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Laggy Gtr Need Help

elboro

By elboro,
in Engines & Forced Induction

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elboro Enthusiast

elboro

Posted
Posted

hey i was just wondering if anyone else has had this problem and might know what it is.

In the past couple of days my car has become very laggy, as in my turbo's are spooling up very slowly and not hitting full boost by redline which sucks! I dont know if i have accidently changed something on my apexi computer or maybe if it is spark plugs...? but i am sure someone on here should have a better idea than me.

Thanks, ElBoRo

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Paul B Apprentice

Paul B

Posted
Posted
hey i was just wondering if anyone else has had this problem and might know what it is.

In the past couple of days my car has become very laggy, as in my turbo's are spooling up very slowly and not hitting full boost by redline which sucks! I dont know if i have accidently changed something on my apexi computer or maybe if it is spark plugs...? but i am sure someone on here should have a better idea than me.

Thanks, ElBoRo

fuel pump myb? is it just running bad on boost or does the car seem to struggle/ hesitate through the rev range? i know when mine was on the way out it wasnt hitting boost til nearly redline and it just ran like shit...

elboro Enthusiast

elboro

Posted
  • Author
Posted

yeh you could be right... but i dont understand how the injectors could be maxing out when the fuel pump cant get enough fuel in there, i think i left that bit out. oops.

but yeh thats the story, the injectors are maxing out when its barely reaching 1 bar and its suppose to boost to 1.20 bar. The boost is really slow coming on aswell.

my_gtr32 Collaborator

my_gtr32

Posted
Posted

I don't know about that. My gtr was tunned by Racepace and runs close to 1.2 bar. Not maxing out using standard injectors and fuel pump. AFMs are getting close though. Is Ben a clown?

yes. the clowns that say you can "safly run" 1.2 bar on stock injectors need to be shot. 1 bar is around 98%
ferni Grand Master

ferni

Posted
Posted
yes. the clowns that say you can "safly run" 1.2 bar on stock injectors need to be shot. 1 bar is around 98%

what does 1.2 bar have to do with injectors? it's the amount of air, not the amount of pressure, and then it's also what AFR you run, and also if you have a FPR.. there is lots more to it. I know of a GTR that runs over 300rwkw on stock injectors, goes to the track and everything, and its still going strong, no problems?

1.2 bar is probably pushing stock turbos, but your injectors will have plenty left.

elboro Enthusiast

elboro

Posted
  • Author
Posted

yeh i dont have stock turbo's, i have got R34 N1's and i recently got my exhuast done so i have a brand new CAT.

I know with my old GTS-t i had a similar problem and it ended up been the spark plugs, but my spark plugs were changed when i got the other stuff done, so i have no idea what it is. Im taking it to my mechanic tomorrow, hopefully its nothing major.

and also i usually run it on 1.05 bar but it doesnt have much problem running 1.2 on a good night as long as i dont rev it out past 7000. The injectors are in the 90's though.

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