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Boost Creeping Higher And Higher!

604cefiro

By 604cefiro,
in Engines & Forced Induction

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604cefiro Contributor

604cefiro

Posted
Posted (edited)

Hey guys,

A few months ago, my car was running a 8PSI spring in the external Tial wastegate. The Apexi AVCR was set to 1 Bar. I started to notice that the DEFI gauge would start registering higher and higher numbers. So recently I dropped a 1 Bar spring into the Tial, and turned OFF the AVCR, to see if it would stop boost creep since Apex AVCR are known for spiking.

Now in theory, the car shouldn't boost higher than 1 Bar since the external gate has a 1 Bar spring correct?

After I put the 1 Bar spring in, the car started to misfire and go bang bang bang at high boost high RPM ( view thread here: http://www.skylinesaustralia.com/forums/in...howtopic=127752 )

Ontop of the misfiring problem, my DEFI gauge started to show higher and higher numbers. First it was 1.2 bar, then 1.25, then 1.3, then 1.35, and now it shows 1.5!!

Im also aware that DEFI boost gauges sometimes show higher numbers, but being off by 0.5 bar is a little much.

Anyone have a clue what's going on???

My RB25 is internally stock, but i do have supporting mods for the power i dyno'd at.

Another thing is that i feel that my 440 Injectors are maxing out. Will be going much bigger in a few weeks.

Thanks for the help guys.

Edited by 604cefiro
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r33_racer Grand Master

r33_racer

Posted
Posted (edited)

You do have the lines connected properly right? I had my avcr hooked up arse about in that it will still setup for a internal gated turbo, not external and the boost kept spiking randomly all over the place.

Or as R31Nismoid said the lines may be damaged or have holes or splits in them.

side note *(Not to be rude, but 440cc injectors could not support your 400whp, that means maxed out your making 440hp @ the fly (give or take 10-15hp), does your driveline only use 40hp, how come your drivetrain is more hp efficient then mine? Theoretically you could only make about 360whp max with those injectors. Ofcourse they could be freakish and flow way more then their stated rating.) I know weve all spoken about this before, so i apologise for it being off track.

Edited by r33_racer
BHDave Grand Master

BHDave

Posted
Posted

It sounds like either a restriction in the wastegate or outlet or a problem in the plumbing to the wastegate, either blocked or split line.

I'd remove the avcr from the loop completely and replace the line between your boost signal and wastegate as a start. Also check that the pipe off your wastegate hasn't been crushed under the car somehow.

r33_racer Grand Master

r33_racer

Posted
Posted
i worked out his power reading... he lives in the US :D

they are a lot different. So its closer to our... 260rwkw

Well that makes sense then. Cause the mods and power just dont add up!

Maybe check the valve itself in the gate and see if its working properly, or maybe that you didnt damage the neoprene seal in the top part of the gate when you or whoever changed over the spring.

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