Turbo6TA

I can tell you something else that can skew the dyno numbers a little, thus making them not completely accurate ...

The dyno pull needs to be done in a gear that is most closely to a 1:1 ratio.

For both the M6 and A6 cars, that would be in 4th gear.

For the M6 cars ... easy, just leave it in 4th.

For the A6 cars ... You need to be using the paddles and select 4th gear in order for it to stay in 4th gear during the complete pull ... If you don't use the paddles it's just going to downshift into something else besides 4th gear when you go full throttle.

make sense ?

myredhead1

So basically, by using the paddle shifters to keep the car in 4th, you are essentially locking the converter to get a 1:1 ratio?

Turbo6TA

No, your not locking the torque converter. All you are doing is keeping the automatic tranny in 4th gear during the entire pull from start to finish.

Locking the converter in 4th would be ideal for the pull, but we don't have a way to do it at full throttle.

Husker C6

My tuner always uses 4th gear in my car. He will use whatever gear to get the 1:1 ratio in other cars.

Glad you are happy with your car NSF. Dynos are great for tuning and gauging increase from a baseline. Some people get way to caught up in the numbers only. The sound alone is enough to put a smile on my face.

Turbo6TA

Here are the C6 transmission gear ratio's for the various gears in the various transmissions (the top chart):

myredhead1

Good stuff.

Not So Fast

Exactly
This is what I was trying to impart, that different dynos show different numbers although the test car may very well be making the same HP.
Your experience is the perfect example. So many variables.
Thanks for the honesty and posting your results, much appreciated Turbo
Bobby
PS just read about being in 4th gear, that's what he ran it in and standing behind it while taking the video almost deafened me

BlindSpot

Hi Bobby:

I've PMed you as well, so if you just want to answer offline.

Can you describe the process the tuner went through (you attended the whole tune session, correct)?

I know you went in with CELs, so I assume the tuner started by accessing your tune, assume he made some adjustments, to extinguish the sensor CELs? He could have also made some standard changes to torque mgmt and trans at this time too.

Then he put the car on the dyno and did a pull? This would have established a baseline.

Important Question - How many pulls did the tuner do in total?

I know you don't have a wideband. Without an AFR, tuners will usually first get FTs corrected, if needed, then PE correct, then maximize timing in the PE range, all using HP/TQ. Even if they shorten this process and skip FTs, assuming the FTs are good, PE is where the performance is, and timing to complement that.

On dynos w/o a wideband, they look to maximize HP/Torque so they usually show a baseline HP/Torque, then make the adjustments as above, with a pull in between each event to ensure that specific change took hold in the right direction. Is that what your tuner did?

With the HP (363) that you published, what was the initial baseline HP? Should have been something lower than 363 if the tuner did a tune to maximize performance.

This is rough/crude. There is actually more to it than this, but these are the most important steps.

Thanks,

jaybee924

Waking up this thread. Thanks a lot because I just got done with my install and I was like what on the heart breaker dyno (Mustang Dyno). I don't have my sheet right now but my tuner is going to e-mail it to me. He said my 2011 GS LS3 M6 Baseline was 337rwhp with a AFE Power Dry filter, intake Shroud and V-Max Ported Throttle body. I went in with a CEL on I'm assuming due to the running lean the last thing I installed was the Ported TB.


My new mods: ARH 1 7/8" with Catted X-pipe, Hooker Blackheart NPP (Sounds very good and very loud), 160 stat and a cam close to Spin's specs Grind from Texas Speed (230/234 .615/.600 114+2) He has it idling at 600 to 700 rpm and oh you can hear it. I'm sure he left some of not a lot on the table and gave me perfect driveability to where I haven't had to change my driving style at all. He said my ending number was 407rwhp. When I get the sheet I will post it. I know it's not all about the numbers and the car is running very strong but I'm going to have it pulled on a dynocom or dynojet just to see where it somewhat lines up with others numbers. I don't track the car.

449er

There is no way that a 2011 GS dynoed 337 rwhp. A completely stock car would have in the 370-380 range

jaybee924

Mustang Dyno

Not So Fast

When I had mine dynoed after headers, new plugs, MSD wires, intake shroud I was disappointed in the numbers, since then I have done enough research on different makes of dynos giving very different numbers. I wont get into an argument on what a C-6 LS 3 should lay down because its a never ending battle of opinion's.
The following post is from a BMW forum and it shows what the difference was on the same day, same car on a DynoDynamics VS a DynoJet.
Take it for what its worth
NSF
http://www.e90post.com/forums/showthread.php?t=891691

98Pace

It's more telling that you picked up 70 hp with the mods. Nice gains!

Bruze

Yes.

As I'm sure has been stated ad nauseam, numbers are pointless unless you know the number you started with, the number you end up with, all being tested on the same machine.

Why such a big swing from make to make of dynos? Aren't they calibrated?

Not So Fast

Well that depends on the dyno and the guy running it now doesn't it
My guy said that a stock LS3 A-6 does exactly what was quoted on his dyno. So if you take the results from the thread I posted on the BMW forum test then mine would have come out from 363.5RWHP to 415.5 RWHP if it had been tested on a DynoJet instead of a DynoDynamics, and that's what I had hoped for
In the end it is all just numbers isn't it, the BS stops when the flag drops, don't matter what each dyno said.
NSF

jaybee924

NSF you might have the quote of the year: The BS stops when the flag drops.

When I get time I will take it to a Dynocom Dyno just for sh*t and giggles. Of yeah you remember that PM I sent you a while back X-pipe has yet to come. It's past the 6 month mark. So I took another route. SMH

HOXXOH

My first dyno pull with stock tune and a CAI was 306rwhp on a Mustangdyne. After the tune it was 320. So the tune itself added 14hp and the car went from 12.40's to 12.20's. A year later I added Z06 exhaust manifolds etc and a retune on a Dynojet with 382rwhp and went 12.00's. Several years and tunes (tune tweaks) and a few mods later, including twice swapping TC to a 3600 and trapping 125+ with 10.8's to 11.0's, I got on a portable Personal Touch Dyno in a Pep Boys parking lot and hit 411 rwhp. In late 2014 at a local group dyno day on a different Dynojet and with a 4000 TC, it maxed at 394 rwhp and the next track day went 10.80 @ 126+ with several bad plugs.

What that tells you is pretty much nothing, since no two dynos nor mods, nor track conditions were the same. Does it mean that all those guys who seem to have numbers in the 430-450 range will have better ET's or trap speeds than others whose numbers are 380-400? No again.

The bottom line is that dyno numbers don't have a direct relationship to performance with the exception of the 1st pull vs the best pull on the same dyno on the same session.

Turbo6TA

In a perfect world with a bone stock 436 HP LS3 on a dyno that has been properly calbrated to a SAE standard-day condition:

M6 trans .... 13% HP loss through drivetrain .... 379 RWHP

A6 trans .... 15% HP loss through drivetrain .... 371 RWHP

Not So Fast

A little more info for us to digest, fresh build stock LS 3 on an engine dyno FYI
NSF

HOXXOH

With headers that generally account for ~15 HP with a stock tune.