Question Regarding Shifting
Thread Starter
Burning Brakes
Joined: Dec 2004
Posts: 882
Likes: 0
From: St. Augustine Fl
Question Regarding Shifting
OK, so im new to this dragracing stuff.
I dynoed my car and made max HP @ 5850 RPM now my car redlines at 6500, should I shift 5800 or wait till 6500?
I dynoed my car and made max HP @ 5850 RPM now my car redlines at 6500, should I shift 5800 or wait till 6500?
Le Mans Master
Joined: Sep 2004
Posts: 7,027
Likes: 6
From: Shiloh Ohio
Originally Posted by Dr.Ron
I'm thinking you should shift as close to redline as possible, without hitting the rev limiter.
That works good for me in C5's and C6's.It is not just the HP at the RPM in the gear you are shifting out of, you also need to consider what RPM you will be at when you engage the higher gear.
The closer to 6500 you get without hitting the rev limiter means you will be that much higher rpm after you shift.
CF Senior Member
Joined: Feb 2006
Posts: 23,313
Likes: 25
From: Tucson Arizona
I'm no expert but I don't think you just want to forego that last 700+ RPMs. As was mentioned, you want your RPMs up for your next gear and I would think you should still have some pull all the way to your shiftpoint.
My engine redlines at 6800 RPMs....I've been trying to shift at about 6500-6600 RPMs. You certainly don't want to hit the rev limiter but I think you want to 'approach' it.
My engine redlines at 6800 RPMs....I've been trying to shift at about 6500-6600 RPMs. You certainly don't want to hit the rev limiter but I think you want to 'approach' it.
Race Director
Joined: Aug 2000
Posts: 10,649
Likes: 31
From: Central Florida
There are two ways to determine optimal shift points.
(1) experimentation
(2) calculation
On a stock LS1/2/6/7, owners have been experimenting since CY 1996 and generally found that shifting right before the limiter brought best acceleration.
You can do the calculation of ideal shift points if you're curious or your car has significant mods. To do this you need to know your tranny ratios, your rwhp at 100 rpm increments between say 4400 rpm and the limiter setting (from a dyno run output in plain values rather than plotted on a curve).
Then you go to this shift point caculation guide
Ranger
(1) experimentation
(2) calculation
On a stock LS1/2/6/7, owners have been experimenting since CY 1996 and generally found that shifting right before the limiter brought best acceleration.
You can do the calculation of ideal shift points if you're curious or your car has significant mods. To do this you need to know your tranny ratios, your rwhp at 100 rpm increments between say 4400 rpm and the limiter setting (from a dyno run output in plain values rather than plotted on a curve).
Then you go to this shift point caculation guide
Ranger
