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· Premium Member
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Discussion Starter · #1 ·
Has anybody been able to measure what is the timing the stock ECU does at full throttle? The MKIV guys have measured this with an OBD-meter and it's 22-24 degrees, so quite alot if you are running pump fuel and lots of boost.

I was wondering what are the same values on the 7M-GTE and will lowering the base timing have an effect on the WOT timing?
 

· Madd Tyte JDM yo ®
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i doubt that the MK3 can get much more timing than the MKIV...

but under WOT and full boost w/ the abscence of detonation, its entirely feasible to see up to 27* of advance by redline. so far, that seems to be the norm that ive seen on cars.

Typically, timing curves take a dump as soon as you go WOT, and then the ECU typically advances timing as the RPM's increase, assuming there is no detonation. if its anything like mitsubishi motors, which the 2jz's seem to be from what youve mentioned, then its relatively predictable.

i think that the stock ECU will advance timing untill it sees knock according to its table. but im not sure if the stock ECU "KNOWS" or if its aware of what the final timing is when it does it. we are supposed to run a base of 10* BTDC, and the ECU advances from there. but... does the ECU just assume its 10* and blindly advance according to its tables? i dont think that the ecu is advance enough to be self-aware of its timing advance. im pretty sure that we should be able to pull base timing out to reduce total timing for incrased boost on pumpgas.

I personally had planned to reduce my base timing in an effort to reduce overall timing while using AFM scaling to tune fuel with raised boost on pumpgas runs.

i think our ECU is technically an OBD-0... plus, there is no readable bus port on the ecu for us to take readings from. i dont know if there is a way to read timing on the fly with any inductive pickup... if there is, we could watch timing on the fly. i have no idea on how to make a converter to make a readable output from an inductive coil on a plug wire.

i wish i had more solid info to give you...
 

· Moderator, l337 M0d3r4t0r
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13,222 Posts
It's hard to measure the hz, and actually know what is knock without the headset to listen for knock and log that on a standalone. I tried to map it with the Emanage but the timing table is all over the place and I don't believe the values as they go negative and crazy.

I bet something would be able to capture it some how like toyoobd1 but it's ultra slow the samples.
 

· Registered
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drj runs a motec?

that is a ALDL dash monitor from motec and that looks like info from an Mitsubishi evo car.
 

· when this baby hits 88mph
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2,200 Posts
X-man said:
Turns out the graph was from a Buick Grand National, but it was a Maft-pro.

Sean
yep that was indeed the tunerpro software from the maft pro. it was a screenshot i got from bob at fts from a turbo buick.
 
G

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I don't have stock ecu (megasquirt) but currently i'm running 23 degrees advance at WOT 6000rpm, but boost is (only) 1 bar.

I can post screen shot of my ignition advance table if you want to.
 

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Discussion Starter · #17 · (Edited)
drjonez said:
max timing is completely fuel and boost level dependent.

that said, if you're running 22+ degrees up top @ max boost (20+ PSI), time for a new engine....

So, care to enlighten some more?

ie. with stock turbo, what is the stock timing without any AFR corrections at 10psi or 15psi. What about with a bigger 60mm turbo at 15psi or 20psi?

Wether you need a new engine at 22+ degrees and 20psi or not depends the octane you are running or do you have water/meth injection. It's very doable.

How much does the timing go up if you correct the AFR leaner 10%? What about 20%?
 

· boost freak
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10,364 Posts
Krister said:
So, care to enlighten some more?
common practice on most standalones w/big turbos is 12-17....

Krister said:
ie. with stock turbo, what is the stock timing without any AFR corrections at 10psi or 15psi. What about with a bigger 60mm turbo at 15psi or 20psi?
great q. someone w/a MAFT pro running do some logging....

Krister said:
Wether you need a new engine at 22+ degrees and 20psi or not depends the octane you are running or do you have water/meth injection. It's very doable.
ok, then why ask this q?

Krister said:
How much does the timing go up if you correct the AFR leaner 10%? What about 20%?
same deal, someone w/a MAFT pro do some logging....
 

· Premium Member
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Discussion Starter · #19 ·
drjonez said:
ok, then why ask this q?



same deal, someone w/a MAFT pro do some logging....

Because I want to know and get a ball park of what kind of ignition timing does the stock ECU give out. I think its interesting info to say the least.

OK, so someone with MAFT Pro go do some logging... please :)
 
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