Im getting my G on the Dyno but it has already been mapped, does anyone have any stock data they can share that can help me understand my gains?

Even better if you have:

1. Stock View
2. Stock with Akrapovic and link pipes view

I can then compare this to my output having had the vehicle tuned?

Thanks

 

Having numbers from a different dyno and a different car is not a good reference point. Your G on the same dyno before and after any mods would have been better. Your numbers now are only a baseline for future work. Extrapolating to crank hp based on drivetrain losses is also not a good way of measuring gains.

 

Thanks - not ideal I know but I don’t see what other option I have really. I’m learning as I go - I had the tune done where the fitting of the exhaust was done and they did not have a Dyno 🙈

 

I don't have that, but to help understand gains I wanted to mention a 2007 G55 video I watched had roughly a 25% hit in drive-train loss. Successive runs decreased in power from heat soak.

It seems like the loss is on the high side, but normally a 2WD vehicle with an automatic rear wheel drive would lose about ~15%. With a 730 HP remap expectation, I'm guessing it would put down near ~548 HP. When numbers are corrected for weather and elevation, I think it is still helpful to look at other dyno graphs. The gas octane rating is important to know about too. Normally gas in California and some other US states is only 91 octane (unless it is bought at the race track). So if you have higher octane in your area, the computer may be able to add more timing w/out getting knock and put more power down.

 

Thanks - I’m booked in for a Dyno this weekend.

 

I dynoed my previous GL 320 diesel before and after a piggyback tune. Initial pull had a similar drivetrain loss of 25% which is typical for 4-wheelers. The tune increased the numbers to MB’s original crank numbers. You might save a trip to the dyno if you ask your tuner for a G dyno chart. The numbers won’t exactly match yours but you will be able to see the gains on the RPM range.

 

Are you suggesting that the stock numbers will be less when you are on the Dyno than the actual reality??

I guess I’m wanting to know BHP gain but also torque (Where my power sits), sport plus is now much smoother through the gears since the tune - through the gears it’s less aggressive! Or have I lost some torque/power in the lower ranges!

I don’t know I’m way outside of my comfort zone here of knowledge! But hence I was leaning towards getting it on the Dyno to understand more!

 

Manufacturer’s HP and Torque numbers are based on “bench” dynos with the engine on a stand.

A “chassis” dyno is what you will doing and will have to deal with the friction losses of the entire drivetrain which measures the power to the wheels.

Two completely different sets of numbers.

 

Good to know... thank you.

Apparently the G should be pushing 740BHP. I still want to see is though and also understand where the power sits now verses before...

 

Here’s the renntech dyno showing a higher factory stock number as explained on their site. Yours will have similar curves.

 

Thank you for this, I missed it when on the RennTech website when I was considering what map brand to get.

So I understand: If the quoted number is 585BHP then the actual is 605BHP on the Dyno and the RennTech device delivers 85BHP how do the get to 730BHP? I’ve clearly got something wrong!

Im assuming as I’ve got the full Akrapovich and link pipe system (which adds BHP) plus the ECU upgrade I should be pushing more than 730BHP..... Thanks for answering if you get time. 😊👌🏻

 

The chart is for a 2018 G63 and only good to see the gains from a tune. Best to reach out to the company that did your tune.

 

Stock g63 + akrapovic (no linkpipes) - 512 whp and 775 nm

 

I don't know how anyone with a newer G wouldn't go with RennTechs Hand-Held-Tuner (HHT) - if your changing downpipe/exhaust - you tell RennTech to correspondingly modify the tune.

HHT will Dyno 700hp+ no exhaust change - no turbo change - you just need to put in Aviation fuel for the Dyno or Road Run..

For a faster SUV - 2021 GLE63's that arrive at dealer's in just a few days.... 0-60 3.4, now that burning up the asphalt...

 

I have the GLE’s on order, but nothing beats the G for nostalgia! I also hunt a lot and the G is far better equipped for off-roading.

DMS are the UK’s best tuners so I’m very happy to go with them. I wanted a place of business in the UK should anything go wrong and RennTech don’t have that in the UK. DMS spend most the time tuning supercars 250K cars and upwards - those two things are what gave me enough security... But each to their own choice.

So far I’ve had no issues which is great, I guess I’m keen on the bragging rights from the Dyno. A little self indulgent I know!

 

That is serious torque being put down. I'd love to hold that ***** wide open. Nice power band.

The older 5 speed auto (722.6) in the G500/G55 had an amazing torque rating of 738 ft-lbs/1000 nm. I wonder what the current transmission can withstand.