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Rb25Det Flat Spot In R31

ianga

By ianga,
in Engines & Forced Induction

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ianga Apprentice

ianga

Posted
Posted

Hello Guy i have a rb25det in my r31 and i have a flat spot between 4000 - 5500 rpm then it picks right back up again. now i have done a search but couldnt find what i wanted

car is running 11psi

plugs have been changed and regapped to suit more boost.

has a little miss at idle and sits around 500-600 but once around 1000rpm its fine.

stock ecu

checked timing

i am going to rev zone and putting it on a dyno in a few weeks not much they can do with a stock ecu tho.

any help on this problem would be great

Cheers Adam

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https://www.sau.com.au/forums/topic/375733-rb25det-flat-spot-in-r31/
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GTScotT Grand Master

GTScotT

Posted
Posted

The boost is the first thing to check, put that back to 8 or 9 as stated.

The other thing is to make sure ur VCT is working.. A search will bring up a few threads about testing VCT.

Room42 Proficient

Room42

Posted
Posted

The problem is the stock ecu. Get a power fc or better still a mafless ecu and put it in. Dont worry about taking it to the dyno yet, its a waste of money. Put that cash toward your new computer. It will feel like a new car once the computer is in and tuned. Your car will have about 150rwkw give or take.

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