Eric,...
The folks in this thread trying to help you need complete information on your specific setup. Turbo/injectors/intercooling, etc..

I would like to know where did you source the MAP signal for the FIC and how you are handling the O2 map. AEMLOG should give you all the parameters for your log. It would be useful to see load, injector duty cycle and the rest of the values the FIC maps.

Maybe you should verify it. Mine was 15 degrees when factory was supposed to be 10. *Disclaimer* Five degrees too much timing may cause detonation. Your mileage may vary.

Or maybe you should just drive the shit out of it.


Do you know what an O2 clamp is, or why you might need one?

He has a 2000, so the timing isn't adjustable. Doesn't mean he shouldn't verify it, though.

OP, fill out your signature with your setup so we can help you.

Possibly light rod bearing knock being under-described.

Setup is as follows
Sr20 turbo (garrett 2554) (6psi wastegate)
Begi log manifold
Begi Separated Gas downpipe
Non intercooled
AEM FIC
AEM Boost guage
AEM Wideband kit
Stock injectors

Sourcing both the boost gauge and FIC manifold pressure signals from the back of the manifold where the brake booster hooks up to. I don't really know what i'm doing with the O2 map. I don't quite understand what I need to be doing there. I'm trying to do some more research on that front.

Eric, I am not an expert, but here are my thoughts. I do have some experience with the FIC and low boost non-intercooled FIC setups. Since you are not intercooled, your intake charge is going to be hotter so you probably need to have your fueling a little richer than most setups with an intercooler. On my previous non-intercooled M45 setup that proved to be true.

The big picture is that you should be using your O2 map to hide the extra fuel you are sending the engine while you are in closed loop operation. This is most pesky around the transition period moving into boost. If you do not do this, the factory computer will see your extra fuel via the unmolested O2 signal and pull your fuel via short term fuel trims and you'll eventually be back stoich in the transition part of the map (too lean for boost). Once the car goes into open loop operation, it ignores the signal from the factory O2 sensor. I do not know of anyone who has been able to adjust an FIC/6 in the factory offset manner to manipulate the O2 in concert with the 99-00 factory computer. My maps start at a zero row, 4.2 row, 8.5 row, then 12.7 row all the way up to 25.7 row incremented by one psi each row. I use this to make tuning easier. Generally you'd like to get the best resolution possible and still have headroom on the top rows of your map just in case. Personally, I use voltage mode on the O2 map and load a -.19 value in all cells starting at 13.7 psi up through the map. This means that when the car is in closed loop and moving towards boost, the computer thinks the car is lean and will expect to see/add more fuel. I have corresponding edits in my O2 maps for these rows. I've had my FIC running boosted for about a year now, and this works for me. YMMV! Some folks do it differently, using a neutral value in this transitition area (the O2 clamp method). Usually you are heading towards open loop in these parts of the map and once it goes open loop, only the fuel you are adding has to correspond with the extra air your turbo puts in to arrive at the desired mixture for a particular level of boost.

Hope this helps. I'm sure other more experienced members may have comments/corrections, but this is what has worked for me.

Just curious where you are picking up your wastegate signal pressure?

Outlet of the compressor.

Without an intercooler i had to run 16-17 degrees of timing, anything over that would ping (6psi)

Whats the stock timing at that load? 25? 28?

I was going to check my base timing, but i forgot that I removed the cover behind the crank pulley. ::face palm:: I think what i'll do is little by little retard the timing 1* at a time.

Here is a link to a youtube video of what the ticking sounds like.

IMG 0646 - YouTube

Your AFR gauge is jumping around a lot, but the fact that 14-15 shows up quite a lot under load is a pretty good clue as to what's going on. I wonder how bad your pistons are by now.

What should it be under light load?

You should be somewhere between 12:1 to 12.5:1 under load.

So you are 14.x AFR under load? That's lean as hell for acceleration even without positive manifold pressure.

Stock timing under high load is very dangerous.


Your children may already be dead.

AFR during load bouncing between 14 and 16...

In for the melted pistons pics.
https://www.miataturbo.net/attachmen...ine=1359663440

Just so ya'll know, I'm only pushing on the throttle about 10% more to get the sound come up. And the afr definitely become richer with more throttle.

What is richer? with 10% more throttle you should be at about atmo or even boost at above 3k rpm... in other words less than 13 afr quickly going to 12afr as you push boost.

15afr will burn up your motor. To make things worse the stock ecu pushes tons of transition timing at 10% throttle since originally that would be 40-50kpa.

The only way to safely operate your car at it's current tune is @ idle in your driveway. Enjoy!

Turn the boost up to 25psi, the ticking goes away.

What should my next step be if making the afr super rich doesn't fix the issue?