This is my first post in this forum but I have been gathering information from it for about a year or so. First let me introduce my car and basic engine mods:
* 1996 (1.8L) with 70K miles
* Toyota COPS using iridium plugs gapped at 0.035"
* 50/50 water methanol Injection Injection starts at 120kPa
* 550cc injectors
* FM turbo kit with GT2560R
* FM standard intercooler
* Max MAP 190kPa
* Coolant reroute
* FM crossflow radiator with the stock fans (will replace those fans soon)
* MSPNP2 engine management.
* 91 octane Texan gas
This is what my AFR table looks like:
And I have verified my VE table tune to be good with a wideband and megasquirt log files.
Because I had no decent turbo spark table after installing my megasquirt I came to the forum looking for something to base mine off of. I came accross Brain's replies to the following post:
Flyin Miata Spark and Fuel Tables
Reply #12 shows two base tables made by FM. In my first attempt at a timing table I used the '01 table version for some reason. I heavily modified it and ended up with a crazy table that I assume was giving me knock. I honestly try to pay attention to my engine noises and I cant discern knocking, or "marbles rattling in a can" kind of noises. With the crazy table I came up with I must have had the noises. Anyways this is what I came up with:
I used this table and the car MOVES.... and fast I must say.... Since I am a total tunning noob I continued to read posts because I was super insecure about the safety of this table. Well long story short I was not able to find anyone running the timing numbers I was.
Then, I came across another post by Brain in miata.net. For reference the link follows: Any one want to share their ignition map ? - MX-5 Miata Forum
I noticed he was running 93 and using a table with much lower numbers than me so I based my second attempt at a timing table on Brain's table 3 on reply #3 of that post. Because that table is a 16x16 and MS2 only has a 12x12 spark table I wrote a program to translate the larger table to a 12x12 format. This is what my program came up with:
Notice the MAP column is a little different because I am not boosting as much as him. I must say that the software I wrote is in a very preliminary state and it might have bugs. The tables look almost identical (I am open to arguments).
The problem is that once I burned this table into my controller it made me really flaccid. It felt like a great deal of power was gone. I am not saying that Brain's table was bad or anything but this happening raised some questions. One was: is it possible to get more power if you went beyond MBT?
If not then that means that I am not reaching MBT with Brain's table. Sure, I understand every engine is different but I should have been relatively near.
So to gain some of my lost power at WOT I increased the timing by 5 degrees in the region of boost where I start injecting methanol (120kPa+). The resulting table is this:
Power came back, not sure if it came back entirely but it felt pretty good. I would need a dyno to know for sure. Even though I added +5 timing throughout the boost range the numbers are nowhere near of what I had in my first attempt (about 7 degrees less actually
). I have an electronic detcan and no knock is detected. I guess I must have a wax filter in my ears or something. Is know something that I should be able to hear loud and clear when it happens? Hell, if I run my engine at 7kRPM and rattle a can with 10 marbels inside I would be able to hear the can over the engine noise any time. So loud.