I am so amazed, I wasn't expecting much out of the headers, except a big pain in my body after crawling under the car to install them.
Took me and Bobby 4 hours to install them, because plenty of bolts were rusted.
The car is now really fast, and the accelerations are smoother. Way smoother...
The idle is smoother too, but climbing a dropping a bit, I guess I have to reset the computer.
I am so pleased with the result, but I won't do it on another car if I am not paid to do it hahaha.... What a pain.
This is the best upgrade after the chip.
'89 535i RD springs, headers, rims.