boost gauge question - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

scotland200sx · 09-29-2005, 12:48 PM

i have just fitted a boost gauge,

when the car is idling is the reading suppose to be -6?

i took it for a run and when the boost kicks in i get a + reading.

i take it that 0 on the gauge is the moment the boost comes on?

sr240mike · 09-29-2005, 12:57 PM

Im around -18 at idle.

Andrew Bohan · 09-29-2005, 01:43 PM

-20 is ideal. most people are around -18 or -19 at idle.
you have a vacuum leak.

ALTRNTV · 09-29-2005, 02:17 PM

When I had my SR back then, I was always at -18 at idle. Yes, 0 is when boost starts, or actually 1.

scotland200sx · 09-29-2005, 02:27 PM

Quote:

Originally Posted by i'm driftaholic

-20 is ideal. most people are around -18 or -19 at idle.
you have a vacuum leak.

how do i find a vaccum leak?

what symtoms can a vaccum leak cause?

its a digital gauge so i might have a bad connection

Eternal_240Sx · 09-29-2005, 02:30 PM

you should probrably check your vaccum lines and intercooler piping and make sure there isnt any are leaking. Or get a can of Carb cleaner and just start spraying areas where you think may be leaking, your idle will fluctuate if you spray into the leak.

scotland200sx · 09-29-2005, 03:31 PM

Quote:

Originally Posted by Eternal_240Sx

you should probrably check your vaccum lines and intercooler piping and make sure there isnt any are leaking. Or get a can of Carb cleaner and just start spraying areas where you think may be leaking, your idle will fluctuate if you spray into the leak.

cheers!!

the digital boost gauge screen layout is like -0.0

how would it show double digit numbers?

ill check for vaccum leaks

420sx · 09-29-2005, 05:17 PM

you got to be fuckin kidding me..... when it idles it should be at 0.

Var · 09-29-2005, 05:18 PM

boost guage should read 0, but a vacuum/boost guage should read negative 10 or around there. cause it's in psi not inches of mercury

420sx · 09-29-2005, 05:55 PM

hmm....maybe my boost gauge's teflon line got a cut/hole somewhere. cheap crap....

Yoshi · 09-29-2005, 06:00 PM

Quote:

Originally Posted by Var

boost guage should read 0, but a vacuum/boost guage should read negative 10 or around there. cause it's in psi not inches of mercury

Var, -10???
maybe u got a leak too! LOL!

I was always told that -20 is idea, but -15-20 is prolly the realm of reality.... I hover around -17 at operating temp.

*NemeGuero* · 09-30-2005, 12:26 AM

I'm KA-T and I'm about 18,19 PSIat idle.. don't know if it's diff for sr

scotland200sx · 09-30-2005, 04:04 AM

just went to my local performance car garage (www.crdracing.co.uk)

they said that -.5 at idle is about right(0 in an ideal world). if its at -20 then there is somthing wrong with the compression in the engine or the connection to the boost gauge is in the wrong place. i still get a reading of 7 when at full boost witch is correct for a stock sr20det.

nrg · 09-30-2005, 04:31 AM

vaccum reading depends on what has been done to the engine. with upgrade cams and head job, the vaccum presure reading on my friend's car was at 10 IN HG. My stock sr20 reads 18 IN HG.

scotland, i think you're confused from BAR and IN hg reading. your -.5 bar sounds about right.

the head · 09-30-2005, 08:05 AM

Quote:

Originally Posted by scotland200sx

just went to my local performance car garage (www.crdracing.co.uk)

they said that -.5 at idle is about right(0 in an ideal world). if its at -20 then there is somthing wrong with the compression in the engine or the connection to the boost gauge is in the wrong place. i still get a reading of 7 when at full boost witch is correct for a stock sr20det.

what unit of measure is your gauge in?

the numbers you are recieving here are for boost PSI and vor vacuum IN/HG (inches of mercury) sounds like your system is running on somthing else (BAR possibly)

Yoshi · 09-30-2005, 10:18 AM

Quote:

Originally Posted by scotland200sx

just went to my local performance car garage (www.crdracing.co.uk)

they said that -.5 at idle is about right(0 in an ideal world). if its at -20 then there is somthing wrong with the compression in the engine or the connection to the boost gauge is in the wrong place. i still get a reading of 7 when at full boost witch is correct for a stock sr20det.

sorry doode

like the head & nrg said, we measure mostly in PSI (positive/boost), and Hg (vacuum). You being in scotland, yet another awesome country pillaged by the brits :P, i'm pretty sure your shop is giving you measurements in BAR.

I think .5 bar = -14.77Hg

So that's about the right ballpark.
Give us a pic of your boost gauge if u want to be sure

Var · 09-30-2005, 02:19 PM

Quote:

Originally Posted by Yoshi

Var, -10???
maybe u got a leak too! LOL!

