Optimal Boost By Gear Settings By Mods

[MEXICO NEW YORK]

Originally Posted by Simmadown115

I agree with the following to help these cars as free driver mods:

-comfort mode
-lower RPMs on launch control if going from a dig
-40rolls slightly ease into throttle if you need to on hit

Trial and error can easily show new F8x owners why this makes a difference without getting technical.

I already saw the difference from them when I have tried on a stock car especially with the sport + pedal.

With DCT I feel that riding to redline is the easiest way to give up power. The roll off on stock turbos stop making more power at 6k. Short shifting gets the turbos back into their optimal RPMs and the DCT helps keep you in boost. You can feel the difference in doing so in DCTs because the punch to your face when the torque comes back in way more prominent.

Remember: Power = (TorquexRPM)/5250. The faster you are is based on the integral of how much power you can keep during the whole run. If you're power is rolling off at a point where your power can instead keep increasing, you are summing a negative factor to your overall race.

I disagree, it was no easy task to obtain a hp curve to disprove your theory on stock turbos, but with Cary's help i did, and I do well upshifting around 7200, and it's not a big deal if i go closer to redline or if i upshift early around 7000. You make no mention of the impact the lower gear has compared to it's power drop-off, and that's why i do well compared to the hypothetical "next guy" with a different tune that also makes 600whp, but his power nosedives after 6k rpm forcing him to upshift to stay "600whp" but im "575whp", still in 2nd the lower gear (pulling harder)

[Simmadown115]

Originally Posted by MEXICO NEW YORK

I disagree, it was no easy task to obtain a hp curve to disprove your theory on stock turbos, but with Cary's help i did, and I do well upshifting around 7200, and it's not a big deal if i go closer to redline or if i upshift early around 7000. You make no mention of the impact the lower gear has compared to it's power drop-off, and that's why i do well compared to the hypothetical "next guy" with a different tune that also makes 600whp, but his power nosedives after 6k rpm forcing him to upshift to stay "600whp" but im "575whp", still in 2nd the lower gear (pulling harder)

I am glad you have a custom tune for the flattened torque curve but this thread was to provide feedback for those using the OTS BM3 tunes on how to adjust their dial.

The stock turbos on the OTS tunes have a heavy roll off, short shifting puts you back into optimal power instead of the heavy roll off seen in the OTS maps. See attached dyno for BM3 OTS maps below for the drastic differences in what you are talking about. Your custom tune will perform better by minimizing the roll off hence why you can blow by people riding to redline. The OTS maps will not. By going to a custom tune your tuner will decide the boots by gear he recommends for optimal performance.

If you want to start a debate on custom vs OTS then open another thread, but don't

[overlook637]

Short shifting does put the engine back into peak HP dyno sheet. However the engine is now transmitting less power to the ground, even though the dyno chart says you should have peak power.

The transmission has gears that alter the power before its transmitted to the ground. There are online calculators that easily show the power to the wheels in each gear with the optimal shift point.

Short shifting is mostly for NA engines not turbo engines.

[Simmadown115]

I just wanted to clarify the recommendations made on this thread, I can repeat this for MT but I wanted to clarify that for DCT short shifting Stage 1 BM3 is optimal. See attachments comparing the flat torque to the BM3 stage 1.
Reference: http://glennmessersmith.com/shiftpt.html

I was only robbing myself of 500 rpms from experiences before, but the rest shows that short shifting before redline is optimal based on DCT gearing.

Walking a BM3 stage 1 is expected with a flat torque curve. Riding redline on the BM3 stage 1 will just make the gap even bigger.

[Ed_rx7]

anymore?

[Simmadown115]

Too cold to do any testing in new england and I haven't had any feedback from users yet. I expect to have some more tire results in the spring.

I also plan to having Vbox testing to go along with the numbers.

[Ed_rx7]

Cool... I’m surprised you haven’t had a better response tbh... it benefits all users

[Simmadown115]

For anyone looking for a flat torque map without having to pay for it on a custom tuner, checkout the new BM3 updates below and we'll be running more numbers in the thread soon!
https://f80.bimmerpost.com/forums/sh....php?t=1579736

[1000hp]

Any updates to this?

I'd like to know what more people are using for 1st and 2nd gear.

I have BM3 stage-1, and I would like to just plow all of the power in 1st and 2nd gear, and see how much traction I have.
I currently have no issues flooring it in either gear on Michelin PSS.

Better yet... can anyone tell me what the OTS percentages are?

[hellokitty]

Stage 2 ACN91

20% reduction in 1st
10% reduction in 2nd

Seems to work pretty well but I could probably go a little higher in reduction since I still spin slightly in 2nd when it is cooler outside.

[1000hp]

Originally Posted by hellokitty

Stage 2 ACN91

20% reduction in 1st
10% reduction in 2nd

Seems to work pretty well but I could probably go a little higher in reduction since I still spin slightly in 2nd when it is cooler outside.

What tires are you running?

[hellokitty]

Originally Posted by 1000hp

What tires are you running?

Cup 2 (240)

[1000hp]

Originally Posted by hellokitty

Cup 2 (240)

Wow. Is stage 2 that much stronger than stage 1? My car hooks almost all the time.

[hellokitty]

Originally Posted by 1000hp

Wow. Is stage 2 that much stronger than stage 1? My car hooks almost all the time.

I wouldn't say it's night and day form stage 1 to 2, especially on ACN91. The downpipes add probably 15 whp and the tune maybe another 10-15 whp since it's octane limited.

[1000hp]

Originally Posted by hellokitty

I wouldn't say it's night and day form stage 1 to 2, especially on ACN91. The downpipes add probably 15 whp and the tune maybe another 10-15 whp since it's octane limited.

Judging by the dyno graphs, it looks like the torque comes on earlier with stage-2, which I like.
I'm also on the East Coast and have real gas, which helps.