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hello guys. any reason why an rb25det,would run 20 degrees, carnt seem to get 15 no matter what i do, unplug TB./ tryed adjusting cas. tryed turning down aac valve, somone told me autos run 20. but i put manual in it.an tryed two different ecu's but still runs on 20degrees, according to data scans. any help would be great. carnt boost over 8-9psi with out cutting out.

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https://www.sau.com.au/forums/topic/359461-running-20-degrees-timming/
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tangles- i will check,but dont think so.-

adriano- just on basic conzult or datascan.nistune, not running nistune ecu yet but. tryed on sr20 and runs 15.

DVS32R- cuts like maf limits, so basicly cuts everything, soon as i go over 8-9psi. back off a fraction and comes to life again. just a fast cut out, was thinking timing was too high makeing things max. but doesnt do it under 8psi.

now im finding car can stop randomly and start straight back up- if i shake maf somtimes(not roughly) car will just stop.. and i have to restart it... could if be faulty maf. i grounded maf to chassis few weeks back and didnt do it again, stoping random that is. not the cut on boost.

turbo is ar 60-1.00, 3'' straight threw exchaust exchaust temp sensor not in cat,its just clamped to cat,was like that when got it.but dont think thats the cause.

greeedy intake plenuim stock TB

steel headgasket

big IC

pod

fpr

38mm external

i havent check to see what fuel pumps in it ethier,will very vry soon

Edited by nisn

i had an issue like this once !

built an rb26 .... for some reason the CAS sensor LOOKED like it was set to retarded ( far left ) but timing light was telling me 20degrees ... timing was obviously retarded ( CAS ussually sits in the middle for 20degrees... plus the engine revved retarded ... checked Timing belt again ... perfect !

timing light says 20degrees ..... got it dyno'd and timed instead at chasers. still no sure what happened to that car chasers motorsport didnt know either ( they checked TB and timing light also )

apprently the bracket the holds the CAS sensor in (behind timing case) fractures in rare cases. besides that :S id like to know whats going on !

  On 01/04/2011 at 11:51 AM, TwentySix said:

i had an issue like this once !

built an rb26 .... for some reason the CAS sensor LOOKED like it was set to retarded ( far left ) but timing light was telling me 20degrees ... timing was obviously retarded ( CAS ussually sits in the middle for 20degrees... plus the engine revved retarded ... checked Timing belt again ... perfect !

timing light says 20degrees ..... got it dyno'd and timed instead at chasers. still no sure what happened to that car chasers motorsport didnt know either ( they checked TB and timing light also )

apprently the bracket the holds the CAS sensor in (behind timing case) fractures in rare cases. besides that :S id like to know whats going on !

still didnt get to the bottom of it , neither did chasers ( didnt spend to much time on it )

timing kept saying 20 ( obviously not 20 ) just played with the CAS on the dyno until we where happy :) lol funny engine

timing light loop that nissan recommends using can cause timing lights to read wrong, i had this happen the other week on a GTR, i didnt feel it was correct so i put a spark lead from the #1 coil pack to the #1 spark plug to check timing and it was 10 degrees different to the timing loop.

always best to use the spark plug trick

  On 01/04/2011 at 11:56 AM, DVS32R said:

timing light loop that nissan recommends using can cause timing lights to read wrong, i had this happen the other week on a GTR, i didnt feel it was correct so i put a spark lead from the #1 coil pack to the #1 spark plug to check timing and it was 10 degrees different to the timing loop.

always best to use the spark plug trick

+1

  On 01/04/2011 at 12:25 PM, TwentySix said:

think it may be white wire near ignitor actually ....

That white wire on the two pin plug near igniter is coil pack positive power.

The Black/Pink wire on that two pin plug is Cylinder 1 fire signal wire (On R33 GTS-t S1)

  On 01/04/2011 at 11:56 AM, DVS32R said:

timing light loop that nissan recommends using can cause timing lights to read wrong, i had this happen the other week on a GTR, i didnt feel it was correct so i put a spark lead from the #1 coil pack to the #1 spark plug to check timing and it was 10 degrees different to the timing loop.

always best to use the spark plug trick

+2 do this before anything else

ok will do that in the morning cheers, the timeing on conzult/datascan. That is reading ignition timeing right? thats what is at 20. should that be right.

in conzult,i can change timeing- the basic check.

such as check timeing cylinders,so on' i change timeing to -15.click and bam drops idle and accually sounds like where motor should run. but obusly i carnt burn to ecu. it doesnt stay at 15 when turn laptop off.

but in saying that,when i change it too -15. it reads 10 degrees on datascan??

no more when i do another timeing light read tomoz....cheers

Edited by nisn

The way it

Works is the consult timing shoukd say 15 ( or whatever te base timing is for ur engine) then u need to set the crank angle sensor timing to match the consult, u do this by using a timing light as i described above

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