N/A Timeslips
- Thread starter blaktoutprobe
- Start date
i gotta get to the track one of these days....
hey i have a question..is it really safe to shift past 6500? just as long as you dont take it all the way? i have a tendency to shift around 5700-6000 just outta habit, so id be afraid of waiting until 6500 to shift.....
hey i have a question..is it really safe to shift past 6500? just as long as you dont take it all the way? i have a tendency to shift around 5700-6000 just outta habit, so id be afraid of waiting until 6500 to shift.....
your reaction time doesn't affect your 1/4 mile time. you can wait 5secs if you want and you'll still run a 16 ... the only time it really matters is during a competition and/or bracket racing. But to get a better r/t, don't launch when you see the green light because by the time your engine transfers the power to your tires and that your tires stop spinning, you lost 0.6 or something like that. Launch when you see the last yellow light. getting a sub 0.1 r/t takes lots of practice =)topher said:
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
you're best off going to 6500 at every shift when racing
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
yup - and also dont forget the torque multiplying effect of the gearbox too 
another tip for drag racing - lower your tyre pressures to 15psi. you will get better 60ft times because the tyre (certainly not as much as proper drag slicks) stays on the road but the wheel has already started to move. then all of a sudden (mind you this is incredibly quick) the tyre gives you a sling-shot effect start.
my best 60ft was 2.142 which is great for a fwd street car!
another tip for drag racing - lower your tyre pressures to 15psi. you will get better 60ft times because the tyre (certainly not as much as proper drag slicks) stays on the road but the wheel has already started to move. then all of a sudden (mind you this is incredibly quick) the tyre gives you a sling-shot effect start.
my best 60ft was 2.142 which is great for a fwd street car!
good n/a tip before going to the track..make sure your car works! check your oil, and all other fluids..You don't want to be dumping fluid on the track and ruining everyone's night!
Well, I thought that too, until I dynoed my car. The curve is so uneventful on an FS-DE it doesn't help any to shift at 6500. When I shift at 6000 from 1st to 2nd I fall to about 4200-4300, and that is right where it needs to be. Power drops like a rock after 5900, so why run past the power to 6500, then fall to 4700(which is past where the car starts making power?)mp5jeff said:
its so embarassing, you just want to run and hide..and/or kill yourself...thank god it hasn't happened to me yet..but i'm sure it will. (shrug)RyanJayG said:
Damn Replica, this is a great question. I just looked at my dyno sheet, and I make peak torque at about 4200 rpm. So shouldnt I shift before redline so that I will be at about 4 grand after the shift? Seems right to me, but I had always read that you need to shift at redline.Replica said:
confused,
scorch70
I really don't understand what you mean by "torque multiplying effect" through 1st gear. The car just doesn't pull after 5900, Shifting into some torque is nice and the little push the heavy fly wheel has is great. I raced another P5 last weekend, everytime I shifted (at 5,900-6,200-ish) I would pulled a fender or so. I ran the guy 3 times, all the way to the top of 4th. He even had a few more mods than me. The other P5 I raced when I first got my car lost also, because I shifted at 6k.Gen1GT said:
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
think of it this way. what power are you making at 6500rpm? and what power if you change to the next gear at 6000rpm (ie your new rpm)? i'd be certain you'd be making more power at 6500rpm than at 3500rpm when you change gears at 6000rpm...
my first run the other night my right tire got stuck in some fucksticks oil, spun like crazy and I got an oh so wonderful 3 second 60' time, I was ******* pissedRyanJayG said:
not to mention on sunday I had to wash all the tire rubber and s*** from the track off the right side of my car
Keeping it in the horsepower curve is important, because horsepower is what accelerates the car. But throughout first gear, the axles are turning 'harder' because of the torque muliplying effect of the tranny. ie if your final drive is 4.105 and your first gear is 3.8, then the torque muliplyer is 15.6. Which means if you're getting 100lb-ft of torque at the flywheel, then you're getting 1560lb-ft at the axles. Because of the extreme ratio in 1st gear, it's really the only gear that helps a whole lot with acceleration. After that, it's all about horsepower.
Look at the rev curve on this dyno chart. I know this curve is more high RPM happy than a typical FS curve, but the point is the same. If I were to shift at peak power, BEFORE the power starts to drop like you say is beneficial, it would put me at about 65whp down from 117whp. If I kept on it right til fuel cut where I'm still making 108whp, at every point above peak I'm still making more power than had I shifted, even though the power is dropping. And if I shift at 7400 it'll drop to around 4400RPM, where I'm making just over 90hp at the wheels. My point is that although hp is going down after peak, it's still more horse power than if I shift.....
Look at the rev curve on this dyno chart. I know this curve is more high RPM happy than a typical FS curve, but the point is the same. If I were to shift at peak power, BEFORE the power starts to drop like you say is beneficial, it would put me at about 65whp down from 117whp. If I kept on it right til fuel cut where I'm still making 108whp, at every point above peak I'm still making more power than had I shifted, even though the power is dropping. And if I shift at 7400 it'll drop to around 4400RPM, where I'm making just over 90hp at the wheels. My point is that although hp is going down after peak, it's still more horse power than if I shift.....
