I succumbed to the temptation and installed a chip.....In the OBDII port.....I know pretty much the feelings about chips around here.....Mines different,yes it is!! So here is what I've found: Before chip. Going into 2nd gear would chirp a bit.....After install:Going into 2nd gear it moved the rear end around,got some real scratch caused me some concern. I loved it!.....Please don't tell me I must be smoking some real potent stuff cause I don't smoke....My Mark is a base with 143xxx on the speedo.It also seems (haven't really checked) to be getting better gas milage.....Understand folks I'm not trying to puff up chips just saying the one I have is a touch of magic.....Came with a 100% guarantee,don't like it,doesn't work? send it back for a full refund.....Bruce L. Hansen.....Senior Citizen (80)......Alive by the Grace of God