93stallion302

I know that my speedo is off, because it used to be auto and now is 5-speed, but some1 told me that our stock tachs are off, reason I ask is that I notice that when im shifting at the track, it always bogs, not to bad, but it doesnt feel right. car has an aftermarket cam, and the advertised powerband is 2k-6k. im shifting between 5800 n 6k, could the stock tach be off n maybe im shifting to early?

speakerman86

from what I've been told, the stock tachs on the foxbodies could be off up to 10%. If you're taking it to the track often I would sure invest in an aftermarket tach to be sure

Joel5.0

Yup.... I've confirmed some them to show 300+ RPM at idle and 800+RPM on the top range. IOW.... people that swear their setup revs to 7000 RPM based on the stock tach, when they really are at 6000 RPM.

93stallion302

Yea thats why Im shifting at 6 and I might really be shifting at 5200, Ive got a 6AL on the car, i think imma try to hit the 6400rpm rev limit, thats the pill thats in it and see whre the stack tach reads when it hits it. Before i do that, doea any1 think thats is a bad idea.

lxman1

Does that override the stock ECm of 6250? The ecm has a built in limiter @ 6250 where it starts shutting down injectors.

93stallion302

Idk what that limiter does, cuz when my car was stock I hit 7k a few times by mistake. and Im not the only one, my buddies have done it too, as far as an overide, im pretty sure it doesnt since the ecu has never been touched, but i was under the impression these cars had no rev limiter.

FivePointOhh

didnt think our cars had one. i have an aftermarket tack and on my new set up i can peg 6500 like its nothin before i shift. makes solid power all the way up until i shift it. i'm just nervous to take it past 6500.

primetime5.0

there is a stock rev limiter of 6250

93stallion302

If thats true then our tachs are way off cuz on missed shifts I have seen the tach get to 7k and never heard anything that sounded like a rev limiter.

93stallion302

What does your aftermarket tach read when compared to your stock Tach?