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Speed Limiter


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On a '98 2.5 GT is there a speed limiter on the cars ECU system?

Does anyone know if there is a way to disable the speed limiter system, if it exists?

 

Thanks

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Guest coolb72

looking back at a test car and driver conducted in 97 on the 2.5 gt with an auto transmission it looks like the top speed is 114 mph on a two way run(drag limited) but seriously, where are u going to run that fast without losing your license and going to jail?

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Guest imjunior

114mph top speed out of a 2.5? That's it? You're kidding right. My '94 Legacy can get up to at least 118, and that was back when the engine was green. I got it up to 110 on the PA turnpike back in October going out to Fall Carlisle until my friend was like "Dude! Slow down!" There's more to the story of course. I know this has nothing to do with the original question but I would think you should get at least 120mph out of a 2.5. Of course that's just my opinion, I could be wrong.

 

(junior)

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Guest PaganQWA

Fuki: There's a pretty easy way to find out :) Get it up to 100mph, thats when they usally kick in if it has a limiter... if it doesnt cut the fuel by 120mph, it dont have one. You'll definatly know if it does :)

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Guest Legacy777

imjunior:

 

The speed limiter has nothing to do with what the engine can or can't do, it's all in the electronics, to keep cars down from those high speeds. The ECU has a speed sensor, so it knows the vehicle's speed. When it reaches that is cuts either the spark or fuel from the engine, I believe in the subaru's it's the spark, ie retards timing. There is no way to bypass this without an aftermarket piggy back chip upgrade or replacement aftermarket ECU.

 

That's just the way things go.

 

I lucked out...my 90 Legacy does not have any speed limiter or anything....She tops out around 130 mph ;)

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Guest coolb72

that mph that i put down here was tested on a two way run so that the grade and any wind will be cancelled out. so if u are going down a slight grade that will add a few mph to the cars top speed. 130 in a stock legacy is probably possible on a nice down grade but next time u run 130mph try running the oppposite direction and take the average of the two. and im sure that youll find your average of about 107mph as that is what the 90 legacy ran on a two way test run. (car and driver nov 89) peace

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Guest Legacy777

Not to say your wrong or anyone else is, but I was basically refering to top speed, and that was open road in Montana, there was varyin grades, and I had a car full of ****, believe me it's not something I'd do every day, and it took me a little while to get to that speed, when a turn came...you better be damn sure your ready.

 

As for the 107, was that a top speed run? that they did? Not to sound like I'm a nut...but when I go to my uncles from college, I almost always break 100. Anyway...don't want to start an argument about top speed, but was just curious as to if that was a top speed run in a certain distance or something else?

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Guest remarcable

That speed seems pretty slow, the 107 speed I mean.

 

I haven't had any other cars than my Outback above 100MPH and I really don't like going that fast because in an accident you have almost no chance of survival. Every 10MPH above 55 you go the chance of dying during an accident increases EXPONENTIALLY. I saw a chart when I was doing some work for the coroner, scary stuff.

 

Anyway, I know that wagons and high-profile vehicles can't go as fast as sedans or lower-profile vehicles simply because of aerodynamics. That's why those huge SUVs have V8s in them just to get above 60.

 

The 165HP 2.5L engine in my outback cannot overcome the drag on the car past 117MPH (I think that is the exact number on a straightaway).

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Guest rigfennid

i thought the Outbacks topped out at 126mph.. i'll have to check my literature, then maybe test it :P

 

i've SEEN over 110mph in my Outback, but i don't know the error factor, but 100mph+ i'm sure of

 

if you really wanna roll, get a motorcycle - nothing like 'cruising' at 130mph+.. hehehe

 

yes, my driving record is horrible - no i've never had an accident

 

to each his own

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Guest PaganQWA

My moms old New Yorker did 110 :) SHHHH dont tell her though! :evil: To bad the highway ended so quickly... passing through a stop light at 90mph is scary!

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Guest bobjr94

If a cars speed limited it many times will be based on the tires that come standard on it...if the car comes with tires rated at 113, the speed limiter will be like 115 ..if it has 130 rated tires it will be limited to like 135...Ive seen ecu's with the limiter taken out but they were like 900$

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Guest joshmould

93 legacy 140k miles 2wd only mod k+n cone. i can routeneley hit 120, and hit 125 a few times. this is either direction. ive also hit 120 in the 98 toyota sienna <thats when the limiter hits> and 120 in the rs <when my balls kick off>

 

lata

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Guest imjunior

Legacy777, I know about the limiter vs. engine thing, I was just in shock about a 2.5 topping out at 110. Didn't have a clear head.

 

coolb72, What downgrade is going to give me an extra 10mph? And how many Impalas are at the bottom waiting for me?

 

My 117/118 figure was on I-95 going through Northeast Philly on a Sunday morning, pretty flat. I let the Infinity get half a mile in front of me, he was doing about 125. I had less than 5,000 miles on the 1994 FWD Legacy L wagon and everything was stock. I've never hit any limiter action at top speed, just the few times I redlined it, then you can really feel everything shut down.

