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Old 03-12-2015, 10:43 AM   #1
Pickler
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Default ignition timing how much is too much

On 09 2.5i NA I'm running 17-19* of timing at 700 rpm idle. On the fozy xt I am running 15-17* at 750* idle. These are all about 5-7* higher than stock values. I have also advanced timing in vacuum areas which the knock sensors are active (0.4+ g/rev). ie. 50* timing at 3200 rpm 0.5 g/rev vs 46* stock. The car feels much more responsive in part throttle driving or street driving. Is there a problem with running so much timing? I don't see knock from my learning table.
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Old 03-16-2015, 04:06 PM   #2
wgr73
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Do you have access to a dyno for a definitive answer? In your case I'd say too much timing is once you've passed MBT (since you aren't getting knock). You should be able to hold the car at that load on the dyno and test timing in the area.

Please correct me if I'm wrong.
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Old 03-16-2015, 06:46 PM   #3
Uncle Scotty
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yeah...gotta be careful....is it starting ok???
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Old 03-19-2015, 01:13 PM   #4
Bamofo
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If your playing with Cruise and Idle timing you will want to follow knock sum and not just feedback knock correction. if you want to use knock correct to watch it turn down the threshold so that it includes that cruising area..

knock sum is where i would start. Watch the number go up or go up to a certain point. On nonturbos i actually do something similar on the CVT cars where i force it to drop the IAM, so that fine correction can add enough timing to the point of knock then it backs off. back in 2012 i tuned my step mothers with this scheme and she still gets 35mpg all day on 93 octane. Non turbo. Motor has over 70k on it like that too.
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Old 07-07-2016, 12:25 AM   #5
Princev1r
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Default Timing and coolant temps?

Greetings NASIOC. Does having too much timing advance cause more heat for the engine? I was recently dyno-tuned(with a 3-port BCS) on a daily drive map, and sadly at 120k miles, I ended up having a rod knock on my STI as soon as we rolled off the dyno.

So yada yada yada, new short block, heads resurfaced, valve job yada yada yada. So I asked my tuner if it was safe to break in on the daily drive map, they said YES. So i drove a couple days on it, and man my coolant temps were ridiculously high.

Previously on my e-tune, I would run between 185-194F via the AP3. On my 3-port daily drive tune, I would run anywhere between 199-203F. I know that's not "that" high, but I was cruising 85mph with a very solid cooling system. I'm used to running 185-190F. Here's the catch I swapped out my 3-port and put the stock BCS back in, flashed into the married stock mode map, and tried the Cobb OTS stage 1. Both of those maps ran much cooler. So I'm holdin on the OTS 91ACN map for a margin of safety while breaking in.

Concluding question, does too much timing and less fuel constitute raising cylinder and head temps??? I'm not sure if this is all about making 30mpg on an STI. I know a hotter engine runs more economical, but not in the dead of hot SoCal weather. Thanks in advance.

Last edited by Princev1r; 07-07-2016 at 01:05 PM. Reason: Typo
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Old 07-08-2016, 09:41 AM   #6
86Dreams
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What is this? An
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Quote:
Originally Posted by Princev1r View Post
Greetings NASIOC. Does having too much timing advance cause more heat for the engine? I was recently dyno-tuned(with a 3-port BCS) on a daily drive map, and sadly at 120k miles, I ended up having a rod knock on my STI as soon as we rolled off the dyno.

So yada yada yada, new short block, heads resurfaced, valve job yada yada yada. So I asked my tuner if it was safe to break in on the daily drive map, they said YES. So i drove a couple days on it, and man my coolant temps were ridiculously high.

Previously on my e-tune, I would run between 185-194F via the AP3. On my 3-port daily drive tune, I would run anywhere between 199-203F. I know that's not "that" high, but I was cruising 85mph with a very solid cooling system. I'm used to running 185-190F. Here's the catch I swapped out my 3-port and put the stock BCS back in, flashed into the married stock mode map, and tried the Cobb OTS stage 1. Both of those maps ran much cooler. So I'm holdin on the OTS 91ACN map for a margin of safety while breaking in.

Concluding question, does too much timing and less fuel constitute raising cylinder and head temps??? I'm not sure if this is all about making 30mpg on an STI. I know a hotter engine runs more economical, but not in the dead of hot SoCal weather. Thanks in advance.
leaner mixtures burn hotter. Lean mixtures require MORE timing than rich mixtures. If your tuner is using less timing AND less fuel then yes it could be running hotter. A good tool is an EGT probe.

In this case the main mode of heat transfer is less cooled or still burning exhaust gas going through the turbo and the turbo heating the coolant, not the block heating the coolant.
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