115mph Cut-off

[240TweakerNewbee]

Maybe I’m wrong for wanting to do this but, is there any way to remove the 115mph governor on my 89' 240sx s13. It really fried me the other day when I was killing a Neon till I hit the 115 cut off . I looked over the wiring diagram in the manual, and it kinda leaves you hanging as to where it is. If anyone can help me out with this I would greatly appriciate it.

[Florida240sx]

Yea it's pretty simple.Only problem I have had is that I have to shift to 5th at 100mph otherwise I lose all power. What year car you have? I have a 93 if you look at your ecu it's the 8th wire down from the top yellow with green stripe.I'm ordering a digi camera tomorrow night So if you can wait till this weekend I will upload some pics for ya.Maybe I can find the links that I used to get this info and give them to you if you want to do it now.

[240TweakerNewbee]

Yeah, the car is an 89, thanks for the reply. Good to know there is hope with this, I was looking at a product from HKS called a "speed limit defencer" but costs $125.

http://www.hksusa.com/categories/?id=1926

I just don't think its worth all that when it comes down to wiring, even if I get a check engine light for disconnecting it, I can always make a toggle switch for it or just reconnect the wire when I need to smog.

Oh and before I forget what is this butterfly valve thing I have heard mentioned in some of these forums with the air intake that is supposed to also be some limiting factor in which its removal will help increase power?Im curious to know these little tidbits of information that can help the old beast keep up with the new stuff.

[sanioll]

you dont need to cut off speed limiter on your cheap *** 240 and you're not supposed to street race. Especially with dodge neons. Shame on you!!

your suspension is not adequate to run above 100mph and your tires are probably H rated or below.

After upgrading your suspension, brakes, tires, then you may think about taking your vehicle to track to test its top speed.

Drive like a human being on the road, mmmmkayy?

[j-z]

i would like to know how to disable this on my 95 as well. a picture would be great.

[NismoGreg]

I cut my speed sensor wire on my '93 and it worked(no check engine light) but you still have to worry about your rev limiter because it 4th gear tops out at 6400 rpms and 5th gear tops out at 5000 rpms. With the speed sensor wire cut, my car tops out at around 120-125 mph.(its hard to tell when the speedo only goes to 110). Here is a link that tells you which wire to cut. After clicking link, scroll down to rev limiter/speed governer

http://www.240sx.org/faq/index.html

[Florida240sx]

I hit 126mph 2nights ago.I think that's right.We had discussion on here somewhere of RPM x (.xxx)=Speed I was going 5600 in 5th

[Florida240sx]

Anyone remember that ratio? it was like .022xxx What's our speed at 3000rpm in 5th?

[FliMSiCaL]

3k rpms in 5th is righ about 68 mph 3500 rpms in 5th is exactly 80 mph. My speedo doesn't work all that well, so i've had to rely on the tach for speed for quite some time. mine cuts at 115, and i'm running 4900 rpm in 5th. BTW, H rated tires are 130mph, its the s rated that'll kill ya

[wild_maxx]

is it true if you swap out your manuel ecu for an automatic ecu that i will not limit your top speed or fuel cut?

[Kouks]

yes its true, switch to an auto ecu and you will no longer have a speed or rev cut!

[Florida240sx]

80mph/3500rpm=.022857mph/rpm.022857mph x 5600rpm=127.9992mphThats how fast I was going.

[240TweakerNewbee]

My tires are V rated, the suspension is new and drives better than most new cars that I have driven recently, and Ive seen Neons that can do high 11's - low 12's in the 1/4 mile. Assuming you know any math you can figure out that the Neon's would have to be going faster than 100mph in order to achive the distance of 1/4 mile in that short of a time period . So to say that I was racing one and winning would indicate that my car not only has the ability to go faster than the rev-limiter would allow but it can get there very quickly and smoothly.

to all BUT sanioll; Thanks for the help

[DriftNasty240]

AEM makes a chip that will disable your 115mph governor, but you have to fork out $120 or so for it. I think it's worth it, but that's up to you :-)

[Kouks]

Hey driftnasty, i noticed you live in J-ville, you on 240sx.net? If not, you should ckeck it out. the chip takes off the rev limiter also?

