SEAT IBIZA GT TDI 110hp

'I recently bought a Seat Ibiza GT TDI with 110 horsepower. It has an additional control unit from FS Motoren Technik Köln (has anyone heard of them?). It's supposed to have a power output of 130 horsepower. I'm looking for other ways to increase the performance, possibly a different, better control unit. Do you have any suggestions? Currently, the car, according to the speedometer, reaches a good 210 km/h on a straight road, accelerates quite well, and doesn't smoke or produce excessive soot during acceleration, unlike other 'chipped' TDIs!' 'Because there are so many unreliable companies in the chip tuning industry, I'm a bit cautious.'
THX
Monchi

Hi.

"Why don't you do a dyno test with the car, both with and without the tuning (by disabling or removing the power box)? This will give you a rough idea of the tuning's effectiveness."

If the result is 30 extra horsepower or more, I would advise against trying to get "even more."
With less demand, I would crank up the production volume to around that limit.

Other modifications (besides, of course, a turbocharger) usually don't yield much improvement, or the effort involved doesn't justify the horsepower gain.

Okay, mine is supposedly doing just under 220 km/h according to the speedometer on a straight road, but it's supposed to be stock. But honestly, I'm starting to doubt that. By the way, the shaking/jerking is gone since I topped up the oil. The warning light came on shortly after I posted about it in the forum. I'll do a top speed test as soon as the weather is better, but the 0-100 km/h interval is already displayed, so I'll look into that as well.