Iam

[iahtnoob]

I know that all cars don't act the same so what do you guys think about a tuner tuning a map where the IAM is set at 0.75? The car is running much better at that setting compared to 1.0 though. What are your thoughts?

[Spec B]

It makes no sense to tune that way (not even sure you can). Although IAM does a few things to protect the motor when it drops..all it really is a multiplier.

 

Tunes have 2 timing maps - a base and an advance. In its simplest form your base timing + (your advance timing * IAM) = total timing. So if your base is 20 degrees and your advance is 7 degrees X 1 (IAM) = total timing = 27. If IAM is reduced all it is really doing is reducing your advance. The tuner can easily reduce the advance from the getgo and leave IAM at 1.

 

If your IAM is anything less than 1..then you are knocking, it is not a tuning stategy.

[Th3Franz]

If the car runs better at IAM .75 instead of IAM 1.0, the car is knocking and pulling timing. Something is wrong with the car or the tune

[bmx045]

Almost sounds like the map is a limp map, or a "drive to tuner only" type

[iahtnoob]

Nope it's my final map. My learning view shows no knock and the A/F values are all within 5% plus my data logs are fine. I've done a vacuum leak test, boost leak test and all looks good. Who says the IAM needs to be 1? Is my ECU different somehow?

[m sprank]

WTF? LOL. Not sure if I should laugh or cry.

 

The above post needs to be moved to that "dumbest post ever" thread. Seriously.

 

Why does Ignition Advance Multiplier need to be at 1.0? Really?

[Spec B]

I suspect the map is set up to initially be .75 and then go up to 1 after a few miles.

[iahtnoob]

WTF? LOL. Not sure if I should laugh or cry.

 

The above post needs to be moved to that "dumbest post ever" thread. Seriously.

 

Why does Ignition Advance Multiplier need to be at 1.0? Really?

 

 

shut up dude, way to represent yourself as a vendor. You need to worry about your business and getting ALL customers their product. My tuner seems to think it doesn't have to be at 1. IAM continues to stay at 0.75 after several WOT and 600 miles of driving.

[SurlyOldManMN]

The map is jacked if it has to be knocked down 25%. It shouldn't need a multiplier like that...

[m sprank]

It needs to be at 1.

 

Plain and simple.

 

Why would you want your ECU to take the timing table you programmed and reduce the timing by 25% across the board? Why would you tune to this abnormality? Something is amiss. Could be as simple as a 1 second adjustment in the tune.

 

When someone asks why they want their ECU to multiply the given value by anything less than 1, I feel safe making a smart arse remark. Serioulsy. It is the interweb. Have a sense of humor. Re read your post. If it does not make a elementary school math student laugh...

[iahtnoob]

Thanks. I will have to keep an eye out with my LV's and logs.

[bmx045]

you should post up your map so we can really get to the bottom of it. note this is INITIAL IAM. it then goes up by 0.25

 

here's a stock 05 LGT MT map:

 

[iahtnoob]

PM coming to you BMX. Humor is great but sometimes it may cost you a customer so just watch what you type. Seems cut and dry that IAM should end up at 1 and there's something wrong with my car that I haven't discovered yet. Thanks for the input.

[m sprank]

There really is a thread that is the "stupidest posts ever" thread. That is not a joke. It exists here on this forum. I would not doubt that your post ends up there. I have never quoted any posts in said thread. But I ROFL when I read the updates. Sorry that humor has been had at your expense. But many posts contain quotes that live forever on the internet. You could always combat the humor and put the title of this thread in your sig.

[NSFW]

I know that all cars don't act the same so what do you guys think about a tuner tuning a map where the IAM is set at 0.75? The car is running much better at that setting compared to 1.0 though. What are your thoughts?

 

The tune doesn't really set IAM, it just sets the initial IAM. "Initial" meaning, "after reflashing and rebooting." If there is little or no knock, the ECU will increase IAM to 1.0 after you've been driving for a while.

