Immobilizer lol... E30 lol...
There might be a string and twig type immobilizer, thats as advanced as it gets.
If you have a 16 button OBC, theres a code feature, I believe the car won't start if thats enabled.
91 318is - M50NV (gone)
02 WRB Subaru WRX EJ207 forged, 320 AWHP stock turbo.
85 - 325
02 325i Sedan