New to versa - BNR S4 tuning

Discussion of tuning specific to MAZDASPEED6/MAZDASPEED Atenza/Mazda 6 MPS vehicles
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buttons252
Posts: 7
Joined: April 10th, 2020, 1:47 am

New to versa - BNR S4 tuning

Post by buttons252 »

Hello,

A few weeks ago i bought a mazdaspeed 6, then another two weeks later just for parts. One needs pistons, the other is currently my daily driver (stage 1)

Versatune pro
OBDlink SX
Cobb intake / SRI
Muffler delete
Billet wheel K04 (i suspect its a cheap china turbo)
-----
Parts not yet installed but on hand
BNR S4 v2
3" downpipe
new o2 sensor
Grimspeed EBCS
3" catback
HPFP
Forged manley pistons
Forged manley rods
clevite bearings

My daily driver had a nasty hesitation in the midrange. I cleaned the maf but still saw wild STFT of 25-30% swings. I ordered new O2 primary sensor. Before installing it, i loaded up versa base 93us v 2.04 map. Immediatly the problem was gone. After driving 50+ miles STFT stayed under 5%. I thought a maf cal might help ,but shocked this worked. Ive used Cobb ATR to tune 3 mazdaspeeds and my experience has always been boost based open loop. Generally i would do a maf cal, then data log 3rd / 4th gear. Target AFR 11.8 at WoT after 4000rpm. add some timing, add some boost.

With the versa, I increased the load by 10% at 4000-5500 rpm for 1.55 - 1.8 range. Increased wastegate duty cycle in the same area by 10% added 1 degree of timing. Car feels really good, logged 246g/s which i think is good as it gets for a stock ms6.

I am just starting a thread to introduce myself and get started because im sure ill need some help with my bigger turbo setup. I plan to use an E-tuner but i really enjoy the tuning and tweaking myself. I miss the huge treasure trove of missing threads on mazdaspeed forums. Ive been searing through these forums, but a lot of the threads are dated 2012.
Last edited by buttons252 on June 15th, 2020, 1:50 pm, edited 1 time in total.
buttons252
Posts: 7
Joined: April 10th, 2020, 1:47 am

Re: New to versa

Post by buttons252 »

Now that ive had more time to work on my map, i do have a question. I enabled megaspool yesterday and tested it (not actually launching) It was slow to build RPM, once it hit 4100rpm it was showing 6 degrees of knock. If knock normal during megaspool??
buttons252
Posts: 7
Joined: April 10th, 2020, 1:47 am

Re: New to versa

Post by buttons252 »

I have the BNR S4 installed with a 3" downpipe now and 3" JBR intake. I scaled the maf values up 20% then a crude maf calibration (not perfect yet) I am still dealing with the same problem I had with the K04. I cant hit load targets. I thought the stock exhaust was holding me up, but it must be something else.

Attached is a 3rd gear log and my tune. I am running E30 / 93 oct mix. Currently I hit 2.2 Load at 4000 rpm, then it tapers down to 1.8 at redline. Wastegate duty cycle was dropping to 0 at redline when i was targeting 2.1 load. I bumped it to 2.3 and now im getting 27% WGDC , but i dont like targeting 2.3 and hitting 1.8.

Power Mods:
BNR S4
3" downpipe
CPE TMIC
EBCS 3 port mode
JBR 3" intake
HPFP

My goal is to hold 20-21psi to redline and then start working on faster spool. My best g/s on the K04 with stock exhaust was 246. Now ive hit 305g/s but the car only feels faster after 5500rpm and its pretty marginal.
Attachments
VersaTuner Logs615.zip
(20.28 KiB) Downloaded 248 times
David E30 Octane - Grimmspeed Interrupt - BNR S4 v2.04.vtune
(106.13 KiB) Downloaded 218 times
buttons252
Posts: 7
Joined: April 10th, 2020, 1:47 am

Re: New to versa

Post by buttons252 »

I think I found my problem. I didnt update the absolute limit tables for overboost protection fuel / throttle cut. Now i am hitting 22psi at 4k and it tapers down to 19psi at redline. My goal is to hold 21-22 from 4000 to 6500. I am still targeting 2.1 Load but only getting 1.9. Normally we increase the boost, but i am still not hitting my boost targets either.

