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beepbeep beepbeep is offline
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Join Date: Jun 2001
Location: Sweden
Posts: 5,564
Check following things:

1. Are you making boost?
2. Are there any leaks?
3. Is your AFR correct at full boost (need WBO2 for this, narrow-band doesn't work). Should be around 12.4-12.8
4. Is everything OK with cam timing? Your cam timing might be wrong...
5. Is ignition timing OK? Should be 26 deg at full boost. Now remember, what ECU says is 26 degrees doesn't have to be 26 degrees in real world, it only cares where trigger-wheel is. If your trigger wheel is offset, timing will be wrong.
6. Is turbo-impeller spinning freely?
7. Are there any obstacles in exhaust routing?
8. Is throttle opening completly?

Wastegate should not spew flames during full-power run. It can be made to spew flames on over-run (engine braking) as long as you don't zero the fuel cells at low-vacuum (=fuel cutoff). Otherwise, correctly tuned EFI engine will not spew flames can be made to do so (for fun?) by not engaging the fuel cut on engine brake. In that case injectors will still inject fuel into hot headers while throttle is closed, but this only happends on liftoff, never while on power.

My guess is that you either have cam timing issue, or ignition timing issues (your trigger-wheel might be installed incorrectly). You have to verify that zero degrees timing in your ECU really gives spark at zero degrees mechanically. The fact that your headers get very warm might point to very delayed ignition.

Good luck!


My internet connection is slow. I just read that you found out that ingition is culprit. I suggest getting a strob and making 100% sure that 0 degrees in software really is 0 degrees on engine. Even if it means by finding 0 degrees by mechanical means and making a new mark on a pulley. When you really know that mark is 0 deg, fire up the strob, set ignition at zero in software and see for yourself if it maches. If I understood your problem correctly, what your ECU believes is 0 degree is far from it.

I still fail to understand how your shop mapped the ECU car w/o noticing that something is completly wrong with ignition timing?? If they really mapped it on-dyno/using knock-headphones and hunted for max torque, they would surely go way past "sensible" numbers in ECU which would alarm them that ignition pickup is delivering false data. I'm not implying anything, but is there a posibility that they tuned it "by the ear" and just entered what they tought were "sensible ingition tables" into ECU w/o bothering to check it on dyno?

I just superimposed your two pulls and there is little doubt that your car reached 4000 RPM faster in second pull, implying more power.

Thank you for your time,

Last edited by beepbeep; 11-13-2007 at 06:00 AM..
Old 11-13-2007, 05:39 AM
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