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Old 03-23-2004, 09:04 PM   #1
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Default Boost Gauge Question

Hey all,

Just was wonder what is normal boost under WOT?
And how accurate is that gauge? Anything that can throw it off?

I've noticed my boost is normally 17.5kPa (2.5 psi) or +1/4 on the gauge.
But sometimes it will do upto 26.25kPa (3.8psi) or +3/8s on the gauge, and kinda spike like it'* trying to get to 35kPa (5 psi) or +1/2 the gauge.

Is there anything to do (while driving) that can increase the boost? or at least what is displayed? I noticed that if you have the A/C on sometimes when idle the boost gauge moves.
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Old 03-23-2004, 09:09 PM   #2
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You're screwy. I think on the Series II you should see about 6-7 psi at WOT in gear. Series 1 goes to about 8-9 stock.
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Old 03-23-2004, 09:27 PM   #3
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Boost control solenoid (lookit me tryin to talk the talk :P )

Sounds like Merlin needs a smalley pulley.
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Old 03-23-2004, 09:33 PM   #4
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BCS and pulley. The recipe for success Might only be an indication prob though. I'd be looking at the MAP sensor and tubing. Maybe a full top-end inspection is in order?
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Old 03-23-2004, 11:48 PM   #5
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Quote:
Originally Posted by willwren
BCS and pulley. The recipe for success Might only be an indication prob though. I'd be looking at the MAP sensor and tubing. Maybe a full top-end inspection is in order?
Ok... I know little about engines and even less about this magical supercharger...
All I know is.... I like boost...

This BCS.. boost control solidnoid.... controls the boost? How can I tell if it'* faulty or not? Or do I need to upgrade it? (like I would the pulley)

How do I check the MAP sensor ... and tuibing?
Should I have a mechanic do this for me? (please note I'm really ticked off at the local GM shop right now, so would a non GM person know what to look for?)

Full top end inspection? That sounds expensive (even if nothing is wrong).
"Full" "top end" and "inspection" just screams $$$..... and again... same questiion as above... should it be GM only or not to do this?
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Old 03-24-2004, 12:02 AM   #6
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Just because I can.... here'* a photo of my boost gauge.... lableled....
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Old 03-24-2004, 12:26 AM   #7
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Is this puppy on tight?




Before I did any mods this is what my boost guage was reading at WOT on my 1999 SSEi.
I know it'* blurry, but you can tell it'* way down there (not in vacuum).




Just follow all the vacuum lines around the engine compartment and make sure they are all snug on the connectors. Also make sure none are hard, brittle, cracked, etc... If any need to be replaced don't worry about $$$ -I bet you could redo all the standard vacuum lines for under $10 Canadian and in under 20-30 minutes (just do one at a time though). Good luck.
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Old 03-24-2004, 12:34 AM   #8
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Hrm.... she seems like she has lots of power....
Lets assume that the gauge is correct, and it'* not the full boost.... how much HP am I losing?

The reason I ask is because she doesn't seem slow at all (bear in mind she is my only SCed 3800) hehe... so any boost is better then none.
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Old 03-24-2004, 02:27 PM   #9
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Get some one to feather the throttle while you look at the boost gauge, can you see it actuate to dump boost? Has the gauge always ran to this level or is this a drop in the gauge since you bought it?
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Old 03-24-2004, 08:02 PM   #10
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Quote:
Originally Posted by PontiacDad
Get some one to feather the throttle while you look at the boost gauge, can you see it actuate to dump boost? Has the gauge always ran to this level or is this a drop in the gauge since you bought it?
Not sure what you mean.... "actuate to dump boost".. where/what am I looking for?

Actually the boost have improved since I got it.
When I took her home from T.O. she was only boosting +1/8th.
I had all new gator belts put on her in Sept... a complete tune up too. She then boosted easily to +1/4 and I could fell a difference.
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