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Richy_Boy
23-07-2001, 13:44
I need help! Had my car RR'd today, and it seems to pi$$ the boost out when holding high revs.. The chappies said it could be:
1) My dump Valve being the wrong side of the IC, and therefore seeing a higher boost level
2) My IC being ****e!
3) Small gerbals in the works...

I'm thinking 3 atm, but what do you all think?
Its hits 15psi, but then falls abck off to 10psi.. and any respectable revs...

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Rich

200 to 210 BHP @6000 rpm
S13 J reg Graphite Grey - ND200, Koni Adj., 17" wheelz, dropped. Broken.

Clong
23-07-2001, 14:22
Someone correct me if i am wrong, but this boost drop off is common when running higher that standard boost through the original intercooler (i assmue u r still runinng the original intercooler). It's too restrictive and doesn't allow air to flow quick enough at the higher rev range, hence the boost drops off. Thats why most of the chaps on this site run upgraded coolers (including me).

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1990 Blue S13
Mongoose 'zorst
K&N, ND Boost upgrade, Saab FMIC.`

[This message has been edited by Clong (edited 23-07-2001).]

Stuymac
23-07-2001, 14:48
Yup, sounds like boost drop off.

If you are still running std turbo and IC, the air coming from the turbo can not be cooled enough. The air from turbo gets very hot, and its the intercoolers job to cool the gasses down, however, the std IC can only do this to a certain extent, and after a few seconds of boost becomes hot. As hot air is less dence than cool air you lose boost pressure.



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Stu

DIY T3(knackered), dented front wing, FMIC, but need more power http://ubbpics.rsoc.co.uk/8090936541.gif !!!

Mannie
23-07-2001, 14:48
I get the same drop in boost through my Standard Intercooler.

I've got a bleed valve fitted which hits 14.5psi when I boot it but slowly drops down into the low 'teens.

Pretty sure its the Intercooler that lets it down.

Richy_Boy
23-07-2001, 17:53
Splendid! cheers chaps, just what I was hoping to hear.. SAAB breakers.. here I come!! lol

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Rich

200 to 210 BHP @6000 rpm
S13 J reg Graphite Grey - ND200, Koni Adj., 17" wheelz, dropped. Broken.

Nathan_200sx
24-07-2001, 09:15
Are you useing a bleed valve or uprated actuator? if it's an actuator you may want to check that the diaphram isnt split or leaking, my old one used to drop from 18psi to 12psi with a leak.

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Nathan
Red S13 Mongoose, K&N T3 280ish BHP http://www.3dpcgames.com/cwm/s/cwm/cwm/evil2.gif
Empty bank account

Richy_Boy
24-07-2001, 12:08
Sent u a mail Nathan, but I have a whole with a thread in it, in the side of my actuator. Should this have a bolt in it? :\
I have screwed one in for the minute, but this could explain 1/2 the reaso why I was loosing boost..?... maybe..

I also have a leak from my Turbo. To me it loks like quite a lot of oil, but it always does doesn't it? But it is also makeing a raspy noise like the exhaust or turbo manifold is leaking.. could this explain the oil? took it to a mechanic and he suggested I took it to Nissan! Think he got scared!

Any help.. would stop me worrying...


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Rich

200 to 210 BHP @6000 rpm
S13 J reg Graphite Grey - ND200, Koni Adj., 17" wheelz, dropped. Broken.