If the TB is opened up a bit, vacuum runs up to around 20-25in. When I
release the throttle to let the rpm drops back to idle, the vacuum drops
down to around 5-8in., then slowly chokes itself down to around 5in., and
then the engine stalls. It will sit and idle at a smooth 600-650rpm (aside
from the choppiness of the cam), and holds just about a dead on 11.25in. of
vacuum, and doesn't deviate more than .25in.
I did reuse the old TB gasket, but it was only on for around 2Kmi. and it
looked ok. Guess I'll try cutting a new TB gasket and see if that helps.
Any other ideas would be appreciated too.
From: SEMIHEMI01@aol.com [mailto:SEMIHEMI01@aol.com]
Sent: Saturday, June 02, 2001 11:40 AM
Subject: Re: DML: Vacuum Help Please
Sounds like you have a vacuum leak somewhere. Unless you put in a cam
with a monster amount of overlap. Your vacuum should not have changed that
much. Even with a SC'er I still pull 18-19 inches at idle, same as before
installation. I pull 11 inches at hiway speed unless I'm accelerating.
SEMIHEMI01@AOL.COM (Bill C.) 2001 QC, 4.7L, KENNE BELL SC'ed, 5spd.
3.55 LSD, Bored & polished TB, 10w-30 MOBIL 1, GIBSON 3" Single <A
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