I'm tuning a friends EVO8 old school BB FP Black but w/o surge ports / 2.0L / S2 / 110 leaded ....

When starting a pull from 2k rpms in any gear the car starts to accelerate then it feels like it pauses for a second before to boost kicks in and it takes off like a raped ape.

This happens in every gear, it feels almost like a full second of a stead state transition before rapidly building boost. The only config change from the last tuning session was a shift from HKS 272 to GSC S2 cams.

I tried trimming timing adding timing as well as fuel adjustments but there was no change in spool up behavior.

Any ideas on what would cause a dead spot in transition?

If you have messed with timing and fueling and have not noticed a difference, its most liekly mechanical, id check the wastegate and make sure its not loose or anything funky like that, and maybe a boost leak test

Mine used to do that, but it was the comp wheel hitting the housing. Turbo was toast. Hopefully your friend doesn't have that problem.

Good luck, brotha!

why no surge ports?

what boost level are you targeting?

would be good to see the boost vs rpm trace