I had the opportunity to scan in a Ferrari 348 aftermarket performance chip for Motronic 2.7 today. I'm going to do a bit more research before I name the firm and bash them publicly, as what I saw on my first glance must either be me making an error in my review or else a very, very bad chip was being sold to fchatters. Lets start with the hex file compare of the 3rd party aftermarket performance chip versus a stock Ferrari 348 Spider chip. The first 4k of code/data are identical. Copyright issues aside, that is actually a good thing compared to what is to come. At 4004h, however, we start to see the aftermarket chip make changes to Ferrari's programming code itself. Not to the fuel/air data, mind you (as would be typical on a modified chip), but to the code...and to my eye, not in a good way. Here's the original Ferrari assembly language subroutine: L3FFC: CJNE A,#005H,L4019 ;;;3FFC B4 05 1A ... CPL B.1 ;;;3FFF B2 F1 .. MOV DPTR,#L0162 ;;;4001 90 01 62 ..b MOVX A,@DPTR ;;;4004 E0 . MOV C,B.1 ;;;4005 A2 F1 .. Notice that at 4004h that Ferrari has an "E0" command (which means do a register memory MOVX operation). ...but the aftermarket chip changes that single "E0" command to "80" (an SJMP) which to me will cause a software error that will cascade until the Motronic watchdog timer kicks in. Now, the aftermarket chip doesn't change another byte of code or data after that one "E0" to "80" at 4004h until we get to 4604h...this address is in the middle of an existing Ferrari 8051 routine that starts as: L4600: MOV DPTR,#L649D ;;;4600 90 64 9D .d. MOV R1,#0AFH ;;;4603 79 AF y. MOV A,#003H ;;;4605 74 03 t. MOVX @R1,A ;;;4607 F3 . So instead of putting "AF" into R1, the aftermarket chip inserts "A1". At least this one small change doesn't scream out as an obvious software error waiting to be executed. The aftermarket chip leaves all of the rest of the original Ferrari program intact, save for changing the following 8 bytes: 00460D | 83 < F3 004804 | 80 < 98 004A04 | 00 < 75 004E04 | 00 < 08 004E0C | 80 < 93 004F0C | 00 < 75 004F0D | 80 < A0 004F0F | 80 < D2 Anyway, I'm going to investigate further to see if my initial thought (that the aftermarket changes to the OEM Ferrari program are in error and bad) is misguided. Perhaps a deeper analysis of the aftermarket program will reveal something that my superficial review missed. What I *expected* to see on the aftermarket chip was mere data being changed, such as the rev limiter, ignition timing, and a few fuel/air maps. I didn't expect to see ten bytes of Ferrari programming code changed (both code and data reside on our M2.7 chip). Also, the aftermarket chip *did* make changes to fuel maps on the chip, so I'll post a graph or two of those (what I would label "more traditional") changes later in this thread.