ECU upgrade

[boarder445us]

i have a 97 240SX SE, i am going to put a turbo XS turbo kit on it , and i was wondering what ECU or chip i should get so i can hit like 150. Or is there any way to get around the cut out at 119?? LMK, thanks.

[matt0941]

Well first of all how much HP do you intend on exerting, because the stock ECU is not very reliable past 240 horse and has trouble with its MAF readings. Many people go with standalone systems like haltech or motec or piggy back systems like a'pexi SAFC or the HKS SAFR (what I will be going with). But to answer your question the JWT ECU upgrade (search for it the price is listed in another one of my posts) is very common and removes the speed govenor (sp?) as well as many other features. Anyone feel free to correct me if I am worng (not that it would stop many of you anyways )

[EZcheese15]

I agree with matt here....

In my opinion, either go full standalone, or JWT ecu. Full standalone is much more expensive, and also takes a much higher degree of knowledge to operate (you have to tune it yourself). Where as the JWT is already tuned. It's also a lot cheaper. Down side is, it's not as good. But that doesn't mean it sucks, because it's still good.

And if your goal is to hit 150mph, good luck. It will take a lot of HP to overcome the wind resistance up there, but with a turbo you should be able to do it fairly easily.

[WDRacing]

Look at Matt giving out advice like a pro...makes me proud..8)

Usually people build to reach a hp mark. since its torque and hp that will be taking you to that speed. 150 is pretty fast, you'll need alot of suspension work as well as engine work. You don't want to get loose at 150 mph.

Can I ask why your looking at 150 for a goal??

WD

[TrueSlide]

Can I ask why your looking at 150 for a goal??

Highway cruising

[boarder445us]

because i like going fast! 120 isnt fast enough. I would like to get around 250 HP at the crank... what do you guys think, ill have to get a turbo, i was thinking about getting a T4. Just wondering what ECU will work best with it.

[EZcheese15]

because i like going fast! 120 isnt fast enough. I would like to get around 250 HP at the crank... what do you guys think, ill have to get a turbo, i was thinking about getting a T4. Just wondering what ECU will work best with it.

With only 250 bhp, you are gonna have a hard time hitting 150.

That, and you are gonna kill yourself. I'm not gonna say I've never been 150 in a car, but I will say it's not smart.

[I am Technoman]

I agree with Mr cheese. Why go 150? sounds silly!unless your on the track breaking the 10's:ylsuper

[matt0941]

Just take the govenor out of your paren'ts car and devote a highway to speed breaking

[boarder445us]

ok, maybe not 150, but come on, i can do around 120 in any stock car, I want to go faster, when im at the track I have enough space to hit like 140 if there was no governor. Is there a governor you can take off or do you have to get a chip?

[EZcheese15]

ok, maybe not 150, but come on, i can do around 120 in any stock car, I want to go faster, when im at the track I have enough space to hit like 140 if there was no governor. Is there a governor you can take off or do you have to get a chip?

Um dude, what track you gonna hit 140 in on a relatively stock car?

And if you go turbo, you will probably be bypassing the governer anyway, depending on what you do for fuel management, but the point is, your goal seems awkward.

You aren't gonna hit 140 on any dragstrip, and the only roadcourses you are gonna come close to 140 on is something HUGE, like Daytona or Road Atlanta, and even that will be just a *maybe*.

[boarder445us]

dude, ok so 130! JESUS, all i am asking if if there is a governor, 120 is slow. All i wanted to know is if there is a governor that i can take off or if i have to buy a chip... so if i get this turbo my fuel management should bypass any governor in the previous ecu? is that what you are saying.

[EZcheese15]

dude, ok so 130! JESUS, all i am asking if if there is a governor, 120 is slow. All i wanted to know is if there is a governor that i can take off or if i have to buy a chip... so if i get this turbo my fuel management should bypass any governor in the previous ecu? is that what you are saying.

I'm saying 2 things:

Yes, you have to buy a new ECU, from JWT.Either that or go complete custom stand-alone fuel management.

And as for turboing your car, the only 2 methods for fuel management I would recommend are either a JWT ECU or custom fuel management, but for you, a JWT ecu (cheaper, and already tuned).

If you choose some *other* cheap type of fuel management, such as a fuel pressure riser, or SAFC, then *no*, it will not bypass your governor.

[WDRacing]

This thread scares me a little...I really want to come back to the states but...I don't want to get myself killed by some inexperiened kid who thinks he need to drive fast on public roads. Actually pisses me off...

WD

[ziggy682]

This comes straight from the FAQ on http://www.240sx.org.

"How do you remove the speed limiter?

