Thread: What RPM should I set my tack light & rev limiter to???

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....When on the Flywheel Dyno my small block Chev's. maximum HP was @ 5400 RPM. What would be a good RPM to set the Tack shift light at??? Should I wind it past it's maximum HP??? Plus what RPM should I set the rev limiter at??? Right now I have a 5400 chip in the tack light & a 5600 chip in the rev limiter. But I can't seem to shift fast enough when I see the light to shift before the rev limiter cuts the motor off!!! {maybe I don't have the reflexes of an 18 years old anymore?}.... THANKS Bill

I would try 5200 on the light and 5600 on the rev limiter. You say max hp is at 5400 . When the light comes on when you shift you should be at 5400. The rev limiter is not even a concern when shifting. Its there to protect your engine if some thing goes wrong. I would be comfortable with the rev limiter being at 5600-5800, you just dont really want to be spinning it over 6000. This is where I would start ,when you run it down the track you can fine tune...

.....THANKS Denny & Big Truck Driver, I'll put in lower RPM chips tomorrow....
The only concern I have with the rev limiter chip is I don't want it so close to the tach light chip that the engine shuts down every time I shift. 400 should be a big enough spread, I know that 200 isn't!!! Bill

Rule of thumb I've heard and go by is shift 10% higher than peak HP (5900-6000) I would redline it around 6400 unless your valve train isn't up for it (hydraulic?)... Try adjusting your shift point in 100rpm increments and let your time slip tell you where you want to be... better to err on the short side especially for 1-2 shift for best ET.

Better than the rule of thumb: where does it stop pulling?

-Chris

Originally Posted by skids72

Rule of thumb I've heard and go by is shift 10% higher than peak HP (5900-6000) I would redline it around 6400 unless your valve train isn't up for it (hydraulic?)... Try adjusting your shift point in 100rpm increments and let your time slip tell you where you want to be... better to err on the short side especially for 1-2 shift for best ET.

Better than the rule of thumb: where does it stop pulling?

-Chris

What Chris say's here is what I try and tell people.