Thread: Road tune
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Old 08-29-2014, 07:15 AM   #35 (permalink)
bleunetizen
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alright.. back from another data logging.

increasing the knock threshold by 8000 did not increase timing at all, actually it did increase it by 1deg between 3200~3500rpm but i don't think that is significant enough. 8000 is more than 30% increase and it did not make any changes, I dont think this knock threshold adjustment is giving us much benefit.. if at all, or maybe it needs stupid amount? not sure how safe this can be though.


However, VVEL adjustment worked. Looks like it is running whatever is lower between VVEL B and C, you can see the log attached.

It did not increase the max VVEL timing value though, maybe its got something to do with the "valve clearance limit" table? apparently it is a safety feature to ensure the piston wont kiss the valves.

the MAF reading also seems slightly higher with the new VVEL timing, it was just a random increase I made to see whether it was gonna do anything or not.

So in short, while adjusting both VVEL B and C could not increase the MAX VVEL timing, it did make the correct changes as per the table in most areas, I think it is limited by some sort of safety mechanism. So there must be something to gain/lose from there.

It would be great if someone can share their 'tuned' VVEL timing so we can study it better..
Attached Images
File Type: jpg vvel.JPG (187.6 KB, 38 views)
File Type: jpg vvel2.JPG (85.5 KB, 26 views)
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