Hello guys, I just recently bought a 93 z28 after getting rid of my foxbody and I must say that I am in love...but I am having a couple of problems which I am not sure of where to start looking. First my speedo is waaay off, it consistently is about 20-30mph off. How would I go about fixing this, I mean the car does not have gears or anything, it is a 93 m6 with 125,000 miles on it and it is completely stock down to the filter. Also the car starts to stutter when I take it past 75mph, my buddy who has done a lot of work to his lt1 says it could be my fuel filter but I was thinking it may be my opti because it is the original. I'm not really sure where to start because I have no experience with these motors other than a lot of lurking on this forum.

 

I would change the fuel filter first just because you have no idea when it was done. The stuttering should be more related to an rpm than a speed. I would ohm test your plug wires and pull the spark plugs and look at them before you jump straigh to the opti.

 

the speedo in a 1993 needs a box (dakota digital makes one) that calibrates the VSS pulses. You should only see this problem if you have a gear chane, whicj you say it dosent.

 

I will check into the gears thing with the guy I bought it from, but he claims it was all stock. Thanks for the help guys.