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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Post your vaccum numbers. Do I have a vac leak?

  • Thread starter Thread starter 98BLKGT
  • Start date Start date Jun 1, 2007

98BLKGT

Founding Member
Dec 23, 2001
322
1
0
Chicago area
Jun 1, 2007
#1
  • Jun 1, 2007
  • #1
How much vaccum do you get at idle?
What is your RPM at idle?


I get 10" at idle. Do I have a vac leak? I have an F cam so my vac numbers may be lower I think.
I'm asking because I have a bit of hesitation at 2000 rpm and the idle surges if the weather is below ~70 degrees.
 

AnthonyR23

Member
Sep 8, 2006
661
0
16
Ontario
Jun 1, 2007
#2
  • Jun 1, 2007
  • #2
I'm getting 20
 

AnthonyR23

Member
Sep 8, 2006
661
0
16
Ontario
Jun 1, 2007
#3
  • Jun 1, 2007
  • #3
do you still have the stock vacuum lines.. If so... I would suggest picking up a kit for about 24.99 from mustangs unlimited ... comes in different colors.... and gives you more than enough to do everything under the hood.. after replacing the lines see if your vacuum goes up.... if not I think there is a electric vacuum pump you can get that would definetely help.. I think I have heard of other people who get 10 so that could be ok... a bit of a pricey option but there are electric vacuum pumps... that turn on when vacuum is below 15 and turns off when it reaches 25... just a option but about a 300 dollar one.
 
R

RioRed4v

New Member
Aug 1, 2003
24
0
0
Las Vegas
Jun 1, 2007
#4
  • Jun 1, 2007
  • #4
i have 13.5 with my custom cam, which is what the cam card says it should be.


i would check to see if you can find a cam card somewhere online for the F cam to see what the vacuum #'s should be with that cam.
 

millhouse

Founding Member
May 14, 2002
1,985
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46
Simpsonville, SC
Jun 1, 2007
#5
  • Jun 1, 2007
  • #5
What's your idle rpm?

Mine pulls ~ 12" at around 800-850 rpm.
 

98BLKGT

Founding Member
Dec 23, 2001
322
1
0
Chicago area
Jun 1, 2007
#6
  • Jun 1, 2007
  • #6
~650-750 rpm
@1000 rpm I get about 12"
 
J

jballa

Member
May 17, 2007
32
0
6
Jun 1, 2007
#7
  • Jun 1, 2007
  • #7
Hoover model # 1902


Suck a bowling ball up :Track:
 
S

Sicarius428

Active Member
Jan 6, 2004
2,085
5
49
Jun 1, 2007
#8
  • Jun 1, 2007
  • #8
13-14 with the stuff in my sig.
Kevin
 

Blown83GT

New Member
Sep 20, 2004
35
0
0
South Jersey
Jun 2, 2007
#9
  • Jun 2, 2007
  • #9
E-cam 13" vac at 750 idle
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Jun 2, 2007
#10
  • Jun 2, 2007
  • #10
AnthonyR23 said:
... a bit of a pricey option but there are electric vacuum pumps... that turn on when vacuum is below 15 and turns off when it reaches 25... just a option but about a 300 dollar one.
Click to expand...
PLEASE provide a link to such a system...




Idle vac depends on countless factors...
even ignition timing will have an impact...


10" at idle is kinda low, but you are running an alphabet cam, so who knows...

I probably wasn't much help,
jason
 

98BLKGT

Founding Member
Dec 23, 2001
322
1
0
Chicago area
Jun 2, 2007
#11
  • Jun 2, 2007
  • #11
Ok so I might redo all my vaccum lines since I don't know what the previous owner did. I need some of your guys help with this.
I don't have the smog pump hooked up, no egr hooked up, no A/C hooked up, no cruise control on the car.
Wouldn't this mean that the only vaccum lines I need is the PCV, fuel pressure regulator, and brake booster? Anything else I NEED vaccum lines running to?
 

dls322

Member
Apr 4, 2005
149
0
16
Mt. Penn, PA
Jul 11, 2007
#12
  • Jul 11, 2007
  • #12
You need a line to your MAP sensor too, correct?
 
S

Sevan

Founding Member
Dec 4, 2001
558
0
16
IL
Jul 11, 2007
#13
  • Jul 11, 2007
  • #13
how do u check for vac. numbers? i just dropped a 347 with ford racing x-cam with 1.7's. idle is supposed to be fair, but at idle sometimes the rpm tach is all over the place and wants to shut off. sometimes the rpm shoots up to 1500 then drops then back up again. i dont have a/c, smog, air canister i think thats what its called. any help would be appreciated....thanks
 

98BLKGT

Founding Member
Dec 23, 2001
322
1
0
Chicago area
Jul 11, 2007
#14
  • Jul 11, 2007
  • #14
Vaccum/Pressure tester at summit/autozone or a little gauge

 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Jul 12, 2007
#15
  • Jul 12, 2007
  • #15
dls322 said:
You need a line to your MAP sensor too, correct?
Click to expand...

If a car is SD, yes.
If it's MAF, no.
 
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