[Atomic-S14]

isn't any car that can do 11's - low 12's faster than a stock 240?mines slow in stock form. even a freaking 92 honda civic with a vtec pulled on me on highway -_-;;;

[Florida240sx]

No stock 240's run 10's........You got beat by a honda...the disgrace of that...some people say they have run 15.5 with stock 240 most people run right at 16seconds while a civic best speed in the 1/4 is 16.9 or was it 16.7 but that's with professional drivers(after they tested, these cars are worthless because there was no redline factor for them)

[Kouks]

I run 10.2's @ 68.52mph stock in the eighth mile. NO LSD SOHC! the tire were worn out BFG regular tires.

[n_bogie]

save your money. 100 to 1 you never will run 115 mph in the 1/4 mile and secondly on main roads 90 mph and faster is automatic behind bars so people think wisely about goin this fast the cut off is there for a reason

[Florida240sx]

I run 10.2's @ 68.52mph stock in the eighth mile. NO LSD SOHC! the tire were worn out BFG regular tires.

Are you being a smart*ss?Or are you just plain stupid.Or did you misread my post.

[midnightclubbaa]

My tires are V rated, the suspension is new and drives better than most new cars that I have driven recently, and Ive seen Neons that can do high 11's - low 12's in the 1/4 mile. Assuming you know any math you can figure out that the Neon's would have to be going faster than 100mph in order to achive the distance of 1/4 mile in that short of a time period . So to say that I was racing one and winning would indicate that my car not only has the ability to go faster than the rev-limiter would allow but it can get there very quickly and smoothly.

to all BUT sanioll; Thanks for the help

???????

by neons do you mean Srt-4's and the more i read that the more confused i get

[Drift Machine]

I hit 126mph 2nights ago.I think that's right.We had discussion on here somewhere of RPM x (.xxx)=Speed I was going 5600 in 5th

Yep, the fastest you can go in a stock ECU 240sx is 126mph.

[DriftNasty240]

Kouks- checked out 240sx.net- preciate it- yeah, the chip from AEM kills the rev limiter, but other than that, I dunno too much about it. Holla on AIM if you wanna go drifting, same as my username.

[TogueDrifter]

on a stock twin cam from an s13, if you where able to go past redline with no rev limiter.... what would give on the engine first if you kept going? Valve Train??

[Kouks]

I was being a smart ***, you meant 1/4 I now, trying to be funny, but guess it didnt work, oh well. maybe next time right...????

[PsyckoDrifter]

isn't any car that can do 11's - low 12's faster than a stock 240?mines slow in stock form. even a freaking 92 honda civic with a vtec pulled on me on highway -_-;;;

Thats sad...is urs a single cam??...i have a 93 SE and i took a 94 civic w/vtec wit three ppl in my car and my subs in the back...i also took a 99 SI NO PROBLEM...you should rape their lives with the 240...you have a better launch and more torque...but why bother drag racing...take em to the canyons...then watch them slowly but surely fall behind...if ur a good enough driver...you should see no sign of them in about 5 turns...

[Florida240sx]

I was being a smart ***, you meant 1/4 I now, trying to be funny, but guess it didnt work, oh well. maybe next time right...????

10-4 just checking.I'm sick right not so I'm taking everything the wrong way and attacking back so please forgive.

[ralphdig]

Just modify The hex value at adreess H0031 in your Ecu eprom and you are done!

[Chezedik]

manual still limits. What you have to do is find the yellow wire with the green stripe on the ecu harness, cut it. THat's it. I found without real suspension mods or aerodynamic mods, I was limited to what I estimated to be 137MPH. So, for the most part, unless you NEED to go 135 in your base a$$ street car, leave it alone, and you never have to worry about getting busted on an inspection. Or flipping your car like a Vette at 160.

[ralphdig]

The byte at H0031 is the value of your speed limiter but you can change also the RPM limiter.