AFRs and Timing advance/retard
#61
Three Wheelin'
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One thing about the timing maps that have me wondering.
Why does Porsche and others drop the timing significantly
between 2120 and 3000 rpm. Thats before Boost is hitting.
Is it to increase EGT before boost in an effort to spool sooner ?
I see you have increased timing in that area
Why does Porsche and others drop the timing significantly
between 2120 and 3000 rpm. Thats before Boost is hitting.
Is it to increase EGT before boost in an effort to spool sooner ?
I see you have increased timing in that area
#63
Nordschleife Master
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One thing about the timing maps that have me wondering.
Why does Porsche and others drop the timing significantly
between 2120 and 3000 rpm. Thats before Boost is hitting.
Is it to increase EGT before boost in an effort to spool sooner ?
I see you have increased timing in that area
Why does Porsche and others drop the timing significantly
between 2120 and 3000 rpm. Thats before Boost is hitting.
Is it to increase EGT before boost in an effort to spool sooner ?
I see you have increased timing in that area
I'm in boost solid by 3000RPM, dip the timing a little to prevent knock, then increase again as the RPM rises..
Turbo spool starts at just over 2K on a stock car, and is at full boost by 3K...
#64
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Your WOT is WAY rich...BUT the reason I suggested disconnecting the O2 is I am willing to bet your entire map is too rich, but the computer is compensating for it until you hit 60% throttle and get into the WOT map...
#65
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The DMEs adjustment from O2 feedback is limited...
A boost leak will present itself as lean in vacuum and rich while in boost.
The factory timing map was developed with safety in mind. The factory has to assume that someone will put the car in 5th, and then floor it at 2000rpm. So the factory timing map reflects this.
Also, the stock AFM maxxes out at ~4.6v
-Rogue
A boost leak will present itself as lean in vacuum and rich while in boost.
The factory timing map was developed with safety in mind. The factory has to assume that someone will put the car in 5th, and then floor it at 2000rpm. So the factory timing map reflects this.
Also, the stock AFM maxxes out at ~4.6v
-Rogue
#66
Three Wheelin'
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Ok one thing at a time stock AFM 4.6 I see 4.59 so I'll leave the AFM alone.
Boost leak shows rich not lean?
Sooo... I can read the AF with the wide band, Zetronix multi gauge, I usually have it set for boost but I can set it for wide band AF and check the numbers. Disconnect N/B to take ecu out of loop.
How do I check for boost leaks, will carb spray work?
Boost leak shows rich not lean?
Sooo... I can read the AF with the wide band, Zetronix multi gauge, I usually have it set for boost but I can set it for wide band AF and check the numbers. Disconnect N/B to take ecu out of loop.
How do I check for boost leaks, will carb spray work?
#68
Three Wheelin'
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I goggled boost leak test so I got it need pressure in the system.
Awilson 40 asked a question about the timing between 2120 and 3000 rpm.
I'd like to know also.
Awilson 40 asked a question about the timing between 2120 and 3000 rpm.
I'd like to know also.
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#74
Nordschleife Master
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#75
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![Default](https://rennlist.com/forums/images/icons/icon1.gif)
One thing about the timing maps that have me wondering.
Why does Porsche and others drop the timing significantly
between 2120 and 3000 rpm. Thats before Boost is hitting.
Is it to increase EGT before boost in an effort to spool sooner ?
I see you have increased timing in that area
Why does Porsche and others drop the timing significantly
between 2120 and 3000 rpm. Thats before Boost is hitting.
Is it to increase EGT before boost in an effort to spool sooner ?
I see you have increased timing in that area
Dip in timing is to take account for the change in manifold pressure from - to +...
I'm in boost solid by 3000RPM, dip the timing a little to prevent knock, then increase again as the RPM rises..
Turbo spool starts at just over 2K on a stock car, and is at full boost by 3K...
I'm in boost solid by 3000RPM, dip the timing a little to prevent knock, then increase again as the RPM rises..
Turbo spool starts at just over 2K on a stock car, and is at full boost by 3K...