Anyway, excited that i am getting closer. I do really regret this CPE TMIC. My first log boost intake temps 104f. I pulled over, reviewed logs. flashed a new map. did another pull, 140F.
buttons252
Posts: 7
Joined: April 10th, 2020, 1:47 am

Re: New to versa - BNR S4 tuning

Post by buttons252 »

After more research, went out and logged Injector duty cycle. Much to my surprise i am hitting 95% at 5500rpm at only 20 psi. I suspect that is the last thing holding me back. I certainly dont feel comfortable increasing that value. I am going to dial in my maf calibration and maybe pick a slightly leaner AFR. Currently targeting 11.0 but was thinking 11.6
mituc
VersaTuner guru
Posts: 1324
Joined: December 17th, 2011, 2:47 pm
Location: Iasi/Romania

Re: New to versa - BNR S4 tuning

Post by mituc »

So a few things:
- if you are using a TMIC you need to be aware of the heat soaking when not moving and live with it. once the car is moving it's going to be fine. Get a WMI kit and this will fix the problem and also preserve the response of a TMIC over FMIC;
- ethanol mixes without auxiliary fueling will get you to the limit of the factory injectors quite quickly. Especially in your case when you target 10.4AFR (way too rich!). I'd up the injector duty cycle from 90 to 100%.
- The MAF cal at least has to be on-point, yours is off across the entire board by quite a lot. Besides the fuel specific gravity you need to account for the extra oxygen present in the fuel and tell the ECU to inject more. You do this by enriching your MAF calibration, meaning you up the values a bit. I'd start with 10% from the one in the last tune you posted.
- ethanol burns slower, and if you target very rich AFRs it will burn even slower if at all. Target at least 11.5 at WOT, eventually you may end up targeting 12 or so.
- in your tune the overboost protection tables are left to the ones from an OTS base tune. Set them to like 245-248kPa for throttle reduction and 4-6kPa more for the fuel cut.
- What boost controlled do you have? I assume it';s not the factory one, even though the load and boost compensation tables are left for the factory EBCS.

I strongly suggest to consider purchasing a custom e-tune from a reputable tuner. At this pace your tuning endeavor will not end very soon and it's a shame not to see all those nice parts you put on the car not work at their potential.
2008 Cosmic Blue Mazda 3MPS
Built engine + WMI + GTX3071 gen2, ~509BHP @34PSI
2008 Icy Blue Mazda CX7
Stock engine and exhaust (YES!!), JBR3" + GTX2867 gen2 + Autotech HPFP, self-tuned to 330-ish BHP
buttons252
Posts: 7
Joined: April 10th, 2020, 1:47 am

Re: New to versa - BNR S4 tuning

Post by buttons252 »

Last night i changed my open loop AFR target to .8 or 11.68. Updated the timing limit for the load values i am seeing with the bigger turbo and downpipe. Then went to my favorite back road to log a 3rd gear run. Virtual dyno has me at 359hp, 100% IDC still. Was grinning like an idiot for the first time in a long time. I am not comfortable going over 90% IDC so i am going to dial it back.

I have pistons, rods, bearings, exhaust manifold that need to go in then i am going to sell one of my speed 6s. decided not to have "winter" and "summer" cars. No room to park or store an extra car.
mituc
VersaTuner guru
Posts: 1324
Joined: December 17th, 2011, 2:47 pm
Location: Iasi/Romania

Re: New to versa - BNR S4 tuning

Post by mituc »

100% IDC is fine. above 105 is not fine any more because the spraying continues during the compression stroke.
You can set the IDC limit to 100% no problem. We are running that for years. This is different than port injected cars where IDC above like 80-85-90% (depending on design) means spraying against a closed valve. With Direct Injected engines 90% is not a hard limit any more.

Because you're running E30 once you are close to like 95-97% IDC you can stop targeting load (leave a room of a few perfect to still have some for those cases when the ECU wants more enrichment such as traction/stability control, knock mitigation, and so on) and you can increase timing. E30 can accept a lot of timing, at load 2 and 6000rpm 14-16 degrees of timing (depending of the octane of the actual gas mixed with ethanol) is quite common.
2008 Cosmic Blue Mazda 3MPS
Built engine + WMI + GTX3071 gen2, ~509BHP @34PSI
2008 Icy Blue Mazda CX7
Stock engine and exhaust (YES!!), JBR3" + GTX2867 gen2 + Autotech HPFP, self-tuned to 330-ish BHP
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