Merc63

I went and dyno'd my car. Its 09 26000km and has Renntech stage 2 tune.

Renntech rates the tune at 511hp.

Dyno used: Dynojet SAE 1.10 Smoothing 5 Humidity 11% Temp 76F, 26.98in-Hg

1st run 5th gear, 365.72HP, 347.48 Torque.

2nd run 4th gear, 375.84 HP, 337.22 Torque.

The only fan they used was a little tiny air circulating fan, that barely moved any air.

They pulled up some past dyno's. There was a SL63 there, it pulled 369HP and 342 Torque in very similar conditions.

I can't confirm it was an actual SL63 that did those number, but that is what the file was saved under and the guy said it was a SL63..

So is it safe to say I did a good run for the conditions if the SL is only 4HP higher then mine? Or should I call Renntech and *****...

gsrjc

EEEEEEK

BerBer63

Find a new DJ with a better fan.

Brian GT PRO

Fans are a very large portion of the accuracy of a dyno, you need proper airflow, as well as you need to keep the room from getting filled with exhaust gasses that get reconsumed in the engine.

Merc63

The exhaust was piped outside.

Side note, M5 used to walk all over me pre-tune. After tune, I walk all over M5.

I think im putting down correct power, just the dyno had ****ty conditions.

MBH motorsports

If you post the chart it should be easy to see if your car was pulling timing, with the lack of fans. You should be able to see that with the way the HP graph looks. You need to have some sort of fan on the, or pointed at the radiator. then.... at least something else.

C63newdude

Ouch.... that is a very low reading no matter what, specially on a dynojet.

qship5

That seems low...I have Renntech stage 2 tune and pulled just shy of 400 whp on a Dyno Dynamics (399 whp and 390 TQ)

C63newdude

If I were to see a before and after Renntech tune I would be very solid on my conclusions. We know the after the mods dyno numbers but what about before?

This just gives me chills to think that a tune can cost thousands of dollars and yield questionable results. A before and after dyno is always a must.

superlubricity

Merc63, please post the dyno graph.

C63 Guy

Or maybe you can post a chart with the AFRs... But I know some people have real trouble getting those numbers.

Josh

superlubricity

miami1lt

Those are stock numbers...have you had your 1 year "A" Service? $100 says the dealer reflashed to stock...365whp is what i had in 5th gear before getting ECU retuned...while air is an issue, it shouldn't cost you 40-50whp.

HIRO63

I dont know if its true or not but does it rate lower on dyno machine that take the wheel off not the roller one? Like Dynapack, etc? People say that if you compare to roller type dyno and the one you take your tire off could get like 100hp difference with same car. Could this be true?

bushburninc63

baaah, it's just dyno numbers, you walked all over the m5, that is all that matters.

avengerboater

Haha. Come on, guys...let's be nice.

But, yes, dyno charts would be helpful.

jrcart

First things first, the 511 hp that Renntech is quoting is at the crank not at the wheels so if you went into this thinking you were going to get anywhere close to 500rwhp on a dyno you went in to it with an unrealistic goal. That being said I would still be a little concerned with those dyno figures, if Renntech is claiming 511 at the crank and we subtract say 18% for driveline loss you should be in the ballpark of 410-420rwhp however it appears you are only at about 375rwhp. Another red flag should be the Dynojet dyno, they tend to read on the higher side when compared to Mustang and Dyno Dynamics. Did you do a baseline dyno pull before the Renntech tune? If so what was that number? I was under the understanding that bone stock C63's were making 370-375rwhp.

I guess if you claim your car is beating and hanging with cars it was unable to in the past it must be making more power, but those are some very low number coming off a Dynojet.

Merc63

Well obviously its rated 511HP to the crank. That's common sense.

I have the stock ECU I should have brought it with me and plugged it in. Im going back there with the stock ECU to see. I know the car is definitely faster as my quater mile times dropped and beating the M5.

The car was pretty heat soaked. I was driving it all day hard then went straight on the dyno pretty much without a cool down. The intake was hot to the touch.

Either way I'm going back with the stock ECU and that will show the problem.

superlubricity

Do you have graphs?

When you go back, bring a USB/Flash drive and get your dyno runfiles.

If you send them to me I can help review the data.

Merc63

I have them. Ill have to scan them tomorrow and throw them up.

Vegas_AMG_C63

Did you put the C63 into Dyno Mode? Otherwise, you may be seeing that the system is interfering with the results.

When we initially dyno'd the 09 C63 with performance mods and just ESP OFF. The results were dissappointingly low #'s. After putting it into Dyno Mode, there was no problems and the car pulled excellent #'s.

I've heard from others that it wasn't necessary to put he car in Dyno mode and that they'd just turned ESP OFF. However, in our case, it was obvious that when we entered the mode, power was increased and when we were out of the mode, the #'s weren't very good.

Here are the instructions to activate "Dyno Mode":

http://www.youtube.com/watch?v=3tLtaMPS46o . The only difference I had was that once you get into the menu it was called dynomometer test and not "roller test". Once there, I needed to choose "Enabled". The other position (factory default) is "Off when Ignition is Off" and it was a bit confusing. In any case once it's enabled, you will see a message that says something to the effect of "you're now in diagnostics / test mode, ESP, EPB, ABS are unavailable."

Perhaps this will help...

superlubricity

I have found there is no need for "dyno mode" in our cars. I've done 60+ pulls with ESP off in Manual mode without an issue. It usually takes a couple pulls to get to peak power, so don't stop making pulls until your numbers are consistent. The first two pulls are always lower than the following pulls.

Merc63

Yes I was in Dyno Mode.

Car was also running RICH after 4000RPM or so. Could have been from lack of fans??

superlubricity

Did you scan the graphs? If not, at least take a photo of one and post it.

avengerboater

How lean? Lack of fans would not cause it to run lean...less air = richer. If anything, it'll just cause heat soak and result in lower power numbers. We need the graphs.