I’m getting a weird issue out of nowhere the motor is not out of time the compression is 150 on all 4 cylinders cranks over normal until it goes to fire then the starter struggles to turn it over and pushes air thru the intake I have the Hondata crp kit and I’m using s300 v3 same tune as when it was running fine

 

Any help it slows down the cranking when it hits and then backfires could it be a ignition issue if it’s firing at the wrong time

 

Should double check your timing belt, check it's tension and set it to TDC for cyl #1 and make sure it didn't skip teeth on the cam/cams checking the alignment marks.

 

I re timed it just be sure I think it’s the Hondata cop box firing all cylinders at once