SHIFT POINTS

[06 roush]

what are you guys pushing your cars to rpm wise ? i have my shift light set at 6600 . what about you ? just wondering

 

[steedman07]

I have an auto, but my shift points are set depending on when horsepower starts dropping.....Have you gotten ur car a custom dyno tune? I would do that if possible before setting ur shift point to a number..ur power may be dropping off before u are shifting.just a thought for ya..

 

[stangdude2000]

Where exactly is the ideal shift point when looking at a dyno graph? Seems to me it should be somewhere once it starts dropping off, but at an rpm where once you do shift, the power doesn't drop further...
Random example: Peak 300 HP is at 6200 rpm. 6500rpm = 280 hp. You shift, that drops it to say 4000 rpm where there is 240 hp on tap. Next scenario 6600 = 270 hp. You shift and that brings it to 4200 rpm where there is 270 hp on tap.
In this case, wouldn't 6600rpm be the ideal shift point since you are always generating as much power as possible? Or is there another factor I am overlooking?

 

[CRoberts91]

stangdude, i would say you have this right. as long as you are i.e. leaving 3rd while you still have decent power and you shift in to 4th with an equal amount i'd say thats the optimum shift point. i need to dyno mine so i can figure this out, i need an x-cal 3 too so i can adjust this. and by the way, how far can i push my revs before it gets dangerous?

 

[Five Oh Brian]

Ah, the beauty of a big stall converter in my 07 GT. I shift at 6500 rpm's. With peak torque coming on around 4500 rpm's and having a stall converter that flashes to 4300 rpm's, I am never below 4300 rpm's when shifting, so the car is always in the best part of its powerband (between 4300 and 6500 rpm's).

 

[CBus 06 GT]

Where exactly is the ideal shift point when looking at a dyno graph? Seems to me it should be somewhere once it starts dropping off, but at an rpm where once you do shift, the power doesn't drop further...
Random example: Peak 300 HP is at 6200 rpm. 6500rpm = 280 hp. You shift, that drops it to say 4000 rpm where there is 240 hp on tap. Next scenario 6600 = 270 hp. You shift and that brings it to 4200 rpm where there is 270 hp on tap.
In this case, wouldn't 6600rpm be the ideal shift point since you are always generating as much power as possible? Or is there another factor I am overlooking?

That pretty much sums up what I've heard. The shift point is determined by where at in the power curve you'll be once you're in the next higher gear. The key is to know how much RPM drop you'll have between gears. From 1st-2nd, you'll have a bigger RPM drop than the 3rd-4th gear change since the spread between gears gets tighter as you go through the pattern, so your shift point in 1st will not necessarily be the same as in 3rd.