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Discussion Starter · #1 ·
searched and couldnt fine this. Does anyone have a graph or table of what the stock ecu timing looks like under boost? im just trying to do some research and compare some other tuners standalone ignition tables with the stock ecu. hopefully with a enough research il be able go full standalone soon and start doing some self tuning.
 

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The graph is going to vary from type of gas used to what the other correction tables are trying to do to it. Might not be of any use. Rumor has it at max NA load the ECU runs roughly 20* of timing though.
 

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Discussion Starter · #3 ·
i plan on going with the AEM EMS sometime soon. im pretty confident i cant get the fuel alright but what would you suggest to be the best way to go and start tuning the ignition. i know i should set it up conservatively first and then add timing until it detects too much knock, but how do you know whats conservative to start off with.

ignition timing just scares the hell out of me but id rather try to take a stab at it and learn than take it to a tuner and not know anything.
 

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The stock timing curve can be datalogged if you have an OBD2 scanner and the ability to datalog it.
 

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This is a good starting point. MBT isn't found so you'll need to tune the upper loads on a dyno.



I went over quite a few threads on how to tune a timing map. But in a nutshell, strap the car to a dyno. Add timing till you're not picking up much power anymore. At that point back off timing and pull about 2 degrees out to add a safety buffer for bad gas. This is assuming the motor isn't knocking of course.
 

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This is a good starting point. MBT isn't found so you'll need to tune the upper loads on a dyno.



I went over quite a few threads on how to tune a timing map. But in a nutshell, strap the car to a dyno. Add timing till you're not picking up much power anymore. At that point back off timing and pull about 2 degrees out to add a safety buffer for bad gas. This is assuming the motor isn't knocking of course.
Those 12s and 13s are pretty conservative IMO. Must be some really crappy gas.
 

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Those 12s and 13s are pretty conservative IMO. Must be some really crappy gas.
Yes it's very conservative, you can get away with another 1 or 2* of timing but here's the catch. If you're on a thicker headgasket your motor is a lot more prone to knock with the extra degree. Is it worth it to add the extra timing?
 

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I would not consider the stock timing map conservative for boost, nor NA for that matter.

The stock knock sensors are very sensitive to knock however and will pull timing at the slightest hint of knock.
 

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Discussion Starter · #9 ·
This is a good starting point. MBT isn't found so you'll need to tune the upper loads on a dyno.



I went over quite a few threads on how to tune a timing map. But in a nutshell, strap the car to a dyno. Add timing till you're not picking up much power anymore. At that point back off timing and pull about 2 degrees out to add a safety buffer for bad gas. This is assuming the motor isn't knocking of course.
yea i saw a thread with the map you posted above. but how did you know what numbers to start with.
 

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I would not consider the stock timing map conservative for boost, nor NA for that matter.

The stock knock sensors are very sensitive to knock however and will pull timing at the slightest hint of knock.
We were refering to the area of the map where 12s and 13s were found. I would also not consider the NA map to be conservative for a boosted car. If the stock ECU doesn't pull timing quickly enough, you could be in trouble.
 

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yea i saw a thread with the map you posted above. but how did you know what numbers to start with.
Experimenting. I found 35'ish degrees during cruise with a 14.6 to 14.9 air/fuel ratio gave me around 20 MPG mix of city/highway all highway I'd be in the 23-24 MPG range. Under boost, I found I can run about 2* more timing at 10 lbs and up but the knock levels were too high, could have been a lot of engine noise but I'm not taking the chance. I was able to make a little over 380 rwhp at a peak of 11.8 lbs of boost with the higher timing but it wasn't worth the risk.

I'll tell you this, I'm well over the 100k mile mark on a stock long block minus the headgasket and injectors, 50k plus miles boosted, when you tune for reliability and longevity...you need to tune on the conservative side. Some people don't have access to a TIG welder or have lots of weekend time to pull a motor and rebuild it so it's better to be down about 10-20 rwhp while keeping everything as safe as possible.
 

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We were refering to the area of the map where 12s and 13s were found. I would also not consider the NA map to be conservative for a boosted car. If the stock ECU doesn't pull timing quickly enough, you could be in trouble.

Definitely.

BTW, does anyone know what units are on the y-axis of that table?
 

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Definitely.

BTW, does anyone know what units are on the y-axis of that table?
That table I made is X = engine speed (RPM) and Y = load (inches for vacuum and PSI for boost). This is not the stock timing map. It's a generic timing map I came up with that works for a boosted IS, it's flat at boost levels because MBT is not found and depending on the turbo you use, MBT will be at different engine speeds.
 

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is it possible to blow the motor running too conservative.

thanks for all the info. "you must spread some rep" blah blah.
Yes, too rich and too little timing will increase your exhaust gas temperature. But when I'm talking about being conservative, I'm talking about keeping the air/fuel ratios around 11.5:1 under boost and running about 2* below MBT.
 

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whats mbt?.....peak torque?

Yup, along the lines of it.. MBT - maximum brake torque, and should be based on the maximum torque produced at that certain RPM
 
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