[FC] Vacuum advance issue -

[Andrew Sego]

The other possiblility is that the idle speed is set too high.  In fact if the engine is at slow idle (chokes off) thedistributor should not see vaccum advance until the engine is revved.  Try dailing back the idle speed to 550-600rpm



________________________________
From: Jeff Brylow <jeffbrylow at gmail.com>
To: corvanatics at corvair.org 
Sent: Wednesday, August 29, 2012 1:11 PM
Subject: [FC] Vacuum advance issue -

Folks - First issue - I've been attempting to dial in the engine in my '64
Greenbrier for some time now and have an issue that has me stumped. Quite
simply the vacuum advance seems to be performing too well! I'm experiencing
hesitation on take off and I believe excess spark advance may be the issue.

With the vacuum line disconnected, as is called for during the normal
timing procedure, I can time the engine, vehicle in drive, right at 13
btdc.  Then when I hook up the vacuum advance line from the carb, I
immediately get at least 10 degrees of advance at idle. I've tried  three
different advance units all with the same results.

Some facts to help with any offers of help  -

Engine  code- "ZB"  '61 - '62  80 hp

carb codes - left bank 7020101 / right bank 7019110

distributor - # 1110272 / vacuum advance #951

head # 3786588.

Second issue (related to first issue?)  - I'm only seeing 5-7 in. hg at the
carbs with my vaccum gauge and the truck actually seems to run quite well
here. This is with the curb idle set at 1-1/2 turns in per factory setting.
Many sources state we should see 14-18 in hg.
.
Third  issue (question) - I ran a compression test recently - results  as
follows - #1 - 140# , #2- 145# , #3 - 142# , #4 - 141# , #5 - 157# , #6 -
140#. These numbers seem a bit high to me. Are these numbers normal for a
80 hp. engine?

Thanks,

Jeff B. - Wisconsin

'64 Monza sedan

'64 Greenbrier

'62 Greenbrier Deluxe (running parts car)
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