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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
-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
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
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
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
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
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.