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Rb20det + Vg30 Turbo. Hestitation On Boost

rayj

By rayj,
in Engines & Forced Induction

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rayj Proficient

rayj

Posted
Posted (edited)

hi,

why would i be getting hesitation on boost? i can switch between 10 and 13 psi. there are no problems at all before the turbo starts spooling and hitting boost. but as soon as the turbo starts kicking in at around 3000rpm there is hesitation and lack of power.

i am running bcpr7es-8 ngk copper plugs. should i be running bcpr6es-8 instead with my boost? the plugs are new btw.

ive checked for leaks, nothing wrong there... i have new splitfire coilpacks. timing is at 15

could the tps be causing a problem like this?

any help would be appreciated.

thank you

Edited by rayj
rayj Proficient

rayj

Posted
  • Author
Posted
Did you mess with the plug gaps at all? As in, did you open them up or something silly?....When did it start missing? After you changed the plugs?

i didnt mess with them. all 6 are brand new gapped at .8. the car isnt misfiring at all. ther basically isnt any power on boost, u can hear the turbo spooling up, but instead of feeling the power kicking in, the car hesitates/stumbles. this only happens in the rev range when the turbo starts kicking in, otherwise it drives perfectly.

ive also noticed that if i gradually accelerate this hesitation/stumbling goes away. but if i hit the accelerator hard, then u can definately feel the problem, the car basically gets no kick from the turbo.

Rolls Grand Master

Rolls

Posted
Posted (edited)
im running a standard ecu which has been tuned

LOLLLL

What the hell did you expect?

Get an aftermarket ecu, nistune or someone with a real time tuning board to make an epprom chip up for you on a dyno. Oh and obviously pay someone to actually tune it properly, don't get a cheapskate $200 tune.

Edited by Rolls
TAKUSHI Proficient

TAKUSHI

Posted
Posted

hey mate when it does its little spit, say youre on full throttle at about 3500-4500, does it feel like the cars pulling a caravan then once it gets up to say 5500 and beyond it clears up and makes full boost?

GTScotT Grand Master

GTScotT

Posted
Posted
LOLLLL

What the hell did you expect?

Get an aftermarket ecu, nistune or someone with a real time tuning board to make an epprom chip up for you on a dyno. Oh and obviously pay someone to actually tune it properly, don't get a cheapskate $200 tune.

You do not know what he means by 'tuned', thus should not be jumping to conclusions.

The RB20 ecu has a socket for a rom chip that can be tuned (painfully) as well as any other daughterboard modified ecu.

To the OP, recheck your works and try installing the actuator from the turbo you removed and running stock boost.

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