VACUUM SEEMS LOW AT 5-7psi
09-28-2008, 12:11 AM
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Car: 1984 Firebird SE
Engine: 388 sbc, Brodix Track 1s
Transmission: turbo 350 transmission
Axle/Gears: 4.10 gears
VACUUM SEEMS LOW AT 5-7psi
You can see the specs of my motor in my sig listed below. I have total advance set at 36*, set idle mixture screws to 1 1/2 turns out and seems to run better between 1 - 1 1/8 turns out. PV on primary is 2.5 and 78 jets all around. Had the heads off recently to have them checked for cracks, new springs installed, re-surfaced and new head/intake and exhaust gaskets. Was having low vacuum before I did any of this also.
Maybe this is normal for my cam, anyone have any input?
Maybe this is normal for my cam, anyone have any input?
Last edited by mcbchild; 09-28-2008 at 12:11 AM. Reason: updated
09-28-2008, 12:17 AM
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Car: 1984 Firebird SE
Engine: 388 sbc, Brodix Track 1s
Transmission: turbo 350 transmission
Axle/Gears: 4.10 gears
Re: VACUUM SEEMS LOW AT 5-7psi
I also set the primary throttle blades to .040 below the transition slot.
09-28-2008, 12:39 AM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
That's a heap of duration, so I wouldn't call it excessively low.
BTW, it's inch-Hg, not psi.
BTW, it's inch-Hg, not psi.
09-28-2008, 08:01 AM
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Car: 1984 Firebird SE
Engine: 388 sbc, Brodix Track 1s
Transmission: turbo 350 transmission
Axle/Gears: 4.10 gears
Re: VACUUM SEEMS LOW AT 5-7psi
So with that duration it's about in the correct range?
BTW, I knew it is in inch-Hg and don't know why I put in psi. Guess I was thinking compression.
BTW, I knew it is in inch-Hg and don't know why I put in psi. Guess I was thinking compression.
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