4age BT speed cut??

[Q Ho Lee]

I drive a BT 5 speed manual with a BT auto ecu.

My speedo shows way over 180 kmh but due to my final drive being 4.7. . Its not going that fast

So it looks like every time I hit 200++ on my speedo( not sure cus the speedo only goes till 180) I get a fuel cut. . The rev just dies and the throttle doesn't work until my speed come down and it moves again. So I'm guessing the speed cut comes in rnd 180 and my guess is that the Japanese ecu has a speed cut at 180 but from what I hear 4age ecus don't have speed cut. .

Also when I'm running low on fuel. . I get the exact same speed cut but at lower speeds 140~160
Could my fuel pump be faulty?

 

[me2kimi]

Hi Q Ho Lee, I'm driving MT 5 speed SVT with AT BTop ecu.
This is what I got when reach speed cut using GPS speedometer.

 

[lkeong88]

Dont understand what does your final drive have to do with all you are saying.

All JDM car got speedcut at 180 even evos and imprezza

 

[KHWONG]

My speedo shows way over 180 kmh but due to my final drive being 4.7. . Its not going that fast

What do u means on this? Changed of final to 4.7, means ur engine need to rev higher to achieve 180km/h.. It shud be on 5th gear on c56 need about 7k rpm to get this speed I guess... This need paging for some gb expert to come here to do some calculation ..


Can u tell us what gear with what speed u getting?

 

[Jakk]

all jdm car having speedcut @ 180kmh. (not sure about GTR )

unless u remove it by installing pivot speed meter or RSM.

 

[Q Ho Lee]

Thanks guys for your replies. When you change your final drive. . It requires the engine and gears to rotate faster to achieve the same speed as you would with a lower ( stock) ratio, this then is not accounted for and ur speedo shows a faster reading then what ur actually going. Sorry if I confused you.

My point was I have a speed cut and I wanted to know of it was a ecu, mechanical problem or if it was a speed cut cutting in.

 

[Jakk]

Thanks guys for your replies. When you change your final drive. . It requires the engine and gears to rotate faster to achieve the same speed as you would with a lower ( stock) ratio, this then is not accounted for and ur speedo shows a faster reading then what ur actually going. Sorry if I confused you.

My point was I have a speed cut and I wanted to know of it was a ecu, mechanical problem or if it was a speed cut cutting in.

sounds like a speed cut.

 

[meg_omen]

ecu...
put in RSM or Pivot Speed Meter...

 

[20V Trumpeteer]

my experience last night..
Was installing the OCT in the afternoon...then by night,I took the highway to my house...after the toll booth, I tried to put pedal to the metal and my speedo shows
beyond 180kmh w/o any fuel cut or speedcut feeling i.e lost of power or something...I also cant believed my eyes ...I thought maybe this speedo 'stuffed' with 'angin' only, that's y it becomes lighter...but the feeling of reaching speed beyond 180 is like my balls are already on my forehead la...:help:

 

[me2kimi]

How much is over 180 kmh bro? From my experience, using SVT engine both using SVT ecu and BT ecu got speed cut at -+ 190kmh.

 

[20V Trumpeteer]

village people says 'habeh meta'...hahaha....the speedo dial is down lower than 180 mark...dont dare to step more....before this, it's really hard to reach 180 mark,the highest is 170++ and it cuts

 

[judean]

well...
hv to ask my wife then...
cuz normally she drives my car faster than me...

 

[Q Ho Lee]

bro kimi. . my speedo needle points to about almost 6 o'clock position i think? and do you want to meet up for TT? because im thinking of overhauling myself... but id like to get some advice from you hehe im around pj area btw

 

[pcmoddingmy]

All 20v with stock unmodded ECU will have speed cut around 180-190kmh and note that the speedometer accuracy heavily depends on the wheel size and chassis. Best is to use GPS tool on your smartphone to get the actual reading which is usually lower than what you see on your speedometer.

When the speed cut kicks in, you will feel that the fuel has been cut off from the engine and forcing the car to slow down to around 170-180kmh until the fuel is supplied again.

 

[Q Ho Lee]

Thank you pc modding, sounds like it. . So off to find a rsm hehe, will there be a similar fuel cut when I drive it hard with almost no petrol? Happen to me a few times. . But I could still drive it for a few more minutes till I got to a petrol pump, hehe thank god