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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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backfire in intake

  • Thread starter Thread starter greengoblin95
  • Start date Start date Oct 27, 2009
G

greengoblin95

Member
Sep 29, 2009
92
0
6
Oct 27, 2009
#1
  • Oct 27, 2009
  • #1
I have checked for vacuum leaks which i can honestly say that i dont have any, my timing is set a 16 degrees since i dont have my blower belt on and my fuel pressure is at 36 at idle. i have my trickflow stage 1 cam advanced 2 degrees and that is the only thing that i can think of at this point that would cause this problem. has anyone else had a problem with advancing the cam timing?
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 27, 2009
#2
  • Oct 27, 2009
  • #2
A popping in the intake is typically either incorrect cam timing or a very lean condition.

Wes
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
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Oct 27, 2009
#3
  • Oct 27, 2009
  • #3
Is it a consistent popping? You're not suposed to run the engine with the blower on, and not the belt. See what happens when you put the blower belt on.

Kurt
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 28, 2009
#4
  • Oct 28, 2009
  • #4
revhead347 said:
You're not suposed to run the engine with the blower on, and not the belt. See what happens when you put the blower belt on.
Click to expand...

What's the reason behind this?

Wes
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,301
1,643
214
Acworth, GA
Oct 28, 2009
#5
  • Oct 28, 2009
  • #5
It restricts the flow into the engine, and can mess up air meter readings depending on where your meter is located. I've seen a few people try this with crappy results.

Kurt
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 29, 2009
#6
  • Oct 29, 2009
  • #6
The MAF should not be affected with the blower off. Even if your airflow is a bit choked there will be no harm to the engine if your tune is setup properly (which will not care if the blower is turning or not).

While it's not a great permanent solution don't be afraid to pull off the belt so you can hear the car running to check for exhaust leaks, vacuum leaks. I personally do this quite often for blower cars that are new builds.

Wes
 
G

greengoblin95

Member
Sep 29, 2009
92
0
6
Oct 29, 2009
#7
  • Oct 29, 2009
  • #7
i have sprayed my engine all over for vacuum leaks and nothing has been found. from carb cleaner to starting fluid. ill just reset my cam timing to 0* to to make sure its not too advanced. i know that the cam has an advance already ground into it.
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 29, 2009
#8
  • Oct 29, 2009
  • #8
As a quick test you can dial in about 10lb of fuel pressure with your adjustable regulator and see if the popping lessens.

Wes
 
G

greengoblin95

Member
Sep 29, 2009
92
0
6
Oct 29, 2009
#9
  • Oct 29, 2009
  • #9
Stanger007 said:
As a quick test you can dial in about 10lb of fuel pressure with your adjustable regulator and see if the popping lessens.

Wes
Click to expand...

what would leaning it out prove? to see if the motor will still run with fuel only?
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 29, 2009
#10
  • Oct 29, 2009
  • #10
ADD another 10lb to get you to 50psi. That will richen it up and let you know if the popping is a lean condition.

Wes
 
G

greengoblin95

Member
Sep 29, 2009
92
0
6
Oct 29, 2009
#11
  • Oct 29, 2009
  • #11
ok lol, at first i thought you were talking about taking 10 away. ill have to get some longer screws for my adj. fpr. the base is thicker and the stock screws are not long enough and i was having an leak. ill do that this weekend also as i pull the timing cover off
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,301
1,643
214
Acworth, GA
Oct 29, 2009
#12
  • Oct 29, 2009
  • #12
I say put the belt on the blower and see if it goes away.

Kurt
 
G

greengoblin95

Member
Sep 29, 2009
92
0
6
Oct 30, 2009
#13
  • Oct 30, 2009
  • #13
well, before i was going to take the timing cover off, i just went ahead and put the belt on, connected the battery after a week and cranked it up. its a beast. i guess it was starving from tight tolerances in the blower. i asked vortech about this 3 weeks ago about possibly starving the motor without the belt and they said it wouldnt effect it. yea right, its a monster and sounds great, got some adjustments to make still and now with the break in. i do appreciate all the help guys.
 
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