After reading the first solution I looked into finding a simpler solution. Best of all, everything can be done at the computer. My car is a 89 with a 96 ka24de, but all the wiring and computer is 92. On my computer, there is a yellow wire with green stripe, 8th one over from right on harness. This is the vehicle speed sensor signal. Cut that wire. That is it. If you have a California car I think it will trigger a code, but for the rest of us, it is an easy trick. Your speedometer will still work because the signal comes from the transmission, goes to the gauges, THEN feeds the computer. I had to find a solution because my car comes very close to the speed limiter at the end of the 1/4. If anyone can beat the revlimiter let me know. I'm working on it."

There it is. I did this on my car, but have not taken it over 120 to verify it. Frankly, I don't see any need to ever drive over 120 unless you are on a race track. I can tell you that it did not affect anything else with my car, but I can't verify that this is the wire for the speed limiter.

[EZcheese15]

This comes straight from the FAQ on http://www.240sx.org.

"How do you remove the speed limiter?

After reading the first solution I looked into finding a simpler solution. Best of all, everything can be done at the computer. My car is a 89 with a 96 ka24de, but all the wiring and computer is 92. On my computer, there is a yellow wire with green stripe, 8th one over from right on harness. This is the vehicle speed sensor signal. Cut that wire. That is it. If you have a California car I think it will trigger a code, but for the rest of us, it is an easy trick. Your speedometer will still work because the signal comes from the transmission, goes to the gauges, THEN feeds the computer. I had to find a solution because my car comes very close to the speed limiter at the end of the 1/4. If anyone can beat the revlimiter let me know. I'm working on it."

There it is. I did this on my car, but have not taken it over 120 to verify it. Frankly, I don't see any need to ever drive over 120 unless you are on a race track. I can tell you that it did not affect anything else with my car, but I can't verify that this is the wire for the speed limiter.

I think somebody verified that that does NOT work.

The governor on Nissan's is programmed into the ECU, hard coded. You can not bypass it.

[WDRacing]

The #55 wire on Skylines makes it go by by. But thats not much help huh...lol. There should be a wire to clip on the ecu somewhere. The only reason I say that is cause the ecu has to get its speed signal from somthing. I should think removing the signal would fix the problem.

Someone, should just start cutting all the wires one by one till it goes away...lol...kidding.

Who's got a wiring diagram handy, should be right there.

WD

[EZcheese15]

The #55 wire on Skylines makes it go by by. But thats not much help huh...lol. There should be a wire to clip on the ecu somewhere. The only reason I say that is cause the ecu has to get its speed signal from somthing. I should think removing the signal would fix the problem.

Someone, should just start cutting all the wires one by one till it goes away...lol...kidding.

Who's got a wiring diagram handy, should be right there.

WD

The ECU gets it's signal from the vehicle speed sensor. Then the ECU cuts fuel and/or spark (i think both, but forget for sure) at the set speed limit. However, if you cut the input into the ECU, it will also disable the speedometer, as the speedometer gets *its* input from the ECU.

So yeah, you can get rid of it, but you will be getting rid of your speedometer at the same time.

WD, the trick you mention with the Skyline might work on OBDI cars, but OBDII is completely different.

And the original guy by the way mentioned a 97 S14, which would be OBDII. (Not sure if we are still talking about the same car, but I thought so).

[cnichols]

Who needs a speedometer?

You could always install an aftermarket one if you really wanted to get rid of the speed limiter that bad.

Of course to hit 150+ easily, you would probably have a standalone and forced induction so it wouldn't be an issue anymore.

Holy s***, just realized this is my 240th post...hey WD, can you just lock it that way? but still allow me to post? j/k

[ziggy682]

The ECU gets it's signal from the vehicle speed sensor. Then the ECU cuts fuel and/or spark (i think both, but forget for sure) at the set speed limit. However, if you cut the input into the ECU, it will also disable the speedometer, as the speedometer gets *its* input from the ECU.

So yeah, you can get rid of it, but you will be getting rid of your speedometer at the same time.

WD, the trick you mention with the Skyline might work on OBDI cars, but OBDII is completely different.

And the original guy by the way mentioned a 97 S14, which would be OBDII. (Not sure if we are still talking about the same car, but I thought so).

Not sure how this works on S14's, but it does not work this way on S13's. This wire is cut on my 1991 S13 and my speedometer works just fine. I read that the speedometer is mechanical(getting it's signal from the transmission), and then it sends its signal from the speedometer to the ecu. So if you cut the wire, your speedometer still works, but the ecu doesn't get the signal. You do have a point about OBDII since this is a 97 he's talking about. Either it wouldn't work at all, or the ECU would know something is up.