1ScrudeDude

Ok, some of you will think this is a newbie question, but I don't make it a habit of hitting my rev limiter! (So I wouldn't know, until maybe now.)

Yesterday, I was going WOT in 2nd, and just before I shifted into 3rd, the engine "sputtered" and popping sounds came out exhaust. I was watching my tach, and I was only at 6500 rpm (cammed car, limit at 6800rpm) when I shifted.

Is the stock tach that inaccurate (if at all)? How much? Will it show higher or lower than the engine spin?

I just had a full tune completed and everything was dialed in and I haven't done anything else to the motor.

foff667

iTrader: (2)

it very well can be off by that much sound limilar to hitting the rev limiter did you compensate for tire size and gearing when you had it tuned? not sure how you can check other than revving in neutral to 6500 but i wouldnt advise that lol.

1ScrudeDude

Yup, 4.10s and stock tires were plugged in.

And I agree, 'not too crazy about trying to hit it again, neutral or on the road. Thanks.

Cricket99SS

The stock tach isn't as much inaccurate as it is SLOW. I can be hitting the rev limiter in first gear when the tach shows 600 rpm less than what the limiter is. First gear it is the worst because the engine RPM raises so quickly, then it's a little better in 2nd, and in 3rd I can usually go by what the tach is reading.

Best thing to do besides getting an aftermarket tach is getting a shiftlight put into one of your air vents.

Colonel

The stock tach is a joke. I only look at it when I'm doing my burnout. Raise the rev limiter and try again.

Slowhawk

iTrader: (12)

I agree.My rev limiter is set to 6800 and I hit it daily.(that's what it's there for)
My 1-2 shift is at 5400 ,2-3 shift is 6000 as indicated on the stock tach.Anything over that is the rev limiter.

2002_TAWS6

Good... I thought I was just imagining this on my car.

My Rev limiter is set at 6600 and I have to shift at 6400. What a joke. Maybe its time for a harlan shiftlight. Would that work any better than the stock rpm guage? or are they linked together?

One thing for sure is im not getting those big a$$ rpm guages.

Colonel

Harlan's light is not linked to the tach. It will come on when it is supposed to, not when the tach says it should.

Jabroni

The light works real well. As Colonel said, it comes on when the PCM sends the tach signal corresponding to the programmed tach value. You'll never look at the tach again!

1ScrudeDude

Thanks Colonel and everyone. It's making sense to me now. The reply that said that the stock tach is "slow" (among other things) is dead nuts.

We had a cold snap down here in FL and the LS1 shoots into the red unbelievably fast when it cools down (low 60's, no humidity.) The 4.10 gears expedite this phenomenom.

This car typically runs in the summer for 6 months when it is 90 degrees with 90% humidity, which I hate.

It looks like a shift light for me! Thanks again y'all!