Strange Boost Levels.......

[YCOPY]

Hi All,

I have a95 r33,manual,FMIC,exaust,and apexi pod filter.

I have just done the mod of making the boost selonid connectedt to a switch so i can run high or low boost.

i have a little problem,when i have the switch off (so the car should run 5psi) my autometer gauge says 5psi and the factory gauge in the dash reads what i belive is 5psi (the mark between 0-7) but when i flick the switch the autometer gauge reads 8-9 but the dash stays the same... (half 0-7)

i have the autometer plumbed into the line from the selonid to the inlet piping,so i dont get a vacum reading just boost.

i have just had the 100,000kms service done and the car seems to be lacking in power...when i had the boost selonid still as factory the car wasnt hitting the second stage.....

im at a loss as to whats going on here..

maybe a small boost leak...

can anyone help??

[rs73]

This has been covered so many times in this forum if you do a search on factory boost gauge.

The factory boost gauge is not in psi, but in Hgmm. (mercury).

At +7 Hgmm is equal to 1 Bar or around 14psi. Does this answer your question straight away?

How high did u rev your car? The 2nd stage of factory boost solenoid doesn't really kicks in until about 5000rpm+ Again with a car that's travelled 100,000km chances are there's a brittle/cracked hose somewhere, hard to find a real pain when there's so many hoses in there. Or even the boost solenoid has stopped working properly due to getting dirty or just getting old. You'll have to check everything and clean it if possible.

[YCOPY]

i have been having a read of the other posts,the prob is that there is no difference between my low boost and high boost on the dash gauge,but there is a difference on my autometer gauge.

the car was taken to redline,its weird,there is no performance difference between lo and high yet the autometer says there is a boost increase when i flick it up.

before i took the car for its service the second stage of boost made a good difference...but yer now the car just feels like its being restricted....

i will give it a go of cleaning and checking all hoses and the selonid,i also might try and put a duel stage boost controller in and see if that has a pleasing effect....

thanks

SC

[Links]

Check that you wired it up correctly..

You should def feel a difference between 5psi and 8psi..

[rs73]

I agree. 5 & 8 psi should somehow make a bit difference. Did you try both on dyno for reading and on the street test drive? Most installation I saw is actually blocking off one of the hoses from solenoid. Better still a lot people removed the solenoid out of the whole scene and solely rely on the boost controller.

[YCOPY]

yer it is wired up correctly,if i leave it switched off the autometer gauge stays at 5psi,and when i flick it up it goes to 8-9psi...

its the gauge in the dash cluster that dosent move when i flick the switch..(it moves in general so its not broken)

i havent had the car on a dyno at all. just street testing.

there is somthing that just dosent feel right....

i think i will go over it tonight when i get home and see what i find...

[rs73]

Maybe the autometer boost gauge sensor was placed at the wrong location?

[YCOPY]

i thought that too,i have a second boost gauge that i might just temp mount in a different location and see if there is a difference.