Hi-res, cap mod, table scaling and more
 

My setup:
1990 Mx5 1.6 with M45 supercharger, 550cc injectors (Denso case but modified to 550cc), MSPNP9093, IAT.
I've been running Megasquirt for two years. I added the IAT, the injectors and supercharger one by one.

The last couple of days I've been reading a lot of posts on this forum and the Megasquirt forum. And boy have I learned..
First of all, I didn't think the hi-res code would work on my ms1. But from what I've read, it will, no problem.
Second, the hi-res code gives me bigger tables. from 8x8 to 12x12. Sweet! And even better, it's able to be much more precise with the injectors!

So.. Correct me if I'm wrong here.
I can download and install the hr_10g or the hr_11d firmware on my mspnp9093. Both work, but the hr_11d has some changes that won't affect my car anyway from what I understand. But I guess newer is "better" ?
I should install a 100nF (0.1µF) ceramic capacitor on it. Described in the manual and in threads here on the forum (https://www.miataturbo.net/useful-sa...asquirt-13676/).
I'm guessing a max 100V ceramic capacitor will the trick? I'll add heat-shrink to it so that it can't short out on anything.
https://www.miataturbo.net/attachmen...ine=1461183266



The only "negative" thing I can find about hi-res firmware is that it doesn't support low ohm / impedance injectors. Since I installed mine without having to add any resistors, I'm pretty sure they're high impedance.

Since I'm running a puny supercharger, I'll see max 8 psi of pressure. That means max 156 ish kpa.
I'll need to re-scale my tables for max 160 kpa and for 12x12. What kind of increments should I use for kpa and RPM?

Any other mods or upgrades I should do with the ms while I'm at it? I've read about " A better Spark Out circuit ". I did have problem with it popping, but it seems to have disappeared after a little tuning.
A variable TPS, not just on / off as it is now ?

If your MSPNP is a 1.3 revision C, it already has that capacitor installed.

Thanks Matt. I'll check that out. Is it written on the case? I've got the good old white and red case.

Any input? Am I wrong?

it should be written on the label on the bottom.

Yes.
But am I correct about the other things? Like injectors impedance ?
And how should I scale my fuel / spark table? What increments? Let's say 170 kpa max (I installed a smaller pulley this weekend and I'm seeing 8.5psi +).

Check your injectors with a multimeter to determine their resistance.

I would use 8 rows for 100 kPa and below and 4 rows for boost.

Thank you Matt. When I'm buying another megasquirt. I know where I will buy it from.

Checked the sticker on the mspnp. Version 1.3 rev c

Yes, that's already got the cap mod present. While the issue stood out with high res code, it turns out the problem was also present, just not quite so blatant, on regular MS1/Extra code. So when we figured out the issue, we made the fix standard across the board.

I'm going to do the update this weekend.
Download firmware.
Connect computer to MS.
Disconnect Ignitors.
Run upgrade.
Load MSQ and check values.
Plug in Ignitors.

What about the sensors?
From the manual at megasquirtpnp.com
"note that the firmware on your MSPNP unit has been custom calibrated for your car’s sensors and using firmware directly downloaded from the MS-Extra site would also need to be calibrated. "

How do I calibrate the sensors? Are we just talking about the IAT-Sensor?


Edit: Do I need to read up on easytherm? I see it mentioned in a lost of posts. Looks like my megasquirt should have been upgraed back in 08.

Edit2: Old but gold? http://ozmx5.com/viewtopic.php?f=4&t=19

The firmware included with the MSPNP is calibrated for both the coolant and IAT sensor.

Yes. But I want to upgrade to hi-res and the firmware would then be downloaded from the msextra website.

you have to find the post, i think on miata.net, where someone posted a version of the firmware loader that can open in 64bit if youre in a modern OS.

I can provide the .s19 file if you need. It used to be on my server online; youll have to remind me over the weekend when im home.

I have and old laptop with Windows XP I can use.

What is the difference in your .s19 file and the one here ozmx5.com ? View topic - HighRes firmware images for MSPNP ?

So I just downlaod the hi-res firmware, replace the .s19 files with your .s19 file and run download-firmware.bat?

Thanks for helping. Seems like I'm way too late to the party! :p

Nothing. MS1 firmware files must be created with the AIT and CLT scales built in, didnt know there were any floating around online still like that.

Ok. I'll just try the one I linked to then.
Do my instructions sound correct?

yes.

Thank you very much.
I'll do the upgrade, re-scale the tables and start tuning again.

I never got around to upgrading (the Windows XP computer was missing).
I've got the hr10g package from ms extra but I think I still need to replace it with a different .s19 file. The forum I linked to in earlier posts is down / gone..

Braineack, do you still have the file?