Sub8

Hi guys. I have my 04 z06 back in UK we are able to easily fill up with 98 or even 100RON fuel. This would be equivalent to 95-97 Ron fuel in the US (the octane rating is calculated slight differently USA to europe).

As the LS6 would be considered to have quite a high compression ratio and its calibrated to run on 91RON fuel, i think there would be significant performance available by remapping the spark timing.

Anyone done this or know any figures?

Thanks.

TurboLX

100 RON is very similar to US "93 octane" (R+M)/2, so there should be no significant benefit to remapping the spark surface compared what one would run here stateside on premium fuel. Even the difference between 93 and 91 (US) octane isn't that big on a naturally aspirated engine. I would sleep better knowing I had some safety margin in the calibration anyway.

Sub8

Well that's a very sensible reply. Although with knock sensors you already have a bit of safety net?

romandian

do you know what timing the engie runs now?

Sub8

No idea. Engine has headers, some quite high lift cams (0.660) and polished throttle body. It has been tuned off course. I'm trying to decide if it's worth buying one of the tuning boxes to log and maybe modify further. Although being used primarily as a track car, reliability is important. After all it's not exactly slow with the current set-up!

romandian

get the "box", its fun. i would not expect any noticable power increases from more timing, however.

Sub8

No one got any dyno based torque Vs timing at fixed speed? Is the LS6 knock limited before MBT ? I`d be surprised if it is, at least upto peak torque RPM????