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i have done a quick search for how to get rid of the speed limiter as i hit it 4 times on the way home from work today(isolated country road) at 185klms an hr at 4500 rpm ish. i would like to get rid of this and actually see what the thing can do.

are you able to bridge this out or isloate it in some way so i can wind it out and pass my mates modified ss crumpledorre above these speeds?.

before the hounding starts i am an ex-racer of bikes and karts and i know the road etc. and you can see for miles if there is anything/one coming the other direction.

a group of us use the road for testing of race cars/bikes all the time and the best part about it is that either end of the strip there is about 20k's of tight mountain roads that get the tyres nice and sticky too.

Yeh, I was cruising on the speed limiter for about half an our the other day.

Its really annoying, because i know i could have made even better time :thumbsup:

Id be interested to know how to do this too. I know there is a speed cut defender, but it must be a lot more simple than that.

Went to a dyno shootout last weekend and both skylines maxed out at 150/153 HP. I believe it may have been the speed limiter kicking in.

You could hear them making good power, then at little over half revs they would develop what sounded like a missfire.

Q. I've only been upto 170 so I dont know exactly what it feels like - is it a missfire or does it electronically overide the accelerator like it does in a coach/truck?

(170...b/c it was only an SS dunnydoor, so not much of a race, plus we were on our way to church)

Anyhow, if anybody knows which wire to snip to disable the limiter then I would be glad to hear about it.

It feels... like a speed limiter...lol

Its not like a rev limiter, think of when you are playing Gran Turismo and your car is maxing out at like 400km/h and its like, a slow increase in revs, then a drop, then a rise, then a drop. Quite a slow process.

Its not very harsh either.

how yaz doin? i have the same problem i've found the solution well if your running an rb20det have not tried it yet as been busy but hofully will have it done by this week end...

Remove the speed limiter: Cut wire #53 on the ECU harness to disable the 180 kph speed cut. The wire is yellow/green with a silver trace. Insulate the bare ends with tape. There has been talk that this effects the hicass, but from what i've seen posted around the net driveability of the car is not changed,

Re: Speed Limit Defence Cut.

If you cut wire 53 all it does it prevent you from exiting the HICAS DIAGNOSTIC mode… Its therefore better to place this speed cut on a switch so you can still exit easily.

thanks to www.rb20det.com for this great piece of advice.

I've hit the limiter a few times as well,it's a pain in the arse.

I wouldn't advise just cutting pinouts on the ecu. besides just putting fault codes into it,you may lose the dash's speedo display,or even gears,as the gearbox ecu may no longer receive speed informaton...

it is much safer,although more expensive to fit something to rectify the problem. either a power fc to do everything,or an interceptor to cancel the speed cut like an apexi RSM,HKS SCD,or a pivot SML-M.

I have the pivot speedo/timer/speed cut eliminator on hand,and will fit it when I get time. will let you know results if you like.

Edited by fergo308

I would also not advise cutting the wire, or doing anything with the speed limiter. if you're ever in an accident and the car is inspected by the police and they find the speed limit wire cut they'll void your warranty and rego. i wouldn't want that to happen to anyone here

how yaz doin? i have the same problem i've found the solution well if your running an rb20det have not tried it yet as been busy but hofully will have it done by this week end...

Remove the speed limiter: Cut wire #53 on the ECU harness to disable the 180 kph speed cut. The wire is yellow/green with a silver trace. Insulate the bare ends with tape. There has been talk that this effects the hicass, but from what i've seen posted around the net driveability of the car is not changed,

Re: Speed Limit Defence Cut.

If you cut wire 53 all it does it prevent you from exiting the HICAS DIAGNOSTIC mode… Its therefore better to place this speed cut on a switch so you can still exit easily.

thanks to www.rb20det.com for this great piece of advice.

You can 't do that on an auto the ECU doesn't know the speed to change gear.

Speed Cut Defeater/Defender/Defencer ($150 from Nengun)

http://www.nengun.com/catalogue/product/759

What they do is allow normal (accurate) speed readings to get to the ECU up to 170 kph, so the gear changes etc are as per normal. Over 170 kph they limit the outgoing signal to the ECU to 170 kph, so the ECU never sees 180 kph and hence no speed limiter action. This doesn't effect gear changes as we should be well and truly in top gear at 170 kph.

:) cheers :)

Edited by Sydneykid

wow im amazed the last time i posted something like that on a forum i may as well got told that i am very naughty and that i should go to my room! hhaahah good to see that i am not the only one to want to get rid of the pesky limiter.

as it was i got to around 4500rpm in top (5sp manual) when it kicked in at a little past the 180 mark, so would be interested to find the end of its rope so to speak.

this is with a stock engine/driveline in a series2 only mods so far are koni suspenders,lowered springs and gtr rims.

i would like to see what it will do before i put a boost control and cooler on it.

if anyone on here has done so in a series2 man. i would like to hear so i know what to expect when its modified further.

Don't count on the speedo being accurate, mine was reading 170 kph at a genuine 164 kph with almost brand new 225/50/16 tyres. As they wear it would become even more optimistic. With the larger diameter of the 245/40/17's it's a bit more accurate.

:P cheers :(

Edited by Sydneykid

PowerFC = no speed limiter, still the fastest I've had her is only about 130-140kph, obviously on private roads, as I dont see the point in taking a road car beyond that, I dont have a deathwish, not stating you guys do, but most QLD roads just arent built to allow a car to travel at those speeds safely, they are just not smooth enough in my opinion to safely travell at 150kph+ speeds for lengthy amount of times, well my opinion!

I think you're exactly right. unless you want to drag/race the car (which stageas aren't built for) then you don't need to remove the limiter. i hit 160 along my parents private road whenever i go home to Bathurst, but other than that i don't ever get much above 120 (maybe 130 on the hume)

No I think Rockhampton has the crappiest roads in Australia! :( But yeah the only decent road I would trust to go over the 140kph for lengthy periods of time would be the new section of the M1, from Beenleigh to Nerang, other than that the national highway is a joke compared to other contries I've driven in. Mainly because Australia's population is so sparse I beleieve there just isnt the funding to keep them in the condition they should be. Although Canada relatively has the same population, maybe a couple of million more, and they have some great road infrastructure.

Anyway I have tottally gone off topic and am ranting like an old man.... back in my day............ :) Back on topic now.

  • 2 weeks later...

Pivot speed Meters go for between $90 and $150 online. Check out ebay or modyourcar.com

These will both remove speed limiter (safely, without HICAS issues) and read up to 350km/hr.

Also gives fairly accurate 0-100,200,300 and 400 metre times

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