Spark Blowout

OrangeMustangGt

Founding Member

Mar 7, 2002

1,976

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36

Cape Cod, MA

Feb 8, 2007

#1

• Feb 8, 2007

• #1

I just put new plugs in my car while i had my turbos out, and i figured since i have a ignition box and coil now, i would gap them at what they came out of the box with (Autolight 103's)

Now, at 5psi of boost, around 4-5,000 rpms the car is getting a miss or hesitation under full throttle....

It feels like spark blowout......BUT is there a good way to make sure?


my car is REALLY hard to change sparkplugs......i have to go underneath, etc!

 

GT_green_GT

New Member

Dec 31, 2005

118

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0

Feb 8, 2007

#2

• Feb 8, 2007

• #2

well....before going to all the trouble to pull the plugs out. Make sure all the cables are on and tight.

 

SQUEEZE&STROKE

New Member

Jun 24, 2005

0

0

0

SOUTHERN CA

Feb 8, 2007

#3

• Feb 8, 2007

• #3

Its the plugs...My lightning did the same thing. Re gap them...I gapped mine at 38

 

blksn955.o

Founding Member

Mar 15, 2002

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66

st.louis mo 314

Feb 8, 2007

#4

• Feb 8, 2007

• #4

Even with a ign. box any kind of boost will blow out the plug if at its stock gap I would think...it is like .055-.060 or whatever stock right. I would just run them at .035-.038 its not going to hurt you any to have a tighter gap, maybe alittle less life out of the plug.

 

OrangeMustangGt

Founding Member

Mar 7, 2002

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Cape Cod, MA

Feb 8, 2007

#5

• Feb 8, 2007

• #5

yeah.....i know this deep down inside, and i wish i had gapped to .035 but......you have NO idea how much i dont want to change my plugs again lol.....lits like a LT-1 camaro!

Anyhow, ill just have to break down and change them....if i remember correctly the gap on the plugs out of the box was .040 or .045.

 

rio95

Member

Nov 18, 2003

829

1

17

Grand Rapids, MI

Feb 9, 2007

#6

• Feb 9, 2007

• #6

GreenMustangGt said:

yeah.....i know this deep down inside, and i wish i had gapped to .035 but......you have NO idea how much i dont want to change my plugs again lol.....lits like a LT-1 camaro!

Anyhow, ill just have to break down and change them....if i remember correctly the gap on the plugs out of the box was .040 or .045.

Click to expand...

I'm suprised you didn't know that 0.045" is crazy. Mine are at 0.029".

They're not even all the same out of the box, which is even worse. Stock is 0.056"

 

SQUEEZE&STROKE

New Member

Jun 24, 2005

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SOUTHERN CA

Feb 9, 2007

#7

• Feb 9, 2007

• #7

GreenMustangGt said:

yeah.......you have NO idea how much i dont want to change my plugs again lol.....lits like a LT-1 camaro!

Click to expand...

Tell me about it...have you ever changed plugs on a lightning?

To put it in perspective...I had the entire blower, tb, intake plenum, etc off 6 times in 4 days looking for that stupid problem.

 

rio95

Member

Nov 18, 2003

829

1

17

Grand Rapids, MI

Feb 9, 2007

#8

• Feb 9, 2007

• #8

Does this miss feel the same in every gear, or can you not notice it in 1st and 2nd?

 

OrangeMustangGt

Founding Member

Mar 7, 2002

1,976

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Cape Cod, MA

Feb 9, 2007

#9

• Feb 9, 2007

• #9

i dont notice it as much in 1st and 2nd....more noticable when im doing londer runs.


I used to have a .035 gap but if figured i would open it up due to the box that i got......guess i learnt i cant.

Sucks......Oh whell, thats what im doing this weekend!

 

Blackened302

Active Member

Jul 21, 2005

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36

South TX

Feb 9, 2007

#10

• Feb 9, 2007

• #10

GreenMustangGt said:

my car is REALLY hard to change sparkplugs......i have to go underneath, etc!

Click to expand...

is that because of the gt40p non-spec headers or because you have very little room w/ your tt setup?

 

gmkillr

Founding Member

Jul 13, 2002

606

1

18

Feb 9, 2007

#11

• Feb 9, 2007

• #11

W/ 11lbs. of boost I was blowing my Denso's out w/ a .035" gap and a crane ignition box & coil, gapped them down to .028" and there fine.

 

OrangeMustangGt

Founding Member

Mar 7, 2002

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Cape Cod, MA

Feb 10, 2007

#12

• Feb 10, 2007

• #12

its basically because of the tt setup, you have the headers, then a downpipe on each side....makes it tight......ok man thanks, ill think about maby gapping a bit lower.