[rusEfi] Hunchback 1991 Miata NA/NB2 rusEfi official racecar #20

[AndreyB]

Great news: I was able to record the fuel miss. Now the easy part - finding the firmware bug.

https://sourceforge.net/p/rusefi/tickets/299/

[AndreyB]

I think I've fixed the misfire - https://svn.code.sf.net/p/rusefi/code/trunk/misc/logs/1991_miata_hunchback/20160626_misfire_fixed.7z

for 400 seconds RPM was in the 1044-1097 range

[Dial0]

Nice.

What was the issue / what change did you make?

[AndreyB]

I've changed one symbol - there are two buffers for fuel scheduling, one should be used to run the car while the other is used to prepare next fuel schedule. The bug was that the same one was used for both simultaniously.

[puff]

Was it specific for miata only?

[AndreyB]

Was it specific for miata only?

Not really. Maybe more probably with low-event-count triggers.

[tomiata]

I picked up the fix late last night, and it's a definite improvement. I tested briefly, idle is smooth.

[AndreyB]

Racing at http://www.thompsonspeedway.com/ this weekend

Between life and one of the team members quitting pretty much zero improvements were made to the car Still OEM ECU, still 1.6 engine.

Hopefully I would at least have log files with real timestamps this time, that's not much progress since May

[Thommm]

Nice, an endurance race? I've got stuff dialed in pretty well up to about 4000RPM (running out of injector room), if you want to switch to standalone I can send you the tune I use to daily my car, will be a good starting point for further tuning.

[AndreyB]

Nice, an endurance race?

Yep, http://www.24hoursoflemons.com/
This time we are trying 3 drivers instead of normal four to have more seat time. It's brutally hot here, we'll see how it goes...

[AndreyB]

Another Miata has just blown a Torsen diff during the test day. I love how their spares were packed, doing it like this next time!

[Thommm]

Nice, an endurance race?

Yep, http://www.24hoursoflemons.com/
This time we are trying 3 drivers instead of normal four to have more seat time. It's brutally hot here, we'll see how it goes...

I wish we had that in the Netherlands, it looks so epic for so little money. We do have trackdays, but not like lemans on a budget :p (or none that I know of at least). And that's one hell of an, uhm, efficient way of packaging, do you even swap the trans if it blows on the track?

[AndreyB]

do you even swap the trans if it blows on the track?

trans swap is what, 2-3 hours?

The race is 10 hours on Saturday and 5 hours on Sunday, if you get issues on Saturday you fix those before Sunday.

[Thommm]

Ah, didn't know it was split in two days, did know it wasn't really 24 hours because most cars probably wouldn't finish in that case xD

[AndreyB]

They usually have one true 24h race a year, I've driven http://rusefi.com/forum/viewtopic.php?f=3&t=822 in a true 24h in Texas. I've learned that I do not enjoy racing in the dark

[AndreyB]

Race weekend logs - stock ECU running the engine without O2 signal, rusefi recording. https://svn.code.sf.net/p/rusefi/code/trunk/misc/logs/1991_miata_hunchback/20160813_thompson.7z

Interesting fact: a lot of lean zones in the logs?!

Issue https://sourceforge.net/p/rusefi/tickets/307/ - two files are shorter than I expect them to be, wonder if the firmware has crashed during two stints.

[Thommm]

Haha, nice shot! The log (I picked rus0813_084545_andrey) looks, uhm, weird to say the least. If it was running at an AFR of more than 1:20 it probably not even run, let alone feel normal, I think there is something wrong with either the connection or your wideband. Although it weird that in the no throttle situations the AFR looks sane? Also, if you overlay "duty" and "afr" in megalog viewer, they follow each other almost to the pixel on my screen, isn't "duty" the injector dutycycle (or what it wants it to be since the stock is running the car)?

[AndreyB]

More about that race two weeks ago:

Thompson Speedway is a short track with plenty of turns, perfect for our stock 1.6 engine

The second race was even better than the first one, we got extremely lucky again! Zero mechanical issues - the only unplanned stop was to bump up the setting on the idiot light from 90C to 97C - it was REALLY hot that weekend. The hood was hot to touch with bare hands. One of the guys have rented a coolshirt system and this has totally saved his and my asses.

We also got lucky with a last minute substitute driver - his write-up of his first ever wheel to wheel event is at http://forums.24hoursoflemons.com/viewtopic.php?id=33556

So Alex turned to be the fastest driver between us noobs - https://www.youtube.com/watch?v=xXiw0epT1h0 - but he made a mistake not braking on time so his fast stint turned to be short.

My partner driving - https://www.youtube.com/watch?v=O4T0nL7iJfE

And that's me driving until I ran out of SD card. At some point I was gently pushed a bit off track but the guy has decided not to turn himself in so neither did I - https://www.youtube.com/watch?v=R9MELv4GqDw

[AndreyB]

http://www.murileemartin.com/UG/LNJ16/0113-DSCN1940.html
http://www.murileemartin.com/UG/LNJ16/0114-DSCN1942.html
http://www.murileemartin.com/UG/LNJ16/0115-DSCN1943.html
http://www.murileemartin.com/UG/LNJ16/0497-DSC_7323.html
http://www.murileemartin.com/UG/LNJ16/1114-DSC_8177.html

[stefanst]

How is progress coming along, prepping for Halloween Hoopties at the end of the month?

[AndreyB]

Car is pretty much ready, we will swap the driveshaft tomorrow as a preventative care and we should be good to go. The only thing is that new parts are sometimes failing in the most adorable fashion

MAP sensor finally works, I have doubts regarding location but if things go really good maybe I will second racing day under rusEfi control. We'll see

[AndreyB]

Some fresh duct tape and this car seems ready for http://www.24hoursoflemons.com/events-results/article/196-halloween-hooptiefest

[AndreyB]

Looking at the weather forecast I will spend this weekend in a similar way

[video][/video]

[AndreyB]

It's important to tighten wheel nuts. If you choose not to tighten wheel nuts, be sure you have both space spindles, not just one. If only take one spare spindle to the track and not tighten wheel nuts on the other side, well... you miss the Saturday party at the racetrack.

[stefanst]

So tightened nuts are not a guarantee of a successful race, but loose nuts are a guarantee of lack of success?

Sorry man. I wish I had a spare spindle. Will you be OK for Sunday?

[AndreyB]

all good to go

[stefanst]

Any videos and data logs from the weekend?

[AndreyB]

Here's the fastest driver in the wet, end of Saturday

[video][/video]

[AndreyB]

Half compulsive miata buying disorder, half we do need a gearbox and a rear spindle.

$250 no diff no panels but 99 with the BP-4W head on it which would probably go for sale once we have a VVT engine running.

[stefanst]

You're crazy. But the good kind of crazy