 

If I bought a 2.5 and it topped out at 110, I'd be a bit ticked.

 

(junior)

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Guest Legacy777

KEVIN....YOU LIE!!!!

 

is yours a 5spd or auto?

 

 

I don't know if anyone else has noticed this or whatever. But at least in my 90 legacy with auto tranny. Each gear goes up in incraments of 40 mph. I redline 1st at 6500 rpm it's around 40mph, second 80mph etc. SOOO TECHNICALLY I have a top speed of 160 mph. HOWEVER, I will most likely not ever see that due to the fact the auto tranny eats up the power, and the engine doesn't have enough torque to move the car that fast. Plus that takes some BIG BALLS to go that fast. I've gone 140 something in my uncle's IROC, but then it will get up to that speed faster.

 

 

Hey Kevin, gotta make sure the pics of 140 is when the car is moving that fast ;) Not just spinnin wheels in the ice or something....hehe. Technically I could peg my needle too. I've had it up to 100 though spinnin the wheels on the ice....hahahaha.

 

Ok I better stop....you guys are goin to think I'm nuts.....too late right...:lol:

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Guest rigfennid

i took my mom's old 1972 Ford Country Squire wagon (red WITH the fake wood sides - yeah, baby!!!) up to 135mph... scary, but fun - this was verified by my buddy in his '91 Mustang GT with a recalibrated speedo... it also had a 6.6 liter motor!!!

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Guest remarcable

Man, the ONE time I've hydroplaned in my subie it was with the crap XW4 tires. I was going about 65 and then all of a sudden the speedo jumped up to about 110 for a few seconds. Luckily I wasn't going around a turn or anything. Scared the piss outta me because I didn't realize I was hydroplaning right away. The AWD kicked in pretty quick and stopped me from going anywhere special (like into a tree).

 

Yesterday we got an insane amount of rain, everything was flooded in the morning and I had to drive my mom 45 minutes to the airport and back (twice - her flights got cancelled). I was loving it except for the idiot drivers. Subies are fun to drive in the rain, especially with rain tires. I was really kicking myself though, because I spent about 4 hours detailing the car Tuesday and it only stayed clean 1 day.

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Guest kevinsUBARU

LOL...that wasnt a lie:) I never said how I hit it.

 

Well, My spedo cable greese freezes every morning when it is cold. My rpms shoot up to past redline and the needle rockets to 140 and chills out for a little while untill it thaws out. :lol:

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Guest dankatz37

Guys, I am not sure you are aware of it, but most speedometers lie quite a bit as the speed increases. It is not uncommon to see a 20MPH difference when driving a true speed of 110mph. I wish I could find an article somewhere that compares different cars/manufacturers speedometers, but it is a known fact. The speed that is indicated on your speedometer is most likely more than the actual speed. You really have to compare apples to apples when you compare to what a journal like Car and Driver (who actually DOES do a top speed run unlike some other journals) gets. They sometimes mention in their articles how much the speedo deviated from the true speed.

 

It does make me wonder what the 150mph that I was driving in Germany (in a M-B 500S) really was....

 

On the issue of why Subarus have a relatively low top speed (say compared to a Passat or some other cars) I think there are a few reasons. I'll say them in order of importance in my car. First is gearing: Subaru's gearing is much longer than a car built for the autobahn. At our top speed we are not even close to the redline (something like 1800rpm less). My BMW is much lower geared than the subaru. Even my lowly 1.8liter 318is is ELECTRONICALLY limited to 130mph. Ideally you want to be much closer to the redline because what really matters is where your max HP is achieved, not torque (for top speed, not for acceleration). Second: drag coefficient. My 96 Wagon's drag coeffiecient is .35 (AFAIK) which is relatively bulky these days. This is partly due to the fact that the car seats high off the ground and is tall.

 

I am sure there are more reasons, but realitly is that what is sold to us in the US is not meant to go very fast. I personally find my car cruises well at 90mph, but higher than that I feel that our roads and drivers are not suited for.

 

Dani

96 Legacy 5speed with a car and driver measured top speed of 107mph (drag limited)

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About the frozen speedon cable: could'nt happen to me cause the tach AND speedo are electronicaly driven on the 96 Legacy. There was still a mechanical speedo cable on the 95 Imprezza??

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Guest Legacy777

dankatz37: I'm not goin to argue about the top speed thing. I have however been to 120+ mph speeds in other cars too, being corvette, and Iroc, and get around the same feeling of speed on the same road with different vehicles. I don't think all three car's speedo's are off by that much, especially the digital speedo on the corvette. Also a friend and I have paced each other around 120. I'm not saying what car & driver did was wrong. But don't necessarily take everything you read as something in stone.

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Guest mile hi sub

All subies are supposed to be limited in speed I have heard 104mph approx?? Any way if you conntact JC Sports.inc in Denver they have a little item that eliminates the top speed limiter and it also gives you a few more HP to get there. It is called a Torque chip and really works pretty good at a reasonable price.

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