asmasm

iTrader: (1)

Is there anyone here with a really well tuned (street manors, starts up in all weather, accel enrichment...) naturally aspirated car who could post their project files? It would be great to have as a reference to check out when I have questions and can't find info on MT.

SchmoozerJoe

iTrader: (2)

Hey there Alec,

Here's the latest work in progress on my NA8 car.

The car last put down 135/109 on a dyno jet here in northern California.


(That tune is also included below.)

It's nice and very well behaved now on the street thanks to Twibs415's input on smoothing cells out and keeping the steps between cells at a minimum.
It'll be hitting the dyno again soon... hoping to break 140 on the NA8 long block. Just waiting for the latest 3d intake to be printed out.

Twib's modified NA8 manifold and NB injectors were just installed. Those three things will hopefully get me to break 140 next time out.



PS. "Starts in all weather" is relative for this northern California guy. Pretty sure the lowest temps I've seen for cold startup are in the low 60s. It might not help much for you folks who see snow on a regular basis.

asmasm

iTrader: (1)

Thanks.
Our Priming PW settings look really different- I am guessing mine being off the chart isn't ideal:
https://i.imgur.com/LxLpP7a.png

Also, our AFR targets are really different + I need to rescale mine to not include boost pressures:
https://i.imgur.com/jAw6UUI.png

My tune is on the right.

18psi

iTrader: (76)

Just my opinion: most of the "drivability" stuff won't transfer from car to car. In most cases, it's useless. You actually have to figure it out, and tune it.

But plug other's stuff in and report back how it goes for you.

Personally, I've done that a million times, and by the time I've made other's stuff work on my car it's been tweaked to the point that it has literally nothing left from the original settings I've copied.

So I abandoned that approach years ago.
Understanding what the setting does is infinitely more important than just copying it over, because there's way more than one approach that will work, and many cars require different approaches. The thing that sucks is that MS documentation is getting progressively more terrible with each year, making it that much harder to actually understand the different menu's and settings.

I can post 2 maps from 2 different cars, both ran perfectly, and the settings are not even remotely the same. Plugging in one into the other car results in garbage.

asmasm

iTrader: (1)

I am not expecting to be able to copy anyone's settings over but it is nice to have a reference to look at for a rough idea of what I should be doing.

18psi

iTrader: (76)

No worries, I understand. But even then that usually doesn't carry over.

For example: priming pulse and cranking pulse will vary greatly depending on your altitude/temperature/humidity/etc. it will also change drastically between return and return-less, and with different injectors. Your idle cells will vary greatly between injectors. Your accel enrich will vary between injectors, and also be significantly impacted by your ve map, how it's scaled, and how you have it set up (low bottom row, high bottom row, etc). For example: Dnmakinson made a great EAE thread that is really helpful, and yet his SFW table is backwards of mine, and both of ours worked fine. They were not even close to the same in data, or even the curves.

Just giving you input, by all means not stopping you from doing this
I just think that ultimately it will waste a ton of your time, and you will still have a poorly running car until you actually understand what the settings do and tune each to your liking.

Stealth97

iTrader: (5)

What Vlad says is true. For example, my car with long duration cams idles at 67-68 kpa and requires 15-25 degrees advance to maintain stable idle. Load that map on your car and it would fall on its face.

Schuyler

iTrader: (1)

<p></p><p><img alt="Giggle" src="https://www.miataturbo.net/images/smilies/gay.gif" style="height:21px; width:15px" title="Giggle" /></p>

18psi

iTrader: (76)

asmasm

iTrader: (1)

Well, between copying Joe's AFR table, running veal, and retuning accel-pump (at threshold 6 right now) the car is running a lot better than this morning. I will be curious to see how it behaves when it is dead cold tomorrow morning.

SchmoozerJoe

iTrader: (2)

Sounds promising.
I'd say 98% of what mine developed into was based on all the great info here on mt.net

That, and giving up on my stubborn "but the base tune has" attitude that finally gave way to the light (and gentle floors) that Twibs had been suggesting since day three of my MS journey.

I still miss the immediate starting nature of batch injection... But what can I say. Investing in an MS3 just to combine batch fire for startup and sequential for everything is is too silly, even for me.

Sadly I'm pretty sure 18psi would haaaaate driving my car. Then again, it's not often I find someone even more ---- than I am!

asmasm

iTrader: (1)

Since I already have this thread open I thought I would ask here. Can someone provide me with some help dialing out this lean/dip when blipping the throttle off of idle? In order to narrow down the cause I have:

Turned off fuel over run cutoff
Set the decel half of the accel-pump curve to 0
Turned off idle control
Padded the fuel level in the bottom of my fuel map

Youtube video:

Matt Cramer

Better to post a data log and MSQ, unless you want me to ask you to pull the same numbers I'd need off the data log out of the video.

asmasm

iTrader: (1)

Log and MSQ file are attached. I just made big changes to the AFR targets and have only done one veal drive since- most of the fuel map isn't relevant here. Also, once it gets dark out I will verify timing with a light. I set timing last year when I installed the megasquirt but I will verify it again.

asmasm

iTrader: (1)

my base timing was off by 2 degrees, which it wasn't before so I am assuming the damper is failing. Will check agains't cyinder 1 TDC soon but changing base timing didn't fix my issue.

asmasm

iTrader: (1)

Checking against TDC showed the damper has slipped. I am installing a VVT engine soon so I am not about to swap dampers between now and then. I made new marks on the wheel, reset base timing, then replaced spark plugs, and did more veal driving. The car is still showing the same dip / lean off blipping from idle. Blipping off of idle is one of the least important things in the tune but it would be good to figure out the cause. I already went around the engine bay with a propane torch checking for vacuum leaks but I think I will do that again.

Twibs415

iTrader: (8)

time based accel enrichments. you probably could used a steeper slope in the box. try that and report back.

asmasm

iTrader: (1)

As a follow up, switching to time based AE didn't fix it. I don't think the issue is AE related as it happens after AE ends.

I did manage to tune most of this out (it still does it a little) by really carefully tweaking the fuel map. I got the best results by recording the screen with a dslr so I could scrub the video footage for exactly what cells are being used at what AFR. I know I could have pulled this from log files but seeing the dot trace around the map was a really easy visual indicator to work off of.

18psi

iTrader: (76)

if you megalogviewer it will do exactly that for you. You can open the tune and watch it in real time

patsmx5

iTrader: (16)

I tuned this and made this part of my map PERFECT. Absolutely perfect afr's right off idle. Here's how:

Get the car up to temp. Have your target AFR map setup correctly. Start logging. Drive around in 2nd gear, and ride the brakes while feeding it some throttle. Use the brakes to get the RPMs low, and use the gas to bring the MAP value to a given cell, and cruise at this cell in STEADY STATE for several seconds. Then go to the next cell up (lean on gas to raise map, lean on brake more to keep it from accelerating) and repeat. This took about 20 min and now the off-idle response is literally beyond fantastic. I tuned my fuel down to 350 RPMs doing this. (350, 700, 1200, 1500, all the way to 4,000 actuallY)

Hot starts, cold starts, idle, torque under low RPM take off are all vastly improved.