anyone ever topped out a 1999 firebird formula with a ls1?
Unless you have bypassed the computer controls it cannot be done as it will go into fuel cut at around 5000 rpm's. To test if your system is still active race up the car in park or nuetral and see what happens at that RPM ...
I did have a 1996 Formula with an LT1 and had my buddy at a GM dealer reflash the PCM wich basically cut off the speed and rev limiter, Anyway I did get it easly to 144mph and feel it could have done better but my brave got up and went at that speed.
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