Birdie75

Original Tune:

EJ205 WRX , stock internals, manual boost controller, VF24 turbo, aftermarket exhaust manifold, up pipe, bell mouth down pipe with a Fujitsubo cat back exhaust. Achieved 298hp @ wheels on 17psi.

Not long after that the turbo died so i replaced it with a VF23 (VF24 no longer available) and I removed the cat and restrictor pipe and replaced them with a 100cpsi cat only.

Time passed and I had a little front end accident (didn't stop in time when a rear ender happened in front of me).

On collecting the car she backfired 30secs up the road quite loudly and again 5mins later, still backfires often but not as bad, vacuum is now at 20psi but used to sit st 15, feels a bit sluggish but i haven't been thrashing it since replacing the turbo as it wasn't re-tuned and I wanted to upgrade the injectors and fuel pump first and had the intercooler pipes modified and shortened in the mean time.

Current Tune with VF23 turbo, Sti injectors, and Walbro 342 fuel pump and an EBC.
270hp @ wheels on 18psi ???

I've dropped 30hp and my tuner is absolutely stumped as to why, no fault codes were found, he strongly believed the timing was out (as did an engine rebuilder when he heard the car idling at his workshop, said it sounded too smooth for a Subi) and maybe jumped a tooth or the timing belt was put back on incorrectly by the mechanics when the rear timing cover was replaced.

He's checked everything from cam marks (twice) and crank marks and even counted every tooth on the belt, got the cam specs to check the TDC, pressure loss from the FMIC, pressure tested all pistons with an average of 160psi, inspected the cat and done a run straight out of the dump pipe just in case  (lost power), called a few tuner mates as well and anything they've suggested he's already checked.
The car runs fine, no spluttering, no hesitation, starts easy just less power than before.

He's been tuning cars for 15 years and seems quite knowledgeable and passionate about his work but this job has him scratching his head.

I'm nearly 2 grand out of pocket for all the checking and Dyno runs he's had to do and I'm still down on horses with no explanation as to why !!.