Spool up on my new EFR8374 isn’t too bad. Given this is a 79lb/min turbo (similar to a GTX35R), it is certainly acceptable. It doesn’t feel that much laggier then the 7670 I ran before. This is 3rd gear, Internal wastegate, 2.5L with Cosworth heads and cams, E85. Peak injector duty cycle was 69%. [ID2000s] Time to turn it up to 35psi.