# Halloween Dyno Day at C&C MotorSports **URL:** \ **Category:** Shift518 Automotive\ **Created:** [October 5, 2009, 6:51pm UTC](https://forums.speedlife.net/t/halloween-dyno-day-at-c-c-motorsports/247339 "2009-10-05T18:51:35Z")\ **Posts on this page:** 1\ **Showing post:** 187
**Author:** ![SSmokinn\_SS](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@SSmokinn\_SS](https://forums.speedlife.net/u/SSmokinn_SS)\ **Post date:** [October 31, 2009, 10:17pm UTC](https://forums.speedlife.net/t/halloween-dyno-day-at-c-c-motorsports/247339/187 "2009-10-31T22:17:06Z")
> [@Did we Land on the moon?](https://forums.speedlife.net/t/did-we-land-on-the-moon/25172/16): > > We are probably on the winter blend of gasoline now. Its slightly lower octane. Your tune is for the summer blend and a custom tune is more sensitive to this subtle difference. You may be picking up some KR and the PCM has adjusted timing advance and fuel trims to compensate. Its just a thought. It doesent explain why every one else had near the same numbers but every car/engine/PCM is different… as im sure you know, LSx cars have a low octane timing table and a High octane timing table which switches back and forth according to the octane rating (87 low, 93 high) well, my Low octane and High octane tables are the same for easier tuning reasons. IF the gas is on a winter mix like you claim, then my car for sure would pick up some KR sense the only thing it knows to go by is 93+ octane. --- _[View the full topic](https://forums.speedlife.net/t/halloween-dyno-day-at-c-c-motorsports/247339)._