thekellbeast
20+ Year Contributor
- 1,518
- 7
- Jun 28, 2003
-
Portland,
Maine
The longer runners are better for lower RPM's, but I don't know when you want to switch over. I don't know of anyone runing the JDM ecu, but there's a tech article (maybe it's a thread, I dunno) about making the switchover controlled by boost. I'm pretty sure that's the way the JDM ecu does it. Some people say it's better to controll it by rpm, because if you're in a higher rpm, but not building boost, you want the shorter, fatter, runners open. I don't have any personal experience though.

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