Hi everyone,

I am a new member on this forum. I joined up after I purchased my CPO 09' C63. It's black with black leather package. It does not have performance package, so no LSD. I really love the car and I'm enjoying reading many of the posts on here.

I apologize for not formally introducing myself before I started posting, but I just like to jump in. Already, I have learned a lot about these cars and the available aftermarket parts through reading this sub-forum. So, thank you to everyone that contributes.

The dyno was done on a Mustang dyno (I don't know which model -- I forget), but I have used this dyno on two prior occassions for the 5th Gen Camaro that I owned before I purchased this car.

The car put down 348.5 rwhp and 345.1 rwtq, corrected numbers. Without correction, the numbers were 316.3 rwhp and 313.4 rwtq. Below are the graphs. I have to say that with these rwhp and rwtq corrected numbers, when divided by the 451 and 443 respective flywheel hp and tq numbers, it shows that my car loses about 22.5% to 22.1%, respective to hp and tq, through the drivetrain. Personally, I think those are higher losses than normal. I believe normal drivetrain loss for these cars should be about 18-20%. So, it's possible that this dyno reads a little low.

Details about the run:

The temp outside of the dyno shop was mid 90 degrees F, humidity was low, around 12%, barometric pressure was around 29.9. in., elvation of Henderson is around 2000 ft. above sea level. I don't know what the DA was yesterday, as it can vary.

All pulls were made in 4th gear. We weren't sure about which gear to use, but we looked up some threads on this forum and decided that 4th gear made the most sense. I didn't want the car to go 155 mph without more air (I think the car reached 120 mph at the end of the runs or slightly less). Personally, I've seen stronger fans than the ones we used, but the dyno shop that I was at does have larger fans, but they weren't being used.

I normally use 91 octane because I live in CA. But the morning of the dyno (yesterday morning), I put in 100 octane. I still had about 1/4 tank of 91 octane left in the tank, which is a little over 4 gallons. I added 7 1/2 gallons of 100 octane.

I drove the car about 15-20 miles after I put in the 100 octane, making a couple of stops and a couple of restarts before I went to the dyno.

I'm not sure if I drove around long enough for my car to register the higher octane. But, I just wanted to disclose as much detail as possible.

We made 4 runs, with the last two being nearly identical. During the first run, the tuner that was operating my car on the dyno, had the car in manual and in 4th gear, but he said when he pressed the throttle all the way to the floor the throttle clicked an dropped the trans down into 3rd gear, so he aborted the run. I don't understand that, because the trans shouldn't drop down in gear on it's own when you're in manual.

He also said at one point the trans shifted up to 5 gear for a moment when the car was getting close to redline in 4th gear. We didn't record that run either.

The last two runs were in 4th gear. I wan't in the car when these automatic shifts were happening in manual mode, so I'm just relaying what the tuner said.

We had a data logger (not sure which one) plugged into the OBD-II port and the data showed that the throttle would open to 62% max during the runs.

I'm satisfied with the numbers because they seem pretty normal. The dyno operator said that the weather wasn't a great day, but it wasn't bad. He believes his dyno reads a little on the low side and he said he wouldn't be surprised if my car made another 15 rwhp on a better day.

 

Numbers are on par with what a mustang dyno should read for a stock C63 on 91 octane. These cars have 18% drivetrain loss, 20%+ is an old school number or is reserved for AWD.

 

That's what I thought. So, that's pretty cool.

What do you think about the details relating to the octane that my car was likely running during the test?

Thanks for the response.

 

I don't believe that's enough time for the ECU to recognize the higher octane and adjust accordingly. So I'd say it's a 91 octane dyno. Probably felt stronger on the drive home though

 

You would think!

But... This trip to Henderson/Las Vegas wasn't about fun and dynos. It was actually me chauffeuring my lovely fiancee around while she was taking school exams and running errands.

One of the errands that we ran was picking up what seemed like 150 lbs of her stuff (books, binders, coolers, etc) and loading my trunk and back seat until both spaces were full.

Bottom line, I think whatever power I gained with the higher octane was negated by a much heavier car. Call me crazy, but the exhaust sounded slightly throatier.

 

Haha! Yeah ok you got me there!!!

 

The problem with mustang dynos is that you can make 'em read just about whatever you want...experienced it myself. You can change the hp@50 and the weight values, and you'll get something different. Maybe what you had for those variables was accurate, so numbers look right. I would say that a c63 w/ driver and full tank of gas though weighs about 4200 lbs, 180 lb driver.

 

Yeah, it seems right, although I know what you're saying.

JFYI, I had 2/3 of a tank of gas, but that isn't that big of a deal.

Also, I dynoed my previous car (a Camaro) there, and the weight he used for that car was 3850 lbs and the results were right there within the normal range.

And again, here, it seems my car is within the normal range. So, perhaps entering the exact weight isn't so important. I admit that doesn't make too much sense. But, the results are what they are.

Anyway, for me it's a baseline.