I just took my 02 Z28 to the track today for the first time. I have 2:73 gears and a A4, the only mods I have done is a LS1 motorsports air lid and Magnaflow catback. The first run I shifted myself and in 2nd gear the rev limiter would kick in at 5,400 rpms or slightly below and car would sputter. I ran a 14.1....then I decided to let the car shift by itself in auto and ran a 13.7, after that I decided to try shifting again and ran a 13.5, but I shifted at 5,200 rpms and even caught a slight sputter there. Is this normal? I seemed like, just as the engine was reaching it's maximum h.p the rev limiter kicked in. Any suggestions? and is 13.5 good or bad for the A4 with 2:73's and the 2 mods I have done?

 

The guages are notorious for being inacurate. The only way to know for sure is to hook up an autotap system or equivalent and see what the actual RPM is when the limiter kicks. I'd say 13.5 is a pretty good time with 273's

 

The thing I'd be worrying about is, are you sure it's the limiter and not a very high rpm miss? In 2nd gear with 2.73s the tach should be fairly accurate by that point, if not then GM is really really bad.

 

hmmmm....i dont think the tach is that much off mines off by 200 at the beginning then it gets preety close...if i were u i would autotap it

 

On both my f bodies the tach was off by 300rpms, but that was 300rpms high. Still you probably just have an inaccurate tach.

 

The tach in my '98 was very close up top, but read a little fast at idle. The tach in my '01 reads a little slow at idle (~700-750), and in first gear never gets above 5700-5800 despite the 6600 rpm limiter.

Do not trust the gauges, use AutoTap.