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Hi,

I'm having problems with my rev limit. I was driving my car hit limitter and i got the normal bang bang bang, and holding at 7300rpm, i then happen to hit the rev limit, again and then i got a very odd sounding bruuuu bruuuu (or baaaaaaaa) and the limit doesn't hold at 7300rpm it just keeps increasing but very slowly,

I went into the pfc h/c to see if my rev limit had been increased but it was still 7300rpm, i try to dropping it to 7000rpm to see if it made a difference but i still get the same result.

The best way i can describe what it is doing, is on a bee-r rev limitter you can set the gain of how fast/slow the limitter acts, its like something has set the limiter to a very low gain and it can't stop the engine from increasing the rev :(

I'm very worry because i was just driving the car and then all the sudden it just change :D the car still drives fine boost fine etc etc

my car is r33 rb25det, mods hks turbo, injectors, fuel pump etc etc 251rwkw

thanks michael

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whats the actual problem? the rev limit isnt a hardset cut, its a soft cut so its possible to bounce past it a little, ie if the rev limit is 7300rpm you can goto 7301rpm for example, probably up past 7600rpm if you bounce off it hard enough

whats the actual problem? the rev limit isnt a hardset cut, its a soft cut so its possible to bounce past it a little, ie if the rev limit is 7300rpm you can goto 7301rpm for example, probably up past 7600rpm if you bounce off it hard enough

the sound and characteristic of the limiter have changed, the limiter now sound something like you would get in a holden, which before it was like a machine gun bang bang bang,

and its not like its bouncing off the limiter, its like it hit the limit then the rpm slows down and increases slowly,

edit, i will go drop the limiter down to 4000rpm and take a vid as that may better explain the problem

the bang bang bang sounds as though it was retarding the timing, or cutting the spark, and the bang was the fuel igniting in the exhaust. what you have now is probably removing the fuel, which is better for your turbo. the sound you have now is what the limiter on the stock ecu sounds like.

the bang bang bang sounds as though it was retarding the timing, or cutting the spark, and the bang was the fuel igniting in the exhaust. what you have now is probably removing the fuel, which is better for your turbo. the sound you have now is what the limiter on the stock ecu sounds like.

nope its not that,

this limiter doesnt sound anything like what the stock ecu limiter sounded like.

like i mention i was driving the car, hit limiter sounded normal (bang bang bang), then about 1-2min later i hit limiter again and it sounded completely different and the rpm keep gaining not bouncing like it normal does

ok

went and try the limiter just then, it looks like its now bouncing like it normal does but still something doesn't sound right :D

at 3500rpm it sounds all sick :wub: but at 7300rpm its starting to sound normal, but still something doesn't sound right

here are the links to the vids

th_Video000.jpg

th_Video001.jpg

now i listen to the vids again, the 7300rpm sounds about right, maybe something random happen yesterday when i was driving to course the odd sounding limitter and now it has fix itself :/

sounds like ignition cut rather than a fuel cut.

factory = fuel cut

most other aftermarket computers = ignition cut (because its safer)

ill put up a vid of what my car sounds like with the ignition cut @ 3500 and 7000 for you to compare if you like.

sounds like ignition cut rather than a fuel cut.

factory = fuel cut

most other aftermarket computers = ignition cut (because its safer)

ill put up a vid of what my car sounds like with the ignition cut @ 3500 and 7000 for you to compare if you like.

that would be great :D

thanks

  • 6 years later...

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