Mainly this is because losses are greater at higher rotational speeds and there is more resistance to acceleration at higher speeds (for obvious reasons). Also, the space between the gears are not exactly even.

On a circuit, the shifting point is different for sure. You short-shift (at lower rev than 'usual') some times and sometimes you use a few more revs than you 'should' depending on what the car is doing. I mean, you don't want to change from 3rd to 4th just to brake again like a quarter of a second afterwards. Equally, there are times when you'd rather not change gears in the middle of a corner. Obviously the ideal situation situation here is to get your gear ratios to match the track, but that's a whole different game altogether...

 

Thanks for the replies.


I've come to the conclusion that Shifting beyond 7k is not optimal in every gear. But in the case of Drag racing Shifting past 7K in 4rth might help since I dont have to shift gears to 5th when crossing the finish line.

 

It's not so much when you shift but how low the rpms drop after you shift. You want to shift high enough that you fall into a range where you're making power already on the bottom of the next gear. If you shift too early, you have to build boost back up and waste time.
By going too high, you might be losing power up top but you're making alot of power down low after you shift. If you shift too early, you were making good power when you shifted but lost it on the bottom and have to build it back up.

 

Ah you speak the truth

 

Seems like it helps to watch the Tach as much as the boost gauge. Always wanna keep the motor in its powerband, to get the most out of it. I had trouble with that type of change too being that i came from driving an Eg6, with a built Type R inside. Seat time is the key. Figure out what works best for you, and the current state of mods on the vehicle.

Not only that, but try stuff. what works for one person, may not work for another. You'll get it.

 

it is normal and most people with flashes in my area from dynoflash or one of the other companys shift around 7.6 if it wasn't safe to shift that high dont you think they drop the rev limiter down from 8k???

 

I dont know about some of you but my car only has an exhaust on it and it pulls all the way to 7800 rpms. IN my srt you knew when you were coming to redline cause the motor FELT like it was running out of breath

 

If you factor in gear ratios, and torque multiplication and such...How much power is making it to the wheels at 7800 rpm in 2nd gear vs. @4000(Wild guess as to where it would actually land) in 3rd?

 

what rpm should hks 280/280 shift at on stock turbo

 

~7200rpm.Stock turbo is the restriction.Stock turbo blew hot air after 7200rpm.

 

At what psi? How much airflow? Are you sure the IC isn't the restriction?