horrible detonation for no reason, can someone confirm my log and config?

[mdlimy]

My car detonates horribly at even low boost even after retarding timing all the way back to 7 degrees, and even with lambda around .76. The ignition map is what i ran on the same motor but with slightly higher compression, so i should be perfectly safe running it now with this lower compression motor. Plugs look lean all the time, even after i do a pull from 3k-4k with lambda around .76, it detonates at about 4k and i let off, plugs show signs of det and look lean. Brand new wideband sensor, also checked with my innovate wideband and it matched the vems.
You can see in the log near the beginning where i am at about 80% throttle from 3.5k-4k, right when i let off is when i started hearing detonation.
I cannot confirm that this is not an issue with my motor, i rebuilt the motor, ran it for about 200miles on the megasquirt but i never got on it hard enough to get this detonation, then i swapped to the vems, finished the break in, and started noticing it. So it could be an issue with my motor or it could be an issue with my tune, i would like to see if any of you could help me rule out the issue or rule out vems being the issue.
The motor is a volvo 5cyl 20v turbo, static compression is around 8.5:1.
The cylinders look clean, definetly do not look rich, infact nothing looks rich except the lambda meter...I tryed going even more rich to see if the detonation would go away just incase the wideband was reading incorrectly, once i got richer than .70 lambda i starting getting some cutout and stumbling apon acceleration, i assume from overfueling.

not sure if this is the correct section but i couldnt find one that seemed more appropriate. any help would incredibly greatly appreciated as i am at wits end with this issue.

Thanks
Robbie

https://sites.google.com/site/mdlimy/my-upload/v3.3_n003369-2011.05.25-17.48.46.vemslog?attredirects=0&d=1

[gunni]

Did you double check your primary trigger offset with a timing light?

It´s total 60deg now.

[gunni]

Here
http://www.vemssupport.com/forum/index.php?topic=1629.0

It´s actually 60deg + 6*6 = 60 + 36 = 96deg.

The "First trigger tooth" value is multiplied by the "Angular width of tooth" and then added to "TDC after the trigger" value to give you the total distance in degrees that the gap is from TDC.

This would indicate that your out by 36degrees, being more advanced that is.

[mattias]

With the "white" Volvo engines, at least the 5 and 6 cyl - never trust the "timing marks", they are not for ignition timing - only for assembling the engine and setting the cam and crank right. Make your own  TDC mark on the front of the engine as the stock markings are difficult to use for this purpose, at least make a temporary one that nearly touches the pulley. Then remove cyl 1 ignition plug, make a bracket with something that stops the piston 5 mm from the top. Turn the crank against this stop from both directions and make marks on the pulley - the real TDC mark on the pulley is right in between - this is very accurate and beats trying to measure the one spot at TDC where the piston is not moving as it can be still for several degrees. You can use a dial indicator to measure the piston depth too, not all that easy to mount though and you need an extension, and I think not as accurate as a dead stop where you eliminate mechanical play.

I have trigger settings for the 6 cyl engine that I trust with the most recent firmware (1.1.92), but not for the 5 cyl - at least no yet, maybe later this week we can compare.

[mdlimy]

Gunni, thank you very very much, you were dead right, i changed it to 96 and my problem went completly away =]

Mattias, for now it runs great, but i will defintly be making some timing marks like you said, i have plenty of these spare motors lying around so i can sort out all the angles and marks while being able to see the flywheel.

for now here is my current updated tune that works great, need to do some indepth tuning but now that at it doesnt detonate that shouldnt be hard 

https://sites.google.com/site/mdlimy/my-upload/june192011.vemscfg?attredirects=0&d=1

im pretty certain the 5cyl and 6cyl flywheels are identical, for what its worth.

thanks again guys, very happy to be able to start having some fun with this vems, looks like i will be picking up an e30 sometime this year for a turbo build, the fwd thing is getting boring, along with the volvo thing =p

Robbie