poormxdad

Just throwing this out there for discussion. I looked through the tune. Is it possible that +/- 15% EGO allowed the car to run around town with that VE table?

jonnie5

No datalogs. AFRs seemed okay. I’ll be honest, I didn’t have my eyes glued to the gauge. I’ve trusted the owner of the shop for years; he sold me on his tuner. I thought I would be getting a high quality tune and I wouldn’t have to worry about a thing. Similar to the two previous tunes I had received from my previous tuner.

This has been a learning experience for me, to say the least. If I ever go down the built motor route with a custom tune, I’ll be doing my due diligence and looking @ the tune as soon as it’s done.

jonnie5

Question:
Are there any concerns with the fact that the AFR table only goes to 200kpa and 6000rpms?

The other tables go to 250kpa and 7500rpms.

Z_WAAAAAZ

If it were your VE or ignition table, then yes it’d be a problem. Your AFR table should go to 7000 and 250kpa at least for your setup, but won’t cause any issues as is because the table is so uniform. Once you’re past 6k rpm, the Megasquirt will just follow what’s in the 6k cells, same goes for your max load (200kpa) cells. Since they’re all the same horizontally and vertically, you’re still ending up with the intended AFR targets.

jonnie5

Thank you for clarifying.

One thing I forgot to mention. I was running Bosch EV640cc injectors but when tuning, they said that they adjusted injector settings and the injectors are actually 740cc. Does that make any sense? Could that cause issues if they adjusted the injector settings incorrectly?

poormxdad

Nothing changes the fact your VE Table is complete ****. Your AFR Table is incredibly non-standard--way too rich at the bottom, and your spark table is very aggressive. You should peruse the tunes at Trubokitty.com for what a good starting point would be.

However, your injector numbers (as well as a lot of the rest of your tune) are the same as mine. I'm running the original Flow Force 640cc injectors, which are Bosch, and are probably the same ones you're using. The actual injector flow depends on the fuel pressure. The NBs run at 60 psi, so Nigel at Flow Force had me use 788cc as the size of my injectors in Tuner Studio under the "Engine and Sequential Settings" tab. Yours is still set to 650, but that should present zero problems. The other injector numbers look fine.

SimBa

Jonnie, the AFR table you posted in the original post could be a single column and it wouldn't change a thing about the tune.
Because the targets never change on the horizontal axis, the target AFR will be the same at idle and redline. The table is setup to ONLY account for manifold pressure for target AFR, regardless of RPM.
It should account for RPM, especially for highway mileage.

I have parts of my AFR table that are the save value in a whole row, but that's mainly in boost. IMO resolution on your AFR table isn't the most critical, but you certainly want some, and if you have a table that large you might as well use it.

We have interpolate and smoothing buttons in tuner studio. I'd bet anyone on this thread could make a better AFR target table in a minute or two.

My 0.02, it sounds like you like the shop and have a good relationship with them. Make sure you understand what you're looking at and go talk to them. Don't run in screaming that they charged you for a garbage tune, especially if you don't have a good understanding of what you're looking at. Maybe you can sit down with the shop owner and see if he can explain why the tune is the way it is. I'd also double check and make sure the tune you shared with us is the tune that's supposed to be on the car. It almost seems like this was a rough draft/starting point and not a finished product.

Again, I'm no pro, so take it with a grain of salt.

oreo

I am also running 94 octane fuel and stock 9.0 pistons/compression ratio.
My 250kpa timing line looks very similar to yours. Your 225kpa and 200kpa lines have much more timing than me.
Of course that does not mean a lot, because I spend very little time at 200 or 225kpa so not much tuning of any sort was done at this boost level.

BTW, the MSQ file you attached, has the fuel injector set up as 650cc/min
When you data log a pull, are you maintaining a 11.5afr as shown in the AFR table?

Do you belong to any local Miata clubs?