Learning to write maps

[mcleansc]

I'd really like to learn how to write my own maps. I've done a smattering of research on here and did a basic tuning course through HP Academy. From my minimal research on this forum I've read the guys who do it have done it for a long long time, on multiple engines and platforms.

Realistically, as a layman, is it worth my time even trying to learn? I know that little I don't even know how little I know if anyone who has taught themselves has any resources worth reading and wouldn't mind sharing thatd be great.

 

[GreyNBlueE92]

Just jump in, read V8Baits guide and start with a stock map from mhd. It's a lot of fun but you can also blow your car up so be careful lol

 

[shushikiary]

You'll find many people won't post for fear of creating another "tuna" on the market. They also love to keep things close to their chest as a marketing tool.

Reality is what you learned from HP academy is a good set of basics, and then every car is different. You can easily take tuner pro and the proper xdf with a bin file and start tuning, just have to make sure you know what you're doing not to blow things up.

For the N54 you'll want to understand what the key tables are and how they work. For boost control WGDC base is important as well as the PID tables and the tables that control max DC, etc. You'll want to know the fuel scalar tables and target AFR tables. The timing tables are obviously important too. The vanos tables are interesting and there is documentation out there from BMW on how the angle is measured, duration of the valves, etc. Knowing when to overlap and when to not, etc can really help turbo spool on some setups, but you have to know the setup and understand the dynamics.

I learned most of what I know from knowing how cars work in general, reading about valve timing, finding posts on the forums, etc.

 

[BEAT_ITN54]

It's all relatively easy. All you really need is mhd and tuner pro. As suggested the v8bait guide is useful basic rundown.
Check out the link and it should be somewhere aswell as many xdfs and free bins to experiment with. Like anything new start with small changes until you have a better grasp of the system. I'd personally opt to use mhd new pre made bins for there 3.0 update and use the custum boost control feature. Oem code has several tables that effect boost target and can take awhile to get the hang of it. If you you have understanding of fueling and igntion aswell as diagnoseing hardware issues then just experiment with little adjustments, log, repeat. These motors do run leaner than what hp might of suggested being direct Injection especially on ethanol.

File Finder · dmacpro91/BMW-XDFs

Contribute to dmacpro91/BMW-XDFs development by creating an account on GitHub.

github.com

 

[Raptor001]

Where can I download the v8bait tuning guide? Thanks.

 

[BEAT_ITN54]

Where can I download the v8bait tuning guide? Thanks.

Gtihub

 

[mcleansc]

Thanks for all the replies, I've decided to at the very least learn the terminology and wha the values are and how they effect the car.

I've already bought a book V8Bait recommends in another thread and considering the full blown tuning course with HP Academy.

BMW-N54-Tuning-Resources/Documentation/N5X Tuning Spreadsheet.xlsx at main · Corbanistan/BMW-N54-Tuning-Resources

Work-in-progress XDF definitions files for the N54 platform, and possibly more resources for backyard tuners in the future. - Corbanistan/BMW-N54-Tuning-Resources

github.com

That's the V8Bait spreadsheet for anyone who, like me, was struggling to find it.

 

[wheela]

Thanks for all the replies, I've decided to at the very least learn the terminology and wha the values are and how they effect the car.

I've already bought a book V8Bait recommends in another thread and considering the full blown tuning course with HP Academy.

BMW-N54-Tuning-Resources/Documentation/N5X Tuning Spreadsheet.xlsx at main · Corbanistan/BMW-N54-Tuning-Resources

Work-in-progress XDF definitions files for the N54 platform, and possibly more resources for backyard tuners in the future. - Corbanistan/BMW-N54-Tuning-Resources

github.com

That's the V8Bait spreadsheet for anyone who, like me, was struggling to find it.

What was the name of the book v8 bait recommends?

 

[mcleansc]

What was the name of the book v8 bait recommends?

'Maximum Boost: Designing, Testing and Installing Turbocharger Systems (Engineering and Performance)'. I understand loosely how turbos work but this book seems excellent. Knowing fully how turbos work will help me better understand what I'm doing when playing with boost. It was on an older post I found while trying to locate his spreadsheet.

 

[wheela]

Thanks for sharing, i'll have to pick this one up

 

[mcleansc]

I've still been plodding away with this and have found another book worth a mention:

•‌Engine Management Advanced Tuning by Greg Banish

Really enjoyable read and useful for referencing when tuning as well (well, when I start tuning ha). Below are also a number of YouTube videos I found helpful. Be warned, the info could be wildly wrong and I wouldn't have a clue, but they helped me understand a bit more about the tuning:

•

- This guy is RFP Tuning and from googling I can see some controversy surrounds his tunes etc. I'm not getting involved in that, just giving a source of info.

•

- I found this useful for adjusting the fuel scalar and the logging process. I've watched a buttload of HP Academy and they use a dyno in order to adjust load and RPM cells there and then, watching this showed me the manner in which we do something similar on the road.

•

- 2nd video from the same guy, this time adjusting boost. I was initially confused as to how we target boost, this taught me it's done by load (through a comment in the comments section) I wrongly assumed there'd be a 'Boost Target' table, and was confused when I couldn't find one on TunerPro.

HP Academy also have free videos, I won't post them all but here's a link to their page: https://youtube.com/@hpa101 - You can also get access to free webinars on their site, I've actually taken part in a few and Andre is really friendly and helpful. I'm still tempted to splurge and buy the course. They also do a Podcast, I've been listening to that while working on my side business, and although its not explicitly for teaching, you still learn a good deal from listening to them (and it's very informed guys talking about cars, what more do you want ha).