 

If it doesn't increase to 1.0, something is wrong. That usually indicates that the tune was set up with more ignition advance than the engine can run without knocking. The ECU will periodically increase timing until knock happens, then it will back down, then it will increase until knock, and so on, until the tune gets fixed.

 

http://www.romraider.com/RomRaider/HowToUnderstandKnockControl

[Ridgeracer]

There really is a thread that is the "stupidest posts ever" thread. That is not a joke. It exists here on this forum. I would not doubt that your post ends up there. I have never quoted any posts in said thread. But I ROFL when I read the updates. Sorry that humor has been had at your expense. But many posts contain quotes that live forever on the internet. You could always combat the humor and put the title of this thread in your sig.

 

M sprank.....At one moment in time before some of us started learning about tuning, we would have more than likely asked the same question. Personally the OP had a ligitimate question if you consider that he probably doesn't understand how tuning works and what the ECM does with all those maps..

[iahtnoob]

Ridge is correct. It's okay, he's lost a customer here and so have those who are associated with him that have the ability to tune. He should probably spend all his energy dealing with Stromung.

[MasAyinde]

Unfortunately, it sounds like this guy was regurgitating what his tuner told him, and it's a shame if he's getting his car tuned by a "professional" who doesn't believe that the IAM needs to be 1. I can only imagine what else he is being told his car doesn't need. iahtnoob, you should post the name of the tuner who is telling you this.

[bmx045]

I think there is more to this story than we know.

[iahtnoob]

Mods can close this thread as I will not name the tuner and this thread will probably get out of hand and off topic. Thanks for the input guys.

[Th3Franz]

FWIW, sometimes false knock from a clutch can prevent the IAM from going up. The car seems especially sensitive immediately after a reflash. My tune is set up to start at .9 and then go up to 1. Occasionally it has stayed at .9 for a while because I wasn't smooth enough on the clutch with the reduced timing after a reflash. Saw it in my logger, reset the ECU, paid more attention the next go and all is fine.

[rtbrjason]

I've heard of tuners that tune like this. I believe Gabedude has some tunes setup this way. It runs at .75 IAM unless using a superior fuel that will allow the IAM to raise to 1 and add a degree or 2 of timing globally. I don't really see anything wrong with it, but everyone is trained to believe that IAM has to be 1 so everyone will assume this tune is garbage.

 

Either trust your tuner or don't.

[m sprank]

Exactly. This qoute is not valid

M sprank.....At one moment in time before some of us started learning about tuning, we would have more than likely asked the same question. Personally the OP had a ligitimate question if you consider that he probably doesn't understand how tuning works and what the ECM does with all those maps..

as the OPs first post states his tuner said it was fine. So, he knows enough and already has "professional assistance".

 

I dont tune. Shamar does. But read the entire thread. It is also not may fault there is a thread that catalogs "humorous" posts. Dont shoot the messenger.

 

False knock can come from many things. Subarus are notorious for shift knock. I personally had a set of Perrin front endlinks that caused false knock in the two cars I tried them in.

[NSFW]

I don't really see anything wrong with it

 

Consider this:

 

If it doesn't increase to 1.0 [...] That usually indicates that the tune was set up with more ignition advance than the engine can run without knocking. The ECU will periodically increase timing until knock happens, then it will back down, then it will increase until knock, and so on. [...]

 

So your ECU is going to periodically force the motor to knock. The only thing that keeps IAM at less than 1.0 is the fact that the ECU periodically adds timing, causes knock, retards timing to safe level, and tries again later.

 

What are the long term consequences of forcing an EJ25T to knock on a regular basis? I don't know, but I'm not willing to be my motor on the theory that there are none.

[bmx045]

Thanks for breaking this down NSFW. There are things here we don't know about this situation, what if the gas was bad during the tune? What if the engine's shape was less than stellar?

 

If the mechanical condition of the engine isn't perfect during the tune, the open source tune will reflect it- the tuner should ERR on the side of caution rather than performance- especially with an engine that continually knocks. There's only so much a tuner can do at the time of tuning- and one of them is to NOT cause the ECU to blow the engine up (by way of trying to advance timing and then knocking time after time)