I was always told that -20 is idea, but -15-20 is prolly the realm of reality.... I hover around -17 at operating temp.

meh..what does it matter now. i dont even own a 240. LOL.?? i dunno man. i remember my Profec E-01 being around -10, but maybe it was 18. The display is hard to see during the day.

scotland200sx · 10-01-2005, 03:16 PM

Its in BAR

sorry for the confusion.

09-29-2005, 12:48 PM	#1
scotland200sx Join Date: Sep 2005 Location: scotland Posts: 19 Trader Rating: (0) Feedback Score: 0 reviews	boost gauge question i have just fitted a boost gauge, when the car is idling is the reading suppose to be -6? i took it for a run and when the boost kicks in i get a + reading. i take it that 0 on the gauge is the moment the boost comes on?

09-29-2005, 12:57 PM	#2
sr240mike Zilvia FREAK! Join Date: Apr 2004 Location: California, Norcal biiaatch Posts: 1,185 Trader Rating: (0) Feedback Score: 0 reviews	Im around -18 at idle. __________________ TWO IN THE COOT, ONE IN THE POOT

09-29-2005, 05:17 PM	#8
420sx Post Whore! Join Date: Jun 2004 Location: Texas Age: 42 Posts: 3,960 Trader Rating: (0) Rides Gallery: 420sx Feedback Score: 0 reviews	you got to be fuckin kidding me..... when it idles it should be at 0. __________________ hydropgrahics! ls1......

09-29-2005, 05:18 PM	#9
Var Post Whore! Join Date: Sep 2003 Location: Norcal Age: 43 Posts: 5,032 Trader Rating: (0) Rides Gallery: Var Feedback Score: 0 reviews	boost guage should read 0, but a vacuum/boost guage should read negative 10 or around there. cause it's in psi not inches of mercury __________________ Hi

09-29-2005, 05:55 PM	#10
420sx Post Whore! Join Date: Jun 2004 Location: Texas Age: 42 Posts: 3,960 Trader Rating: (0) Rides Gallery: 420sx Feedback Score: 0 reviews	hmm....maybe my boost gauge's teflon line got a cut/hole somewhere. cheap crap.... __________________ hydropgrahics! ls1......

09-29-2005, 01:43 PM	#3
Andrew Bohan Post Whore! Join Date: Apr 2003 Location: Ohio Posts: 8,331 Trader Rating: (2) Feedback Score: 2 reviews	-20 is ideal. most people are around -18 or -19 at idle. you have a vacuum leak.

09-29-2005, 02:17 PM	#4
ALTRNTV Post Whore! Join Date: Mar 2003 Location: Western Conference Posts: 9,429 Trader Rating: (0) Feedback Score: 0 reviews	When I had my SR back then, I was always at -18 at idle. Yes, 0 is when boost starts, or actually 1.

09-29-2005, 02:30 PM	#6
Eternal_240Sx Zilvia Addict Join Date: Dec 2002 Location: norcal, bay area Age: 41 Posts: 674 Trader Rating: (1) Feedback Score: 1 reviews	you should probrably check your vaccum lines and intercooler piping and make sure there isnt any are leaking. Or get a can of Carb cleaner and just start spraying areas where you think may be leaking, your idle will fluctuate if you spray into the leak.

09-30-2005, 12:26 AM	#12
NemeGuero No more nissan. Join Date: Jan 2003 Location: RAIN, Washington. Age: 40 Posts: 8,132 Trader Rating: (10) Rides Gallery: NemeGuero Feedback Score: 10 reviews	I'm KA-T and I'm about 18,19 PSIat idle.. don't know if it's diff for sr

09-30-2005, 04:04 AM	#13
scotland200sx Join Date: Sep 2005 Location: scotland Posts: 19 Trader Rating: (0) Feedback Score: 0 reviews	just went to my local performance car garage (www.crdracing.co.uk) they said that -.5 at idle is about right(0 in an ideal world). if its at -20 then there is somthing wrong with the compression in the engine or the connection to the boost gauge is in the wrong place. i still get a reading of 7 when at full boost witch is correct for a stock sr20det.

09-30-2005, 04:31 AM	#14
nrg Zilvia FREAK! Join Date: Mar 2004 Location: CA Age: 40 Posts: 1,571 Trader Rating: (1) Feedback Score: 1 reviews	vaccum reading depends on what has been done to the engine. with upgrade cams and head job, the vaccum presure reading on my friend's car was at 10 IN HG. My stock sr20 reads 18 IN HG. scotland, i think you're confused from BAR and IN hg reading. your -.5 bar sounds about right. __________________ driftingisgay.com

10-01-2005, 03:16 PM	#18
scotland200sx Join Date: Sep 2005 Location: scotland Posts: 19 Trader Rating: (0) Feedback Score: 0 reviews	Its in BAR sorry for the confusion.