Quarter Mile Shift RPM

[Hammer]

What RPM's do you shift at for best 1/4 mile times? I have shifted at about 6500 in the past and am curious if 6000 might give a better time. I am going this weekend and thought I would throw this out fot the H of it.

[Aurora40]

Right before it hits the limiter. The car doesn't drop power much even stock, so it's making more power at the limit than it will wherever the revs drop to after the shift.

[Hammer]

That's about what I been doing. Like I said, thought I would throw this out and see.

Thanks for the reply.

Originally Posted by Aurora40

Right before it hits the limiter. The car doesn't drop power much even stock, so it's making more power at the limit than it will wherever the revs drop to after the shift.

The car loses significant power in the top end unless you have headers and porting. Only then will you acheive that flat power band at the top.

[rkreigh]

run a dyno, see on the power curve where the power starts to "tail off"

if you shift way past the peak, as jeff mentioned, the car will slow down. on the stock cars often the power peak is around 6300, so shifting at 7k is going to make the car run slower. rear gears have alot to do with shift points too. with the stock gears you are pulling 3rd through the traps.

[Hammer]

I do pull third at about 6500 through the traps. I will post more after this weekend. Thanks for the inputs fellas.

[blackjack]

when the car is geared properly,you should be able to shift at peak horsepower,and the engine should come down close to its maximum torque in the next gear.
bj
91/1735

[Aurora40]

Originally Posted by Jeffvette

The car loses significant power in the top end unless you have headers and porting. Only then will you acheive that flat power band at the top.

Huh. I never dyno'd mine stock. The most-stock was with just a ported top end and stock manifolds/exhaust. It dropped off after about 6,200 rpm, but not very badly. I just figured stock would drop off more, but probably not tons more. Then again, I did find myself hitting the rev limiter a lot when I first put the ported top end on because it kept pulling vs dropping off.

Still, on the 1-2 shift (at 7,000 in 1st) I think the revs will drop to ~4,700 rpm. So as long as it doesn't drop that bad I'd still think you are better off running it to the limiter.

Most stock cars at a 7K shift are back down to around 300 hp. and when you shift you are dropping the car back on the wrong spot of the power curve. You want to be hitting the curve where you are making the most power.

[Demps]

Originally Posted by Hammer

What RPM's do you shift at for best 1/4 mile times? I have shifted at about 6500 in the past and am curious if 6000 might give a better time. I am going this weekend and thought I would throw this out fot the H of it.

Let the skinny guy down the road show you Ted