View Full Version : What to set my shift light to???
SSJoe15
12-02-2005, 02:16 PM
Hi i am new to both this forum and owning a ls1. I have been reading everyones posts for abut 2 months now. anywho i did the search thing and i had no luck fiinding a thread about what to set my shift light for on a M6. So what do you guys and gals think.
p.s. almost bone stock. (air lid and cat back exhaust)
thanks
BIG D's SS
12-02-2005, 02:34 PM
If it is stock I believe the stock rev limiter is 6200. I wouldn't turn it over 5200-5500. You take a chance of bending pushrods after that. My rev limiter is 6700 and my cam quits pulling at 6400. I have my shift light set at 6200. Gives me a little room for error before the cam runs out.
SLP00blueSS
12-02-2005, 03:48 PM
i have a stock internal ls1 and an m6 i set my shift light at 5800-6000. around town i keep is set at 5200 at the track i make it higher.
SSJoe15
12-02-2005, 04:29 PM
Great thanks for the responses. do you know what the rev limiter is set at from the factory?
Demonicbird00
12-09-2005, 07:20 AM
6200 from the factory
if your bone stock shift at 5800
i used to shift at 6k, but now im gonna be shifting at 6200 and my rev limiter is set to 6600
Stock Internals.
SSJoe15
12-10-2005, 10:25 AM
great, thanks for the info.
MadSeason
12-16-2005, 02:30 PM
With stock internarls to use torque across all your shifts you should shift at 5128, 4993, and 4908. Going over that is just waisting energy and over reving the engine. Unless you have a cam that changes the powerband you should be shifting here. Peak torque is only at 4400 RPM and you want to stay close to this when you shift back down
Demonicbird00
12-16-2005, 03:00 PM
il have to disagree w/ you.
i have bolt on and stock internals. my peak tq is at 4300 and holds till 4900.
my peak hp is at 5400 and hold till 6400 it doesnt drop.
tq gets you off the line and through 1st gear after that the hp comes in, since i have a flat line from 5400-6400 i shift at 6000 and it drops me back to 5500 and it stay up high, there is no tq there just hp to carry me through the traps
Demon_Speeding
12-16-2005, 04:42 PM
il have to disagree w/ you.
i have bolt on and stock internals. my peak tq is at 4300 and holds till 4900.
my peak hp is at 5400 and hold till 6400 it doesnt drop.
tq gets you off the line and through 1st gear after that the hp comes in, since i have a flat line from 5400-6400 i shift at 6000 and it drops me back to 5500 and it stay up high, there is no tq there just hp to carry me through the traps
:werd: The LS1's are best up high...So that's where I keep it when I'm racing.
No offense to MadSeason, I don't know him. I have PMed back and forth with DemonicBird and watched his progress...He's got a handle on the SI/bolt on cars.:yup:
MadSeason
12-16-2005, 06:33 PM
HP is derived from torque, you want to be at peak torque in the next gear when you upshift. just try it with consistency and you'll see times improve. its simple physics, once you maximize your shift points you will be one hell of a 6-speed master. Shifting at max hp works, but isn't the best possible way
MadSeason
12-16-2005, 06:42 PM
il have to disagree w/ you.
i have bolt on and stock internals. my peak tq is at 4300 and holds till 4900.
my peak hp is at 5400 and hold till 6400 it doesnt drop.
tq gets you off the line and through 1st gear after that the hp comes in, since i have a flat line from 5400-6400 i shift at 6000 and it drops me back to 5500 and it stay up high, there is no tq there just hp to carry me through the traps
you're shifting off your HP Curve, which is about 1000 rpms out of your peak torque, this puts you shifting outside of your powerband, when you're shifting your power is doing nothing but going downhill as far as acceleration. torque wins races HP just sells cars
Demonicbird00
12-17-2005, 12:41 AM
so what your saying is shift at 5k where my tq is at 349 but my hp at 310. when you shift your gonna drop about 500rpms that means im gonna be at 298 buy the time i upshift. Im sorry but thats loss of time and power,when im shifting at 6k my hp is staying at 343 at all times.
like i said tq is only gonna get you outta the hole after that its hp not tq
MadSeason
12-17-2005, 12:54 AM
where did you read this? "tq is only gonna get you outta the hole after that its hp not tq" it's just plain silly
Demonicbird00
12-17-2005, 10:14 AM
when your up in those rpms, tq is now irrevelant, most tq lines die after 5200 or so.
and all that is left is the hp to carry you through.
ill bet you if i or someone else were to run my/their car, w/ 2 passes. 1 pass shifting at your shift points, and the 2nd shifting at my shift points, my shift points will be .5 or more faster than yours
SSJoe15
12-17-2005, 12:06 PM
:shots:
How much does the rpm drop from gear to gear with a T56? What RPM is the RPM where peak hp is produced? thanks for all the responses, joe
MadSeason
12-17-2005, 01:03 PM
:shots:
How much does the rpm drop from gear to gear with a T56? What RPM is the RPM where peak hp is produced? thanks for all the responses, joe
Assuming 3.43 Gear and 26" tire diameter, peak torque of 4400 on completely bone stock 2000 ls1 peek torque will be higher with those running headers ect and people will need to shift later but not that much. I believe peak HP is at 5400 RPM
1st Shift 1696
2nd Shift 1346
3rd Shift 1133
This also assumes no RPM is lost in the shift, now just adding that loss of rpms to your peak torque as a shift point isn't exactly the optimum place to shift either
Think of when you shift to early, the engine bogs down to catch up, it's the same way when you shift to late. You may be in the power band but you're not getting enough Force (TQ) to the ground that you could be. The shift points I mentioned are calculated optimum. If you're a slow shifter plan on loosing at least 500RPM and add that onto your shift point or try powershifting.
When you're in that sweet spot getting pinned back to the seat. That isn't HP, it's TQ. It makes no sense at all to be shifting once the TQ the car can make falls beyond its optimum point. Reguardless if you're still making power for another 1000rpm it does you no good to shift back down that late, espically after your peak TQ. I'm going to try and explain this better using a dyno chart.
SSJoe15
12-17-2005, 01:29 PM
thanks. :burnout:
Demonicbird00
12-17-2005, 02:06 PM
yea i know that the tq puts you to the back of the seat.
but what im saying is that if you shift where your saying to, your gonna lose alot of time, cause your not using the motor to its potential
MadSeason
12-17-2005, 03:00 PM
http://edigras.iweb.bsu.edu/Public/shiftpts.jpg
Torque is what the motor is there for, why create more energy that's only going to be wasted and burned up as heat
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