Negative boost on Gauge??????
Negative boost on Gauge??????
Author
Discussion

klousehouse1

Original Poster:

22 posts

189 months

Monday 28th February 2011
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Guys,
I am assuming that if i get negative boost on the boost gauge that something is connected wrong???
First Turbo car!!!And my first Nob......excuse me for being green.

Also while im on, tick over is about 950, seems a bit high? If so how can i adjust...adjust screw and turn ignition on and off 10 times???

Thanks for any advice up front

The devil

2,152 posts

212 months

Monday 28th February 2011
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No, they do show negative as well
I would just check your throttle cable is not tight after that it seems you shouldn't adjust it

SimonJW

779 posts

266 months

Tuesday 1st March 2011
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Mine runs at -0.5 regularly when 'normal running' and not 'progressing'.

joust

14,622 posts

288 months

Tuesday 1st March 2011
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Negative pressure is perfectly fine, as it's how an engine works smile

When the engine in sucking in air (i.e. without a turbo), the inlet manifold will be under negative pressure to enable the air to enter from outside. Until the turbo is spinning up enough and therefore "pushing" as much air in as the engine needs on a down stroke, the pressure will be negative to zero.

From idle to around 3000ish rpm this will generally be the case.

Once the turbos get going and start pushing more air in than the engine needs from it's own downstroke, then you'll get positive pressure.

Ergo, if it's negative when you have no or part throttle, and positive when you have lots of throttle, it's fine.

J

The devil

2,152 posts

212 months

Tuesday 1st March 2011
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Yep
What he said
I'm just a sparky

klousehouse1

Original Poster:

22 posts

189 months

Tuesday 1st March 2011
quotequote all
Thanks Guys,
That makes perfect sense now someone has explained it.Thanks

What is max standard boost for a standard 3GTO?

jamescmr2

713 posts

208 months

Tuesday 1st March 2011
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klousehouse1 said:
Thanks Guys,
That makes perfect sense now someone has explained it.Thanks

What is max standard boost for a standard 3GTO?


from memory it is about 0.7bar

cheers

verba1

628 posts

197 months

Wednesday 2nd March 2011
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jamescmr2 said:
from memory it is about 0.7bar

cheers
.

When the car is idling my boost gauge shows i would say - 0.7 .

Unfortunately , i could not check the + 0.7 today as i took it out for a drive today especially as they have reduced the speed limit to 30 MPH on the A40 wink

The RPM needle sways a liitle bit on idle.. is that normal ?




joust

14,622 posts

288 months

Wednesday 2nd March 2011
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verba1 said:
The RPM needle sways a liitle bit on idle.. is that normal ?
TADTS

verba1

628 posts

197 months

Wednesday 2nd March 2011
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joust said:
TADTS
Ta Justin

The devil

2,152 posts

212 months

Saturday 2nd April 2011
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