Boost gauge readings?

[interloper393]

Hi guys, just fitted a blitz boost gauge, what shouls the reading be at idle? the dial arm had fell off in the post so had to pop it bck on, im reading a negative value on idle.. also what should the readings be through the rev range plz, iv got stock twins at the moo..

cheers
Craig

[nikp]

It should be a negative value at idle. The throttle plates are shut, and the only air coming in is via the idle valve, so it\'s \'sucking\' air, and causing a vacuum. Can\'t remember the exact values though - but in the region of 450mmHg is roughly where it should be.

On stock twins, your boost readings should be 10-8-10psi (0.7-0.55-0.7bar).

hope that helps.

[Jono FD3]

That is correct, you should hav a vaccum reading at idle, then a pressure reading when on boost.

The readings on stock twins is normaly: 0.8 bar to about 3500rpm, Slight drop between 3500 & 4500 RPM (0.7 bar), then when the second turbo kicks in at 4500 it should return to 0.8.


Jono

[nikp]

Jono, those I believe are a bit high for purely stock. Depends whether anything has been done mod wise. Exhaust, induction, etc, etc

[interloper393]

iv got an exhaust and filters, plus a hks boost controller?? dunno why that was fitted lol.. cheers guys wasnt sure is i stuck the needle on the wrond bit lol.. i`ll double check the readings today, i broke the check valve coming from the plenum so im sure my 2nd tuby may got go lol.. fixed with superglue

[Jim_rx7]

I\'m gonna have a good look at my readings tomorrow. Never really paid attention to what is was boosting too.

[ro284]

iI think the procedure to test the twins is cruse along at 30 in third gear, then give it some welly up to 70 or 80 without chaning up, all while watching where you are going and looking at the gauge
Good luck Bob

[interloper393]

, all while watching where you are going and looking at the gauge
Good luck Bob

have this covered im building a custom 1 off gauge holder :yes