Once my car is road legal again I'm going to attempt my first map

 

[mcleansc]

Got another fantastic book worth a read:

How to tune and modify automotive engine management systems - Jeff Hartman

Just finished it today and coupled with a lot of YouTube videos im getting a much firmer grasp on tuning.

One question that hopefully someone can answer though. Ive been going over logs from my custom tune many moons ago and noticed some pretty conservative timing. It was done by Ken so I don't doubt for a minute it's correct, but the maximum timing is only 8⁰ (99RON). Is it recommended we stick with relatively stock timing as without a Dyno we dont really know if our changes are increasing power or just increasing wear? As a reference it made 430whp and 717nm to the wheels on stock turbos @21psi. So not exactly slow. But just wondering.

 

[wheela]

Thanks for the additional reference! I'm going to have to read through all these when I get a chance

I can't answer definitively, but I noticed when I came to the n55 platform, timing values are much lower than my last platform (Mitsubishi 4g64/4g63). Apparently it's due to direct injection vs. port injection and good turbulence in the airflow into the cylinder. Someone please correct me if I'm wrong, but my understanding is the fuel atomizes to much smaller droplets which burn faster, so you need less spark advance to hit peak cylinder pressure at the right time during the power stroke.

How much load & rpm are you at with 8 degrees and 99 ron fuel?

 

[mcleansc]

Thanks for the additional reference! I'm going to have to read through all these when I get a chance

I can't answer definitively, but I noticed when I came to the n55 platform, timing values are much lower than my last platform (Mitsubishi 4g64/4g63). Apparently it's due to direct injection vs. port injection and good turbulence in the airflow into the cylinder. Someone please correct me if I'm wrong, but my understanding is the fuel atomizes to much smaller droplets which burn faster, so you need less spark advance to hit peak cylinder pressure at the right time during the power stroke.

How much load & rpm are you at with 8 degrees and 99 ron fuel?

Yeah I think you're right on the direct injection requiring less timing mate (at least as far as my knowledge goes), but after Googling it I got results of guys running 13, 15 and even someone who accidentally ran 18 degrees timing advance.

Personally I think Ken is right not to mess about with timing without the use of a Dyno. Although, I was wondering if we could incrementally increase timing after each pull until the knock detection starts pulling timing, then dial it back a bit to maybe get MBT. But without a Dyno it's just guesswork. I've been comparing the stock bin to the V6 MHD stage 2+ OTS bin and again theres minimal changes to timing.

I got 7.9⁰ @ 6393rpm, actual load 175.1 and req load 195.1.

 

[wheela]

Yeah I think you're right on the direct injection requiring less timing mate (at least as far as my knowledge goes), but after Googling it I got results of guys running 13, 15 and even someone who accidentally ran 18 degrees timing advance.

Personally I think Ken is right not to mess about with timing without the use of a Dyno. Although, I was wondering if we could incrementally increase timing after each pull until the knock detection starts pulling timing, then dial it back a bit to maybe get MBT. But without a Dyno it's just guesswork. I've been comparing the stock bin to the V6 MHD stage 2+ OTS bin and again theres minimal changes to timing.

I got 7.9⁰ @ 6393rpm, actual load 175.1 and req load 195.1.

Slowly incrementing timing, until onset of knock (without a dyno) is what they'd do back in my Mitsubishi days. The caution there was if you're running e85 on those lower compression 4g63 engines, the octane on e85 was great enough that you could get beyond MTBT before running into knock with this strategy. So like you said, a dyno is a really useful tool for making sure you don't advance too far (assuming you've got the octane).

On n54/n55, I suspect if you're running 93, you're probably always going to hit an octane limit before MTBT when turning things up. So I'd think advancing timing until onset of knock and then backing off a bit should be a good strategy

You could probay use draggy times to gauge power instead of a dyno, but I'm sure that will have less resolution than a dyno.

If you're on a custom tune from wedge, I'd assume he's either balanced out timing vs. corrections for your octane and engine as part of the tune iterations, or is at least using timing values that he's already verified through tuning others before you.

Thanks for sharing your timing/rpm/load values! I hope to start self-tuning this spring in prep for throwing my big turbo on, so I appreciate all data points

 

[mcleansc]

Slowly incrementing timing, until onset of knock (without a dyno) is what they'd do back in my Mitsubishi days. The caution there was if you're running e85 on those lower compression 4g63 engines, the octane on e85 was great enough that you could get beyond MTBT before running into knock with this strategy. So like you said, a dyno is a really useful tool for making sure you don't advance too far (assuming you've got the octane).

On n54/n55, I suspect if you're running 93, you're probably always going to hit an octane limit before MTBT when turning things up. So I'd think advancing timing until onset of knock and then backing off a bit should be a good strategy

You could probay use draggy times to gauge power instead of a dyno, but I'm sure that will have less resolution than a dyno.

If you're on a custom tune from wedge, I'd assume he's either balanced out timing vs. corrections for your octane and engine as part of the tune iterations, or is at least using timing values that he's already verified through tuning others before you.

Thanks for sharing your timing/rpm/load values! I hope to start self-tuning this spring in prep for throwing my big turbo on, so I appreciate all data points

Ohh I didn't even think of going beyond MBT before being knock limited that's a good point thanks for that mate. Fortunately I'm running 99 RON so like you say I should hit the knock limit before MBT. I know a Dyno guy who doesn't charge much for power runs so I can always go in before farting around, then go back and see if im making more torque.

I did think of Dragy or an accelerometer but there's so many variables that can effect a pull I think Id struggle to pin down what was making me faster/slower.

100% with you as well on balancing the timing Vs corrections. The car is a dedicated race car now and with conditions constantly changing at the track I really want to be able to change things on the fly and eek out every bit of power I can.

I'd appreciate it if you keep me in the loop on your tuning experience, I'm really enjoying learning all this and any info would be awesome