I'm wanting to buy an Autometer tach and I eventually want to stroke my motor, but I don't want to buy 2 of their $250 tachs. So would I be ok with a 8K tach or should I get a 10K? Thanks. I'm thinking an 8K would be ok.

 

I would think 8K would be plenty! Is anyone spinning higher than that?? I recall reading something about 7,400 once. Then again, I'm running a blower so I'm limited by efficiency/impeller speed and I don't spin it higher than 6k or so.

 

If your spinning a stroker to 10g's on the street, your nuts. the 8 will be fine for any type of street motor you build. I thought the stock PCM can't handle anything over about 7g's. Am I wrong?

 

Stock PCM will limit you to 7K. Even with the best parts, turning 8,000+ would only be appropriate only for a race motor for a number of reasons. Longevity is the obvious one. But also very on point is that if the rest of the motor will support rpms that high, it will run like crap at normal street rpms.

Rich

 

With my FAST setup, we're turning the motor to 7200.
It's a 396 LT1 all forged on the bottle.

 

Thanks everyone for your input!

 

FWIW there are a few factory PCMs that are freaks for some reason. i had one of them on my old 95 Firebird, had no problem spinning 7600rpm repeatedly on the stock PCM. have also seen some that cut out as low as 6800 though

but yeah, unless you are building an all out NA race LT1, you will have no reason to go over 8,000rpm