R33 Flat Lines Once It Hits Limiter?

[mr-r33]

Shhhh......

Not too sure on the various relative pressures on the intake side when cutout occurs but it sounds like you are revving it too hard anyway.

Sounds suspiciously to me that the problem might be due to an after market BOV that is causing the engine to give the sensation of "dying" when it hit cut-out. This cutout should not make the car die completely until the next gear. I came to this BOV conclusion since you said it also pops on overrun - so do you have an after market blow-off valve? If so put a stock one on - it will make the car much nicer to drive in many subtle ways - trust me/us.

As for the shift point question - it's all about maximizing the amount of work or energy put into moving the car from the engine. This energy is proportional to the area under the POWER curve and is influenced by the RATE of increase of torque before the powerband compared to the RATE of decrease after the powerband. The best shift point (for racing) is determined by shifting at a point where the revs for the next gear will fall to a rev that maximizes the area under the power curve before the next shift point. This is slightly different for each gear as the rev range is compressed as you move up the gears - at least on a road car.

For street use I would say shifting around 5500rpm is a nice balance - I would use 6200rpm on a track and maybe 6800 if you want to overtake someone. Avoid rev limiter - unless driving a V-TEC or 4AGE - they love it

nope i have a stock BOV

the mods the car has is 3.5" turbo back exhaust, A/market low mont manifold, stock turbo on 10psi, GTR fuel pump and a HKS pod filtter

[Birds]

Shhhh......

Not too sure on the various relative pressures on the intake side when cutout occurs but it sounds like you are revving it too hard anyway.

Sounds suspiciously to me that the problem might be due to an after market BOV that is causing the engine to give the sensation of "dying" when it hit cut-out. This cutout should not make the car die completely until the next gear. I came to this BOV conclusion since you said it also pops on overrun - so do you have an after market blow-off valve? If so put a stock one on - it will make the car much nicer to drive in many subtle ways - trust me/us.

As for the shift point question - it's all about maximizing the amount of work or energy put into moving the car from the engine. This energy is proportional to the area under the POWER curve and is influenced by the RATE of increase of torque before the powerband compared to the RATE of decrease after the powerband. The best shift point (for racing) is determined by shifting at a point where the revs for the next gear will fall to a rev that maximizes the area under the power curve before the next shift point. This is slightly different for each gear as the rev range is compressed as you move up the gears - at least on a road car.

For street use I would say shifting around 5500rpm is a nice balance - I would use 6200rpm on a track and maybe 6800 if you want to overtake someone. Avoid rev limiter - unless driving a V-TEC or 4AGE - they love it

Man, all you've done here is re-iterate what me and mad082 have been discussing, just presented in a more confusing way...unnecessarily bringing energy into it too.

[simpletool]

So it's not your BOV......hmmm. OK, I don't have a better idea. Except to change at 6500rpm or below.

Birds: OMG haha...unnecessarily bringing energy into? Maximising energy is the point - how are you meant to maximize energy without even mentioning it? It IS about maximizing the energy which is area under the power curve - it is not really related to the rev where maximum torque is produced. Yes, a lot of what you guys said was not false but also not exactly a good answer.

Edited July 23, 2009 by simpletool

[simpletool]

Birds: After reading your posts I admit I was wrong when I wrote that a lot of what you guys said was not false. Almost EVERYTHING you have typed is false if you want to maximise energy and acceleration. It is area under the power curve not torque curve - this can be a BIG difference between engines. Clearly what I wrote is above your level of comprehension if you think what you were typing agrees with what I wrote initially.

Mad082 is much more on the ball.

Edited July 23, 2009 by simpletool

[Birds]

We are talking about rotating moving parts...there is no need to mention energy when both torque and power suffice as terms of explanation of engine nature. Not only this, but your post was incredibly confusing, not well written at all, and does nothing as far as explaining the concepts you are trying to get across to people. Atleast mad082 explains his points. We are also talking about acceleration here, not power. Force, not energy. Torque is therefore the focal point on the topic matter. You sound like you need some physics lessons mate...because from what I see you have absolutely no idea what you are talking about.