Possible 2 step for stick shift cars...

[IntegraVTEC]

I've got it working fine on my '00 Z-28 M6... I left the P/N limiter set at stock and used the rpm vs gear table and set the P/N on the table to 5,000 RPM. I'm not using this to launch though. I use this feature more or less as a full throttle shift as it cuts fuel when I push the clutch in when I'm above 5,000 RPM. So when I shift at 6,000RPM the fuel cuts until I release the clutch becuase surely it doesnt take somebody that long to shift. I still have a stock clutch and it helps me out on clutch slipping issues by limiting the fuel to the engine until my clutch is fully engaged. I have used this as a launch control also but it sucks to drive around town with because as soon as your foot touches the clutch pedal the P/N limit will activate. But as long as I'm racing it works great you just have to make sure you are completely off the clutch pedal or it will set the limit back down to your set P/N limit.

[RWTD]

Not sure if this has been mentioned here yet or not, but on a '99 to '04 Ford Mustang one can set a fuel based two-step. With the clutch neutral switch activated, the pcm will allow for a neutral based rev limiter, but will switch over to the drive rev limiter once the vehicle speed sensor states the vehicle is over 0.5 mph (or whatever you set it to), so it will not come into play when moving. When the clutch neutral switch is not active, the neutral rev limiter works as normal. If for some reason it doesn't work then the clutch switch is faulty or not actuating correctly. Now for all this to work, you do have to modify a couple of parameters (switches) in the pcm.

This trick can also work on the '05+ Mustangs, but unfortunately it causes issues with the ETC system.

Regards,

James

[sultan]

any one tried this on a 2002 corvette Z06 ?

[NigelTufnel]

FWIW, I have this working on my 2K C5 with manual trans. I have the cutoff set at 3800 and resume at 3799. While it does build boost at the line, there is a delay or lag between cutoff and resume (probably because the engine overshoots the cutoff limit of 3800 RPM). For example, the engine will rev to 3800 RPM, then for about a quarter second the engine seems like it is being shut down (obviously, since fuel is cut off) and then it hits hard again until 3800 RPM. This cycle repeats and does cause some front end shaking.

The above occurs because even though the cut off is set at 3800 RPM, the engine overshoots this limit by a certain amount (e.g., lets say 50 RPM). Fueling is not resumed until the engine coasts down from 3850 RPM (or whatever the overshoot is) to below 3799.

Also, my STS kit came with a bracket for remounting the clutch switch so it is less sensitive. I do not have any issues with the cutoff kicking in too early or being overly sensitive when I press the clutch pedal, so I guess the bracket does its job.

[Fran D]

Trying to get this to work on my 01 SS M6(T-56) without any luck. Mine works like I want with the clutch in(4000), but also kicks in in 1st and 2nd@4000 also. 3rd and 4th work normally (6400).
It seems like it should work, but I tried it several ways between the RPM vs. Gear table, and the P/N cutoff.
Can this be done?

This is the exact same thing that's happening on my 00 SS M6. What, exactly, are the set up parameters for those of you who have gotten it to work with an 00-01 LS1 M6?

[Wilde Racing]

Now the next question, how to get this to work on a A4 trans.....

[WS6FirebirdTA00]

You would have to have the switch on the brake, not as easy...

[BADSZ28]

FWIW, I have this working on my 2K C5 with manual trans. I have the cutoff set at 3800 and resume at 3799. While it does build boost at the line, there is a delay or lag between cutoff and resume (probably because the engine overshoots the cutoff limit of 3800 RPM). For example, the engine will rev to 3800 RPM, then for about a quarter second the engine seems like it is being shut down (obviously, since fuel is cut off) and then it hits hard again until 3800 RPM. This cycle repeats and does cause some front end shaking.

The above occurs because even though the cut off is set at 3800 RPM, the engine overshoots this limit by a certain amount (e.g., lets say 50 RPM). Fueling is not resumed until the engine coasts down from 3850 RPM (or whatever the overshoot is) to below 3799.

Also, my STS kit came with a bracket for remounting the clutch switch so it is less sensitive. I do not have any issues with the cutoff kicking in too early or being overly sensitive when I press the clutch pedal, so I guess the bracket does its job.

What tables did you set the 3800 to?

Anyone else have success with this?

[Wilde Racing]

You would have to have the switch on the brake, not as easy...

I was thinking of some way to have the PCM "think" it is in p/n, but still have the trans in gear. Stage, hit the switch and drop the brake and run 10's......



Well after doing a few tests in park. I was able to build up to three pounds of boost at 3000 rpm. When I pulled timming down to 0 I could build a pound or two more. But now the engine has a tick (sounds like piston slap) so I'm done playing around for now.

[ZTwentyAteU]

just for the record...I used this tonight at the track at 3000/3000 on the P/N table. It works great but sometimes seems like it reactivates on the 1-2 shift

[BADSZ28]

Can anyone confirm that the clutch pedal switch is the P/N switch?

[IntegraVTEC]

Can anyone confirm that the clutch pedal switch is the P/N switch?

in my 00 Z-28 M6 pushing the clutch pedal in will activate the P/N limit. And it doesnt matter if you are sitting still or going 120mph when my clutch pedal is pushed in the P/N RPM limit is used!!!

[Full-Force]

I tried it on my 99Z and I set it to 4000 and it would not let the car go over 4000 in 1st and maybe 2nd gear. Third gear and up were fine

[WS6FirebirdTA00]

if your gear ratio goes over a certain limit, it will not work

[BADSZ28]

if your gear ratio goes over a certain limit, it will not work

I don't understand this comment. Can you explain?

[WS6FirebirdTA00]

If your gear/tire combination exceeds some sort of limit within the computer, it will not allow it to determine which gear the car is in from what I understand.

[repo]

Could this be used on a transbrake with a external push button to send p/n signal to the computer? Just trying to save 200 bucks on a msd 2step.

[Juiced91Z]

Just buy the 2 step, its 1 wire to a button or hooked up to the clutch switch (how mine is set up)

[Bayer-Z28]

We will take a look into this to make sure.

The way to go is to cut the fuel, not the spark.
Raw unburned air/fuel going out the exhaust will turn
the Cat into a blowtorch.


Ken

Or wash the cyls down.. Either way it's not good.