy? Does the car not feel fast?

The car does feel a lot faster then it was, but I am just a bit concerned that with the combination of TP and Gen 3 that I am not considerably higher then their prototype car that has 285rwhp. That is what I believe they claim on there website? However, I was told that in a week or so the car will be quicker and to re-dyno to get the proven results.

I don't know... Every car is different and you can't really hold your numbers up vs another car and expect more...

Picking up an additional 15whp is alot, esp from just ecu adaptation...

does your car feel faster than my bros car? He is supposed to be around 315 rwhp but like he told you he is having some software issues so we don't know how much he is at. Although we are sure he has some power.

Amir's car felt strong even though he said he was losing power. I'm not sure my car is up to par with his, however I am still running on stock clutch/flywheel. I guess the real test will come in a week or so when I dyno.

NeilM3,

There have been some reports that people are losing horsepower on a slipping clutch. This happened to RyanC.

JC - supporting vendor now? Nice!

Good luck with your endeavor!

ESS also claims that the car will become faster as the ecu adapts to it's new environment.
Also, I know that different weather affects an engines performance. It's not paranoid to expect that AA would post dyno's from cooler, dryer days if they pulled better numbers.

...except for the fact that the dyno software corrects the numbers to an SAE standard, so temp really isn't a big factor in the reported numbers.

Hmmm. Learn sumthin' new ever day.

Ryan,

>>...except for the fact that the dyno software corrects the numbers to an SAE standard, so temp really isn't a big factor in the reported numbers.<<

Perhaps to a degree. But, Im not too sure about this. Think for a minute. A NA car will perform a little differently on a 40 degree day than an 80 degree day. But, do you think it will perform as differently as a FI car operating in those two conditions? Then, how would the dyno know how much to adjust for? A FI car after running several back to back pulls on a hot day, particularly if its an SC application sans intercooler, will suffer a great deal more than will a NA application. I think the temp adjustment will adjust the dyno's behavior in the different temperatures. But I dont know how it would account for the greater amount of degradation the SC car is going to suffer over an NA application.

Paul, the dyno makes corrections based on humidity, altitude and temp, which should factor out most of the power differences due to climate differences. I do agree that it won't capture everything, as relative temps can have an effect not only on air density, but for instance how warm the engine compartment may be, which can have an effect on intake manifold temp (as an example). As you have stated on your own dyno runs, applying different correction factors compared to none at all show a significant difference, but I don't think that power changes as a result of non-corrected temp/humidity/altitude data will be significant. Using the same dyno, which applies a standard correction factor, should net comparable data IMO. I've dynoed past cars in a variety of temps (sub freezing to 80 degrees), and results haven't been noticably different between the two. Certainly not anything more than what runs on the same day will vary. Of course, I've also ran 3rd versus 4th gear and not noticed a difference either, so maybe it's just my cars? ;)

Right.. The dyno software will make corrections based on temp and humidity. What it wont do is make corrections due to any heat soak conditions the engine is in due to multiple runs on a hot day. And clealry, the non intercooled or water injected FI car will suffer much more from this than the cooled ones, and the dyno sw wont do a thing to even that out.

Even if multiple runs arent involved, the dyno sw still wont do a thing to correct the fact that some FI cars DO have intercooling or winjection, and some dont, and on hot days, the latter will produce much worse results than on cold days. All cars will produce worse results on hot days than on cold days. The dyno sw will correct some of this. But it cant possibly correct the fact that the intercooled/water injected FI cars will produce better results than will the non intercooled/water injected FI cars. Given the same correction factor, the non cooled FI cars will do worse.

So, the concerns that Alex expressed, when applied to fi cars without cooling still apply. Better results at the dyno will be had on colder days on non intercooled/winjected FI cars than on hot days, despite the dyno correction sw.

...like a White Knight, riding across the desert on a fine Arab charger...to my emotional, forced induction, rescue...

:drink1:

I still think any variance due to climate, not accounted for by the correction factor, is minimal. If a car can't make reasonably consistent power, then whatever the dyno reports is probably pretty accurate as an average of what that car can be expected to make.

Look at it this way; the numbers on the screen are the equivalent hp and lb-ft numbers you are making. If your first run is 320hp, and your last is 300hp, you still made only 300hp on the last run. If I understand your point correctly, Paul, you're saying the dyno can't be counted on all that much because if doesn't make up for the missing 20hp from my example, but I contend that there is no missing 20hp. The fact is, you are making only 300hp on the last run. That is not the same as taking the measured hp amount, and correcting it to a standard based on simple math (air has a density of a at n temp, and a density of b at 2n temp, so hp changes from y to z). Those corrections are just modifiers to a formula, but they can't correct for unknown changes to the underlying data being passed in to that formula.

The point is valid though, that if a car can't or doesn't make consistent power across several dyno runs, you probably should compare similar runs only then (first versus first, last versus last). But if a car can't make pretty consistent power for 3 or 4 back to back dyno pulls, it probably needs some attention to why this is.

>>If I understand your point correctly, Paul, you're saying the dyno can't be counted on all that much because if doesn't make up for the missing 20hp from my example<<

No...All Im saying is that if you have a SC car with no cooler or winjection, and youve driven the car say 50 miles to get to the dyno in 100 degree weather, you will get a very different result on the dyno then if you were to test the same car, driving 10 miles to the Dyno in 30 degree weather. And Im saying the difference between the two results will be greater for this car than for an intercooled or water injected car. And the reason is that while the dyno software will correct for temp and humidity, it wont correct for the added effect of heatsoak on the non cooled engine.

>> but I contend that there is no missing 20hp. The fact is, you are making only 300hp on the last run. <<

Of course. IM not saying the dyno results are in any way not accurate. I think you are misunderstanding what I saying. My remarks are relevant for the guy who wants to show the Max amount of HP his car can make. If he wants a plot of the max hp is setup can make, and if hes not intercooled or water injected, then the dyno correction factor alone wont zero out the deleterious effect of the heat soak he'll encounter in the above example.