Do these two buttons really make a difference.
In estimating my fuel consumption , i filled the tank and drove till gas warning came on.
under normal shift. approx 400 km.

did the same thing , filled tank (till hose shut off) chose performance shift and got almost 100 km less.

same basic driving, back and forth from work , occasional trip round town no long distance very little highway..

i will leave it on normal shift ,,just for the mileage because i cant believe i got soo much less mileage on performance shift.

Stock it should only be a difference at WOT of about a 200rpm difference from where normal shift occurs.

Most can't notice the difference.

It seems to make quite a difference on my 92, part and full throttle.

According to my tach, Normal at WOT is 5000-5100, and Performance shift is 5200-5300. I think 5300 is the max shift point.

For 91-93 L67'*, yes. 94/95 shift a tad higher (which is what the topic author has).