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Ok,

auto r32 gtst

pretty stock

1.Now when i boost, there is a loud spooling noise. Starting to think its a manifold leak.. would it be intake or exhaust ?

cause the standard boost gauge reads +5-+7 .. this noise comes on with or without boost controller. (after searching, it maybe a manifold leak. Can i test this myself? im farily mechanicly minded too, but dont want to pull the whole stupid thing apart.) ---

also...

2.I seem to have a major lag problem.. No matter what gear(auto remember) or speed,, between 2500-3800 rpm, the car seems to loose power when i use the throttle 30%-90% ..

It comes good past the 3500 area, but most of (normal) driving is in the range of 2500-3800 for me, see the problem?

Im not sure if its a tuning problem(timing) or something else. I can hold it in gear (eg 2nd, with the hold-gear-button) and boost it .. the boost gauge reads +5 or whatever, and you hear the turbo(1st problem) however the car seems to slow a fraction then slowly gains speed. If i allow it to drop back a gear or 2, it laggs (normal for an auto i guess) then takes off as i think it should- because dropping a gear or to the rpm is higher then 3500

I know its a 2nd hand car, 10yr old ect... but really starting to get to me..

please help (a noobie) :ermm:

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https://www.sau.com.au/forums/topic/320855-arhh-thoughts-one-noise-lag-rb20det/
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1.. start the car and look/hear for the leak possible manifold/turbo gasket i would replace al of them while your at it, manifold, turbo, exhaust.

2. replace all spark plugs, coilpacks, could be cas (dought it). try resetting your ecu.

ok, a few things. first of all, i can't hear any loud spooling noise. just sounds like a normal intake noise for a skyline.

secondly, the rb20 is a laggy engine, even in stock form. unlike the rb25, which will make full boost by about 2500rpm, the rb20 on the stock turbo won't make full boost until about 3500rpm. below that rpm you will have a somewhat slow car, and if you were up against a natro car, until you get above about 3500-4000rpm they will pull away quite easily.

also, i'm not sure if the r32 ecu has it, but if you are running up to 16psi on the stock ecu, you may be hitting an airflow pretection which is limiting the power you will make.

may also be worth checking the timing as if it is retarded you won't have as much down low.

i think your best bet would be to stick it on a dyno. that way you can properly hear any noises and also see what sort of power it makes as that will be the true indicator of any problems.

oh and the flutter isn't caused by the wastegate. that is either the bov, or if you don't have one, compressor surge, which is the air in the intercooler piping going back out through the compressor wheel of the turbo and slowing it down so you end up with more lag.

Thanks for heads up...

camera didnt really get the full sound....

Its a "re-chipped" ecu --- so fuel/boost cuts are removed, and maps slightly adjusted.

the wastegate flutter , i was being an idiot.. lol

but thanks, going to get my mech to check the timing..

Thanks for heads up...

camera didnt really get the full sound....

Its a "re-chipped" ecu --- so fuel/boost cuts are removed, and maps slightly adjusted.

the wastegate flutter , i was being an idiot.. lol

but thanks, going to get my mech to check the timing..

hard to tell these days. the guy i bought my 180sx off thought that the sound of the bov was the soundof the wastegate

Ok,

attached a video-2

http://www.youtube.com/watch?v=ZypFH3DehrI

&

http://www.youtube.com/watch?v=LjTXgZui-Y4

Thoughts ?

Notice the spike.. ?

The first (shorter) video is a better example.. ran out of road on the 2nd vid

--Spikes up to 16-17psi.. and drops

Edited by Blood

what sort of boost controller are you using, and where is it located?

if you have a manual boost controller and a fmic and have the boost controller hooked in off the line to the bov or something like that, then i'd say that is more than likely the issue. i had a spiking issue after i put my fmic on my 33.

or you may have an issue with the wastegate (or wastegate actuator) where it is sticking initially and then once the boost gets up to around 16psi it is able to free itself and it can drop to the lower boost. the same thing could be happening with the boost controller.

Its a tap type.

This is the current setup

If i open the tap, then it seems ok (to hold 9 psi 'ish)

Close it a little, it spikes as seen on video, and hold 7-9 psi....

and when the pressure drops, i back off and floor it again, the pressure spikes again to abotu 12-14psi

:) (see attached)

post-73266-1274234285_thumb.jpg

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