Normal Vacuum Read?
05-13-2010, 06:39 AM
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Normal Vacuum Read? So I have had my rear-mount system installed for about three weeks, and was curious as to what my boost/vac gauge should read for the vacuum under idle and under consistent cruising? My vacuum reads about 20 at idle at around 16-17 under consistent cruising speed at around 45 MPH (give or take)... what's normal?
Also, my set-up is set for 5 lbs, but is only boosting up to 4 lbs according to my gauge... what could be the issue here? Thanks for any help that you guys can provide, because I am very new to the turbo game and want to know this stuff.
Also, my set-up is set for 5 lbs, but is only boosting up to 4 lbs according to my gauge... what could be the issue here? Thanks for any help that you guys can provide, because I am very new to the turbo game and want to know this stuff.
05-13-2010, 07:07 AM
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The vacuum at idle or low RPM's will become lower as the cam you install becomes larger. My 232/240 for instance has 12 lbs. at idle. I would guess you have a stock or very small cam and your readings sound normal. As far as your boost problem I'll let the turbo guys help you there.
05-13-2010, 07:15 AM
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Where is it referance at. thats barley any psi off the gate. what spring u have in the gate? and make sure the turbo spins freely while the car is running. Double check for leaks also. Your vac seems odd though. I seen rearmounts with ls6 cam have better vac than that. it sat around 15 vac at idle.
05-13-2010, 08:38 AM
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That seems normal to me with a stock motor, when your running low boost it's not uncommon to see a difference, could be a lot of factors your reference point, springs aren't always exact, gauge could be slightly off.
When you get into the throttle does it shoot up to 4lbs and hold?
When you get into the throttle does it shoot up to 4lbs and hold?
05-13-2010, 12:50 PM
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That seems normal to me with a stock motor, when your running low boost it's not uncommon to see a difference, could be a lot of factors your reference point, springs aren't always exact, gauge could be slightly off.
When you get into the throttle does it shoot up to 4lbs and hold?
When you get into the throttle does it shoot up to 4lbs and hold?
05-13-2010, 09:17 PM
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I would turn it up, but it is set at 5 lbs right now and it is only boosting to 4 lbs. Plus, my car isn't tuned yet. I am struggling with who I will have tune it.
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05-14-2010, 04:43 AM
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So I have had my rear-mount system installed for about three weeks, and was curious as to what my boost/vac gauge should read for the vacuum under idle and under consistent cruising? My vacuum reads about 20 at idle at around 16-17 under consistent cruising speed at around 45 MPH (give or take)... what's normal?
Also, my set-up is set for 5 lbs, but is only boosting up to 4 lbs according to my gauge... what could be the issue here? Thanks for any help that you guys can provide, because I am very new to the turbo game and want to know this stuff.
Also, my set-up is set for 5 lbs, but is only boosting up to 4 lbs according to my gauge... what could be the issue here? Thanks for any help that you guys can provide, because I am very new to the turbo game and want to know this stuff.
05-15-2010, 08:38 PM
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Hes a tunning mother (Fu#% er) LOL
And he wont stop till your ***** perfect! 