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Tapping into vacuum line Question


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I installed my blitz turbo timer with the built in boost gauge by an auto electrician and he t piece off the hose between the inlet manifold and the fuel pressure regulater.

i read off some document that it not a good idea to plumb it there. is this true and which other vacuum line can I tap into to get boost reading and where its located?

this is what the document state: do not tap into the hose which runs from the inlet manifold to the fuel pressure regulator, or the wastegate supply line. If you loose pressure in these two hoses due to crimping or the hose blowing off, you risk killing your engine.

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I installed my blitz turbo timer with the built in boost gauge by an auto electrician and he t piece off the hose between the inlet manifold and the fuel pressure regulater.

i read off some document that it not a good idea to plumb it there. is this true and which other vacuum line can I tap into to get boost reading and where its located?

this is what the document state: do not tap into the hose which runs from the inlet manifold to the fuel pressure regulator, or the wastegate supply line.  If you loose pressure in these two hoses due to crimping or the hose blowing off, you risk killing your engine.

Absolutely correct, it is not a good idea. I would like to tell you the best place to plumb a boost gauge, but you haven't old us what engine you have. So I can't.;)

PS; Why do people not fill in their profile? That way we wouldn't have to keep asking.

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the best place to tap your boost meter into is the line between the inlet manifold and the fuel pressure regulator. it works in the opposite to what you have been told because at idle you are producing more vacuum than at flat chat because the throttle butterfly is closed

works like this

IDLE, low pressure(more vacuum)=low fuel pressure(less fuel)

wide open throttle,high pressure(less vacuum)=high pressure(more fuel)

once your into the positive pressure or boost it holds the pressure regulator closed by putting positive pressure behind the diaphram

if a hose were to blow off when under boost you will have a problem weather it is your pressure reg hose or your pcv valve hose

thats as simple as i can explain it, i hope it helps you out

if you are still confused PM me and ill explain it a bit clearer

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the best place to tap your boost meter into is the line between the inlet manifold and the fuel pressure regulator. it works in the opposite to what you have been told because at idle you are producing more vacuum than at flat chat because the throttle butterfly is closed

works like this  

IDLE, low pressure(more vacuum)=low fuel pressure(less fuel)

wide open throttle,high pressure(less vacuum)=high pressure(more fuel)

so if you bleed pressure off the fuel pressure reg(give it less vacuum) it will actualy give you higher fuel pressure because it is effectivly sencing more load on the engine(even though there isnt)

you will still lean out from having unmetered air being added after the air flow meter(s)

thats as simple as i can explain it, i hope it helps you out

if you are still confused PM me and ill explain it a bit clearer

are you trying to say do as what the statement state

even "sydneyboy" said is not a good idea to tap it into the line between the inlet manifold and the fuel pressure regulator

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Sup Godzil_R,

Some peoples don’t like to tee between the plenum and fuel reg, cus the chance of one of the connections popping off, surly a] you shouldn’t have the issue in the first place, if you secured them b] what stopped it popping off before you teed in? Two extra joins, and a slight "reservoir " effect, with all the air in the line, between gauge and tee ( assuming not digital gauge)

That said, Id use maybe the std map sensor line, or one of the many at the back of the engine... I guess even tapping your own, into the "runner crossover collector" thingo

Check and triple check all connections =PK

^^

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Q for GeeTR or anyone that know da answer, if the chance it did pop off and i didn't know of it,is there any noticable sign beside looking at the gauge(as i said its a tt with the built in digital gauge and it mounted low so i can't really see it) and will there be any damage to engine?

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ok i was a bit unclear

if you have a vacuum leak anywere after the throttle butterfly you will get a manifold pressure change no matter were you take your reading from

so if you have a vacuum leak in your map sensor line, this will also affect you fuel pressure regulator because manifold pressure has changed

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i dont suppose you had a look at the instructions that came with your blitz products. i know its all in japonese but take a look at some of the diagrams included and look were they say it should be

i have the instructions to my boost meter right in front of me. it is also a blitz product and it has a nice little diagram of were you place the T peice suplied with the product and it is exacly were the information is telling you not to put it

there is a picture of a fuel rail with four injectors in front of it and on the end of that fuel rail there is a fuel pressure reg with a vacuum line coming off it. the vacuum line has a circle around it and there is an arrow going to a nother diagram of the T piece being put into that vacuum line

im just wondering why people would think that a company like blitz would tell them the incorrect way to set up their pruduct

it is not a fluke because this is also what i have been taught

if im wrong im keen to hear other peoples oppions

has anyone else been taught a different way

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DRFTR33 its not that blitz would tell people to put it in an incorrect position, its more than some people dont wish to run the risk, saying that my gauge is plumbed into the stock boost gauge with a t peice,

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i dont suppose you had a look at the instructions that came with your blitz products. i know its all in japonese but take a look at some of the diagrams included and look were they say it should be

i have the instructions to my boost meter right in front of me. it is also a blitz product and it has a nice little diagram of were you place the T peice suplied with the product and it is exacly were the information is telling you not to put it

there is a picture of a fuel rail with four injectors in front of it and on the end of that fuel rail there is a fuel pressure reg with a vacuum line coming off it. the vacuum line has a circle around it and there is an arrow going to a nother diagram of the T piece being put into that vacuum line

im just wondering why people would think that a company like blitz would tell them the incorrect way to set up their pruduct

it is not a fluke because this is also what i have been taught

if im wrong im keen to hear other peoples oppions

has anyone else been taught a different way

the instruction doesn't have a diagram showing where to T off the vacuum line, that why im unsure

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any1 know where the standard boost control solenoid is located on an r32 gtr and what it looks like. is it silver in colour and has a stick on it reading pcv valve (is that the solenoid)

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I tee'd mine into the hose that goes to the stock boost gauge..

its a little black box near the firewall on the drivers side.

is that a little black box mounted on the firewall.. and there is an electrical connection on one side and a hose on the other side of the black box?

i got a yellow hose..

should i T my bost gauge in there?

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