ascMcLaren Enthusiasts

Hi all. I own an 86 Merc convertible in decent shape, but was underwhelmed about the performance. So I put on an 87 HO upper manifold with 70mm throttle body before I discovered the speed density FI isn't able to compensate for the extra fuel/air mixture. Now of course I have irregular idling. Before I reverse everything is there a trick to getting the ECU to recognize the performance upgrade? thanks

It should be okay with a 65MM but there are several people who can burn a new EPROM for you. Pete Campbell in Michigan is certainly qualified to do it.