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Boost Problem....don't Know Whats Going On

improvin

By improvin,
in Engines & Forced Induction

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improvin Enthusiast

improvin

Posted
Posted

hey guys i've done the searches and still don't know what s going on. i just got my turbo hi-flowed and the boost rises freely. as soon as i put the foot down it flies past 1 bar. i took the bleed valve out and left it as stock setup and it goes to .8 bar for a split second and as the revs climb so does boost to 1 bar. i've checked lines i've made sure it fitted right. if i connect the wastegate to the bleed valve and the hose off the cooler to the bleed valve and block off the third line, winded up the boost the boost just climbs like it was on stock setup, as if it wasn't there. if i hook up the wastegate to the bleed valve and T piece the hose from the cooler and the third line then connect it up to the bleed valve it just flies to 1 bar and over. does anyone know what to do i want it to be set at 12 psi and hold. please need help

improvin Enthusiast

improvin

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yeah exactly as stated by craved i did that. the boost goes to .8 bar then as the revs climb so does the boost to 1 bar. now whether i set the bleed valve to 12 psi or close it off it does the same thing. it goes to .8 bar then climbs with the revs to 1 bar

Craved Grand Master

Craved

Posted
Posted

only other thing is that the wastegate cannot allow enough gas out to allow the lower boost setting

or

the wasegate is sticking and not opening fully to allow that boost reading.

.....

what sort of supporting mods do you have?

and does it hold at 14.7 psi once it gets there?

improvin Enthusiast

improvin

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okay i've got a intercooler, full exhaust and now the turbo....still working on getting a computer.

last night i changed the wastegate to my old one and now the boost goes to .5 bar and then slowly creeps to 1 bar with the revs.

the boost doesn't just sit at 14.7 psi it goes to whatever...it just free boost...it once when to 1.5 bar

hey thanks for your info craved but still doin my head in

you think its a good idea to change the wastegate to something else

improvin Enthusiast

improvin

Posted
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Posted

well the way i've hooked it up is from the

1. cooler hose->bleed valve->wastegate = it goes to .5 bar then when the revs climb so does the boost to 1 bar

2. cooler hose T piece with the other vacuum line->bleed valve->wastegate = i get free boost

with option 1 i turn winded up the bleed valve and it doesn't do anything it's like its not even there. it just does what is above at option 1. its the same for option 2 its as if the bleed valve is not even there

rob82 Mentor

rob82

Posted
Posted
well the way i've hooked it up is from the

1. cooler hose->bleed valve->wastegate = it goes to .5 bar then when the revs climb so does the boost to 1 bar

2. cooler hose T piece with the other vacuum line->bleed valve->wastegate = i get free boost

with option 1 i turn winded up the bleed valve and it doesn't do anything it's like its not even there. it just does what is above at option 1. its the same for option 2 its as if the bleed valve is not even there

Have you try just running wastegate pressure? As in cooler hose to wastegate. If so what happens then??

chrissso Proficient

chrissso

Posted
Posted

Try wiring your wastegate wide open. Or disconect the actuator from the wastegate flap so it's wide open. (internal gate right?) Then go for a drive. See what boost you get. If you still get a bar with the wastge wide open, then your waste gate isn't big enough. I had a little problem like this when I fitted a dump pipe and an air pod filter. My guess is the extra breathability of the combined dump and air pod meant that either the wastegate was too small, or the actuator wasn't opening the wastegate enough when it was full extended.

Fixed it with a Jaycar Independant electronic boost controller.

My max PSI was about 9, so I tuned the IEBC to run 9psi the whole way through the rev range for a flat boost curve. You would have to do the same for 14.7psi

I also found that after fitting another pod filter that was more restrictive, boost would start to creep up and then fall off at the top of the range.

hope this helps...

improvin Enthusiast

improvin

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hey thanks for the reply guys, craved i've changed all the hoses before i posted it and it doesnt change same shit. i'll try what chrisso said and disconnect the actuator thanks for the info mate. kyro if you could let me know about your mate with the sr much appreciated. the hiflow was done at JPC in thomastown in melbourne

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