Benny-4000 Member 31 Member For: 16y 9m 15d Posted 09/03/16 07:37 PM Share Posted 09/03/16 07:37 PM I have noticed that there is significant differences in ignition timing between a standard 2007 F6 BF and a standard 2009 F6 FG. The load scales are different, but the FG igntion table is quite a bit more advanced in most areas of the table. Given that the FG F6 runs slightly higher boost than the BF F6, I would have thought that if anything the F6 FG would have had less ignition advance than the BF. It looks to me like the the F6 FG assumes a higher octane rating in the borderline knock table (ie 98RON fuel), will pull the timing back through knock retard if 91RON or 95RON is used and will recover the timing back to the borderline knock table if 98RON is used afterwards. Is there is a difference between the F6 BF & F6 FG engines that allows this timing increase while still keeping a conservative timing table? Or is the F6 FG ignition tables just optimised to take better advantage of 98RON than the F6 BF? Link to comment Share on other sites More sharing options...
Ralph Wiggum Moar Powar Babeh Lifetime Members 19,323 Member For: 19y 2m 7d Gender: Male Location: Perth Posted 09/03/16 11:23 PM Share Posted 09/03/16 11:23 PM " The compression ratio has been reduced from 8.7:1 to 8.47:1 to allow optimum compromise between turbo boost and spark timing, resulting in improved overall engine efficiency and driveability. " 1 Link to comment Share on other sites More sharing options...
Ralph Wiggum Moar Powar Babeh Lifetime Members 19,323 Member For: 19y 2m 7d Gender: Male Location: Perth Posted 09/03/16 11:25 PM Share Posted 09/03/16 11:25 PM Just now, Ralph Wiggum said: " The compression ratio has been reduced from 8.7:1 to 8.47:1 to allow optimum compromise between turbo boost and spark timing, resulting in improved overall engine efficiency and driveability. " ^Applicable to FG F6 Just now, Ralph Wiggum said: Link to comment Share on other sites More sharing options...
Benny-4000 Member 31 Member For: 16y 9m 15d Posted 10/03/16 06:59 AM Author Share Posted 10/03/16 06:59 AM ah huh, thank you Link to comment Share on other sites More sharing options...
Ralph Wiggum Moar Powar Babeh Lifetime Members 19,323 Member For: 19y 2m 7d Gender: Male Location: Perth Posted 10/03/16 07:11 AM Share Posted 10/03/16 07:11 AM No worries, good to see someone reading the tables well enough to notice something like that. Are you on the HPT forum? Link to comment Share on other sites More sharing options...
FiftyOne Bronze Donating Members 1,145 Member For: 11y 4m 29d Gender: Male Posted 10/03/16 08:55 AM Share Posted 10/03/16 08:55 AM Different sizes in turbo, plus emissions, probably most likely the cause Link to comment Share on other sites More sharing options...
Ralph Wiggum Moar Powar Babeh Lifetime Members 19,323 Member For: 19y 2m 7d Gender: Male Location: Perth Posted 10/03/16 08:58 AM Share Posted 10/03/16 08:58 AM BF/FG F6 have the same sized turbo. Link to comment Share on other sites More sharing options...
FiftyOne Bronze Donating Members 1,145 Member For: 11y 4m 29d Gender: Male Posted 10/03/16 09:02 AM Share Posted 10/03/16 09:02 AM I could be wrong, I thought they where different? Happy to be proven wrong however Link to comment Share on other sites More sharing options...
velocityxr6t Member 122 Member For: 16y 17d Gender: Male Posted 10/03/16 09:07 AM Share Posted 10/03/16 09:07 AM Fg xr6t only has the smaller turbo. F6 is the same. Link to comment Share on other sites More sharing options...
Ralph Wiggum Moar Powar Babeh Lifetime Members 19,323 Member For: 19y 2m 7d Gender: Male Location: Perth Posted 10/03/16 09:08 AM Share Posted 10/03/16 09:08 AM 5 minutes ago, FiftyOne said: I could be wrong, I thought they where different? Happy to be proven wrong however You are wrong #proven 6 Link to comment Share on other sites More sharing options...
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