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Getting pissed ...only 8-13 in vac at idle

  • Thread starter Thread starter lx2c6
  • Start date Start date Oct 3, 2005
L

lx2c6

New Member
Apr 6, 2005
37
0
0
Oct 3, 2005
#1
  • Oct 3, 2005
  • #1
quick details on my situation ...i just built a 302 , i got the short block from d&d motorsports arp bolts, probe forged pistons , pro topline heads ,scorpion 1.6rr stud mount custom grind cam 544/544, canton oil pan , gt-40 upper and a explorer lower , accufab 70mm TB , 73mm maf , adj fuel psi reg set at 40 psi , 190lph fuel pump, ok ever since the motor first started the motor sounds like a diesel for one so i fig it needs the rockers adj but nope i adj 3 diff times and the last time with the car running so i know they are right , my other problem is that i have only 8-13vac and a flucuating needle so im guessing my valvetrain to be the issue i have brand new lifters ( yes i soaked them ) so i did a compression test and my compression was just about even except #7 was 175 all other right around 190 so i figured if my valve was staying open my compression would not be that great i know i need to do a leak down test on all cyl but wouldnt my compression numbers be down if my valve was sticking open ? i will have more info on the situation later any help i will be greatefull thanks
 

RacEoHolic330

I like to dress like a pretty girl
15 Year Member
Mar 4, 2003
4,014
1,698
203
Allentown, PA
Oct 3, 2005
#2
  • Oct 3, 2005
  • #2
It sounds like you have a vac leak somewhere. You should check around the upper and lower intake gaskets. I had that issue with my car at first. Turns out I blew out one of those cork lower intake gaskets. I have an anderson b-31 cam (.544/.544) and pull around 15-16 at idle (~800rpm) when the car is at operation temp.
 

NosPony

New Member
Apr 2, 2004
278
0
0
Canton, Il
Oct 3, 2005
#3
  • Oct 3, 2005
  • #3
Sounds like a vacuum leak to me. I am running a x-303 cam in my coupe and I only pull around 13 on the vacuum gauge.
 

88_GT_5_oh

Sportin' a turbo 5.0 in Canadistan
Jul 4, 2004
1
0
1
WPG/MB/CA
Oct 3, 2005
#4
  • Oct 3, 2005
  • #4
re check your rockers (yes again) and let it run for a bit, they will make noise at first but it should go away. if not start spraying carb cleaner around your vac lines an see is the idle jumps up.


also with my trickflow stage 1 cam i am only pulling about 12 vac at idle when its all warmed up
 
D

Daggar

New Member
Jul 19, 2004
3,902
5
0
Oct 3, 2005
#5
  • Oct 3, 2005
  • #5
544/544 What's that? If that's your intake and exhaust lift then it doesn't have much to do with your vac. What's the overlap?
 
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