# Tuning questions **URL:** \ **Category:** Shift518 Automotive\ **Created:** [August 21, 2011, 1:48pm UTC](https://forums.speedlife.net/t/tuning-questions/260091 "2011-08-21T13:48:30Z")\ **Posts on this page:** 1\ **Showing post:** 4
**Author:** ![dsblk93gt](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@dsblk93gt](https://forums.speedlife.net/u/dsblk93gt)\ **Post date:** [August 21, 2011, 4:07pm UTC](https://forums.speedlife.net/t/tuning-questions/260091/4 "2011-08-21T16:07:12Z")
> [@When NOT to hyphenate names....](https://forums.speedlife.net/t/when-not-to-hyphenate-names/44802/13): > > :number1 I just ordered a book about it today. I understand firing when the valves are closed but it is still thought to be favorable in high performance apps because the time to fire off an injector decreases as the rpms start to climb. I also found that sequential systems that are used with a performance cam that has 220° of intake duration with. 050 valve lift can only inject ~ 60% of the fuel that a identical batch system can. Which basically means you need to run bigger injectors with a sequential setup in order to get the best fuel delivery. Are we talking aftermarket EFI or OEM efi systems? For WOT power I don’t believe sequential to have any benefits other than maybe individual cylinder control. --- _[View the full topic](https://forums.speedlife.net/t/tuning-questions/260091)._