Does OFT raise rev limiter?

[FRSBRZGT86FAN]

Originally Posted by VeilSide

I dont think a launch control makes sense with an auto.

Usually the LC limiter is active when the car is in neutral, so if you brake and press the accelerator you will not end up in the limiter, right?

It could work if you switch the lever to N which makes absolutely no sense to me...

Launch control only really makes sense on an "auto" that can control the traction for the launch in my book, otherwise with these torque converter autos the neutral idea just puts too much wear and tear on the drivetrain. The proper way is a auto with launch control whos stall converter is adjustable electronically, something our cars wont have. Dual clutchs and the like don't have to worry about that stuff.

[steve99]

Originally Posted by renfield90

Bringing this thread back up from the dead as I'm trying to raise my rev limit, and I want to fully understand what I'm doing.

Before you tell me - yes, I know there's not much power up there. I'm doing this purely to save a shift to 3rd gear on most autocross courses which, even with a power dip, tends to be faster than up/down shifting.


So I understand this - update the fuel cut on/off values, then update the scaling in Base Timing B so the soft limiter kicks in where I want it.

The question I have is where should I scale the axis? Right now the table jumps from 7000, to 7450, to 7600, with the last one containing the soft limiter timing. I'm assuming the ECU scales the timing values linearly between 7450 to 7600? Or do the timing values used by the ECU change discretely/abruptly as the motor goes from 7599 RPM to 7600?

I'd greatly appreciate any insight anyone has. Thanks.

The ECU will "interpolate" values in between , im not sure of the exact interpolation method


http://paulbourke.net/miscellaneous/interpolation/

[steve99]

Originally Posted by renfield90

Bringing this thread back up from the dead as I'm trying to raise my rev limit, and I want to fully understand what I'm doing.

Before you tell me - yes, I know there's not much power up there. I'm doing this purely to save a shift to 3rd gear on most autocross courses which, even with a power dip, tends to be faster than up/down shifting.


So I understand this - update the fuel cut on/off values, then update the scaling in Base Timing B so the soft limiter kicks in where I want it.

The question I have is where should I scale the axis? Right now the table jumps from 7000, to 7450, to 7600, with the last one containing the soft limiter timing. I'm assuming the ECU scales the timing values linearly between 7450 to 7600? Or do the timing values used by the ECU change discretely/abruptly as the motor goes from 7599 RPM to 7600?

I'd greatly appreciate any insight anyone has. Thanks.

What your trying to achieve is the ignition retard is the initial rpm limiter buy reducing power due retarded timing, then if this fails to halt the climbing rpm the fuel cut is the failsafe.


so you just need to make the retard cut in about a 100 rpm before the fuel cut from memory

[renfield90]

Originally Posted by steve99

The ECU will "interpolate" values in between , im not sure of the exact interpolation method


http://paulbourke.net/miscellaneous/interpolation/

Originally Posted by steve99

What your trying to achieve is the ignition retard is the initial rpm limiter buy reducing power due retarded timing, then if this fails to halt the climbing rpm the fuel cut is the failsafe.


so you just need to make the retard dut in about a 100 rpm before the fuel cut from memory

Massive thanks, Steve.

Given that the two rows before the retarded timing are identical, I would guess that most interpolation methods would be roughly linear between the last "normal" row and the retarded row.

Sounds like I should just set a value, test it, and if I run into the hard limiter then I can scale back the timing a bit.