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Boost Spike

shaun123

By shaun123,
in Engines & Forced Induction

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shaun123 Community Regular

shaun123

Posted
Posted (edited)

hey guys,

i recently changed my cat back exhaust (from a aftermarket 3" to a different 3"), left everything from there untouched (stock dump pipe). I was fiddling around to change my dump pipe and decided to leave it for another day as it seemed i needed to take the heat shield out.

In the process of trying to loosen some of the screws on the heatshield, i took off an earthing wire but then i put it back on when i gave up for the day..

my car has always held constant 0.5bar boost, now when i drive it, 5000+rpm or so, it spikes to 0.7bar boost? any reason why its doing this? any help appreciated...

The earth in question is circled red

21052010083.jpg

Edited by shaun123
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shaun123 Community Regular

shaun123

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but i still have my stock dump pipe, wouldnt this mean that no matter how big the catback exhaust was, it'd still only flow to the stock specs?

I used to have a aftermarket 3" system on it before anyway, and i just changed it to another aftermarket 3" system...

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lachlanw Veteran

lachlanw

Posted
Posted (edited)

its not a spike either

a spike is if you graphed it and the graph had a sudden rise then sudden drop eg a spike

and its normal

what are you worried about

and that earth has SFA to do with anything

Edited by lachlanw
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