5th Gear Rev limiter into Launch Control

[Ikera]

From What I know stock 240sx have rev limiter in 5th Gear at about 5000 RPM.
(This is not a speed limiter! it only acts like a speed limiter because it is only active in 5th gear. You can stand still press the clutch put in 5th and the engine will not rev past 5000RPM)
I did research on this, and people have been trying to hack the ECU to turn this rev limiter into a lunch control activated by low speed.

That sounds too complicated @_@

What I was wondering if it's possible to wire 5th gears position sensor to clutch pedal sensor.
The car will think it's in 5th gear whenever you press the clutch pedal and will only rev up to 5000RPM. Now when you release the clutch pedal the car will not think it's in 5th gear anymore and you will have your red line limiter back. I think this is pretty much how any 2 step launch control works.

s13-5th-gear-switch-for-rev-limiter-fun ... 63282.html

[pacotaco345]

but what happens when you want to clutchkick at 6 grand?... or shift from gear-to-gear close to redline.

[Ikera]

but what happens when you want to clutchkick at 6 grand?... or shift from gear-to-gear close to redline.

Yea I was thinking about that, just didn't want to post it because first I want to figure out if it's even possible. Then test it out and then the possible find the solution for other problems.

This situation might be pretty s***. Because I think that if the RPMs are over the 5th gear limiter the ECU has a fail safe that will cut the ignition for about 5sec. 5sec is a long time, with disengaged clutch the RPMs will drop to 0

[costa_rican13]

well the stock ecu has a fuel cut. so you wouldnt want to even try to wire the sensors for the limiter. if anything get a bee R* limiter. they work i've had one before. easy to wire up and have three knobs to adjust the limiter, redline cut, and how agressive of a cut you want(like 2-3 feet flames coming out the exhaust!) and you can wire the launch cut to the e brake or the clutch whatever you like. or just get an ecu that has the cut programable. i think nistune has that option.

[Ikera]

well the stock ecu has a fuel cut. so you wouldnt want to even try to wire the sensors for the limiter. if anything get a bee R* limiter. they work i've had one before. easy to wire up and have three knobs to adjust the limiter, redline cut, and how agressive of a cut you want(like 2-3 feet flames coming out the exhaust!) and you can wire the launch cut to the e brake or the clutch whatever you like. or just get an ecu that has the cut programable. i think nistune has that option.

Oh I though the stock ECU was ignition cut limiter, I don't really know the difference but I heard the fuel cut limiter is a bad idea.

I guess that idea is out the window. End of topic

I heard a lot about Bee-R limiters, but they cost a lot money. It's not like I'm launching all the time. I thought the stock one would be a cheap solution.

And I wanted to try this one from e-bay just for fun and experience.
http://www.ebay.ca/itm/110359750284?ssP ... 1438.l2649

Doesn't seem like there is much that can go wrong. There are only few wires. should be easier than wiring an S-AFC which I've wired up with no problems

Any advice?

[pacotaco345]

I wouldn't trust something from ebay that controls something as vital as your ignition... There is actually A LOT that can go wrong with that and it could turn into a nightmare..