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      10-21-2018, 11:34 AM   #14

Drives: 2016 F80
Join Date: Aug 2012
Location: Cary, NC

iTrader: (7)

Given how everyone here clearly loves real data, I went out this morning and did a series of logs (12 to be exact) against the stock tune (i restored my backup I took before flashing), and the MHD stage 1 tune, then plugged the results into virtual dyno so I could do comparisons. I created a custom profile specifically for the F30 RWD 335i with 8HP, I used SAE smoothing 5 (same as the dyno results I posted yesterday), and I corrected for temps, barometric pressure (52* and 30.2), and passenger weight. All pulls were done in 4th, DSC fully off, in sport + mode.

My first 4 runs were before I reflashed back to stock, the middle 4 runs were stock, the last 4 runs, I again reflashed back to MHD stage 1. I used the same exact 4 stretches of road for each set of tests, conditions were pretty much identical throughout, results were pretty consistent.

Here are the results:

Stock 278whp/279whp average, 291/286 max, 270/274 min
MHD S1 313whp/319whp average 323/329 max, 300/310 min


1. Best numbers and worst numbers achieved with each tune were consistent with the stretch of road used for each pull.
2. Using averages, the net pick up was 35whp/40wtq.
3. HP numbers on VirtualDyno for the stage 1 tune were in line with my experience on the real dynojet yesterday. TQ was less, my guess is this is due to using 5th gear on the dynojet while using 4th for the VD pulls.
4. Before everyone jumps down my throat about the use of VD, I've found to be a very good tool for doing like comparisons. You just have to actually go through the trouble of setting it up properly. Obviously it's not a real dyno, but it's not like I have one of those in my garage. I will continue using this methodology as I work through the process of refining.
5. I went back and double-checked my n54 logs. Max boost was actually 17psi for the 1+ tune, not 18.5 as previously mentioned. I played around with stage 2 for a very brief period, that's where the 18.5 number came from. Just mentioning it to correct the record.
6. I was surprised to see that the stock tune tops out at 9.5psi, I thought it'd be more like 8. The MHD tune is 13.5 as previously mentioned.

Regarding the numbers, I went back and scoured through the MHD flash thread, and found this interesting tidbit posted from MHD themselves:

"We state number at the crank, but measured here in Germany. From experience if you want a WHP Dynojet reference, substract 5% for RWD, or 10% for XDrive."

If you go to MHD website, they state the expected output for an EWG is "up to 370hp/520nm". Using their own guidance, this should equate to 351whp/363wtq. So something clearly does not add up.

Flame away :-)
2016 F80 M3 (Mineral/Full SO)
2014 X5 M Sport (Mineral/Mocha)

Last edited by TheBreeze; 10-21-2018 at 12:18 PM..