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Missing Under Light Acceleration?

rbracer

By rbracer,
in Engines & Forced Induction

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rbracer Rookie

rbracer

Posted
Posted

Hey,

Just had my car tuned (r32 gtst) it has the following mods:

RB25DET

Rb26 Internals

T3/T4 Turbo

50ml External Wastegate

Sard FPR

Sard 850CC Injectors

Link ECU

Now if i put my foot flat its fine and will rev out smoothly to redline but when im just cruzing at about 2000rpm it starts to miss and cough and splutter untill i put my foot down more than a quarter.

Why does it do this? and is there anything i can do to fix it?

before the injectors and link i had standard injectors and a power fc and it ran fine..

Any ideas would be great!

Thanks.

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https://www.sau.com.au/forums/topic/129656-missing-under-light-acceleration/
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ShiftyR31 Apprentice

ShiftyR31

Posted
Posted

Im no tuner so dont take my word on this but ive had the same problem in my car. What happend is that its fine when tuned at certain ranges. What happened at low range when boost was just about coming on there was a dead spot and engine would cough. This was caused due to a problem called "boost flattening" where boost wasnt holding a smooth patern in the rev range required. or something like that. Well my fix was when i dropped the rb25det into the r31 i changed computers to a wolf v400 and that fixed it.

SLIPPERY Experienced

SLIPPERY

Posted
Posted (edited)

does the link use closed loop? id say your 02 sensor would be fine since it only happened after you put the link in

cruise mixtures might need to be fattened up a bit because it seems like youre running a little lean on light throttle. Im not sure if the standard link rb25 map would be as suitable as the Power FC standard map, which may be why you noticed no problem with the Power FC.

Take the car back to the tuner and get some road tuning done with varying loads. He may have only done a WOT tune on the dyno.

Edited by SLIPPERY

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