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My new 331 has finally gotten sick

  • Thread starter Thread starter Obsol3te
  • Start date Start date Aug 28, 2005
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Obsol3te

Member
Jun 29, 2005
106
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Aug 28, 2005
#1
  • Aug 28, 2005
  • #1
Well ran flawlessly except for an exhaust leak up by the headers that wouldnt go away even after a new gasket swap.
Guessing it's the headers, but here's the question:

Car is missing for no reason at all, and the thing is.
Not all the time either!
It'll run flawlessly, normally and how it just does and was day to day.
But then it'll start "missing"
You give it a little gas to help you cruise and it's backfiring. Doesn't really want to move anywhere.
But if you give it more gas, it'll "miss" more and get up to speed.
But I don't really want to do that.

Then it'll go back to normal after a few mins.

It doesn't do it at idle(unless it's very very very faint)

Everything in the engine bay is basically a year old or less, besides the pullies and wiring.

Got a complete MSD Ignition, last year
6al box, Billet dist, 8.5mm wires.
Running autolite copper 24's(just replaced)
Plug Wires don't look that bad, I do have a split boot on the 8th cylinder.
Very bottom of the plug and not too big at all, so don't think that could effect it.

And like I said, car was running fine.
Matter of fact awesome until a couple days ago.

Any suggestions?
 

powertrax91

Founding Member
Mar 13, 2002
598
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17
New York
Aug 28, 2005
#2
  • Aug 28, 2005
  • #2
i had most of the symptoms you described on both of my cars and both time it turned out to be dirty fuel filters... start with the little stuff first....change the fuel filter
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
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129
New York
Aug 28, 2005
#3
  • Aug 28, 2005
  • #3
What heads are you running? Check for codes? A wideband would possibly help nail down the issue. With out my wideband and my PMS, my car would be junk!
 

ZetecF1

New Member
Aug 8, 2001
25
0
0
MN
Aug 28, 2005
#4
  • Aug 28, 2005
  • #4
Make sure your Negative battery cable is properly grounded to your engine.

When I installed a new engine I had the same symptoms and that's what it ended up being.
 

Obsol3te

Member
Jun 29, 2005
106
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17
Aug 28, 2005
#5
  • Aug 28, 2005
  • #5
powertrax91 said:
i had most of the symptoms you described on both of my cars and both time it turned out to be dirty fuel filters... start with the little stuff first....change the fuel filter
Click to expand...

Replaced last year, didn't do too many miles on it.
But I'll pickup another.

Grn92LX said:
What heads are you running? Check for codes? A wideband would possibly help nail down the issue. With out my wideband and my PMS, my car would be junk!
Click to expand...

AFR 185's, Not pulling any codes.
And don't have the cash for a wideband, but was tuned via dyno a couple months ago.
Havnt done anything since.
ZetecF1 said:
Make sure your Negative battery cable is properly grounded to your engine.

When I installed a new engine I had the same symptoms and that's what it ended up being.
Click to expand...

Now here's what it could be.
Sanded down where I have it ground in the back(battery moved to trunk, grounded to floor...)
Drove around the neighborhood, was fine.
Drove up the street and got on it a couple times.
Perfect.
Turned around to head back home
Does it for a min or two.
Then stops and I pull into my driveway.
Going to pickup some 00 Cable and run it straight to the block.
I have aluminum heads, so where would be a good place to ground?
Also will try a new Fuel Filter.
But AutoZone is my only option
and it'll probably be like Valucraft or something.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Aug 28, 2005
#6
  • Aug 28, 2005
  • #6
Ok, well you have the WRONG spark plugs in first of all. You need autolite 3924's, NOT autolite 24's. Thats one problem fixed

When you move the battery to the trunk you have to go with good wiring and big gauge.
 
U

universalstang

New Member
Aug 26, 2005
3
0
0
Aug 28, 2005
#7
  • Aug 28, 2005
  • #7
I got a question, sorry to kinda high jack your thread.

I have autolite 25's thats what napa recommended.

I have high compression and 185's also. Also XE 282 HR cam.

would 24's work better, cause my car sometimes back fires out of the carb, then runs fine?

Thanks...
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Aug 28, 2005
#8
  • Aug 28, 2005
  • #8
Universal- you NEED autolite 3924's for your car, NOT autolite 25's. Don't listen to what the idiots behind the desk say.
 

Obsol3te

Member
Jun 29, 2005
106
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17
Aug 28, 2005
#9
  • Aug 28, 2005
  • #9
Grn92LX said:
Universal- you NEED autolite 3924's for your car, NOT autolite 25's. Don't listen to what the idiots behind the desk say.
Click to expand...

Are the 3924's Copper?
I need 1 step colder copper plug.
Thought the 24's were That.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Aug 28, 2005
#10
  • Aug 28, 2005
  • #10
The 3924's are a longer reach plug which is what you need with alum heads. The 24's you have now aren't all the way in the chamber enough. 3924's are what you need for that n/a combo. I run them in my TW heads and have been for the past 4+ years.
 
J

Jeff7477

Founding Member
Jul 2, 2001
176
0
0
Lincoln, Nebraska USA
Aug 28, 2005
#11
  • Aug 28, 2005
  • #11
wtf is a 3924?

I always use 25's
 
U

universalstang

New Member
Aug 26, 2005
3
0
0
Aug 28, 2005
#12
  • Aug 28, 2005
  • #12
Im gonna switch to the 3924 tomorrow, I'll start the car and tell you guys how it runs. Might fix my over heating problem.

Thanks Green
 

Obsol3te

Member
Jun 29, 2005
106
0
17
Aug 28, 2005
#13
  • Aug 28, 2005
  • #13
I do run a small shot of the n2o
and would like the safety of a step colder plug.
Are those, 3924's colder and copper?
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Aug 28, 2005
#14
  • Aug 28, 2005
  • #14
Obsol3te said:
I do run a small shot of the n2o
and would like the safety of a step colder plug.
Are those, 3924's colder and copper?
Click to expand...

Then use autolite 3923's if you spray the car. How much of a shot? Gap them smaller too.
 

Obsol3te

Member
Jun 29, 2005
106
0
17
Aug 28, 2005
#15
  • Aug 28, 2005
  • #15
Nothing much, a wimpy 75 shot.
Might as well list my combo:

r331 AFR 185's 8.5:1 comp
75 dry nitrous, edelbrock performer rpm upper/lower
Egh, screwit if interested, www.cardomain.com/id/obsol3te
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Aug 28, 2005
#16
  • Aug 28, 2005
  • #16
Why such low compression? The 3924's may work, but i'm not sure exactly. Its only a small 75 shot.
 

Obsol3te

Member
Jun 29, 2005
106
0
17
Aug 28, 2005
#17
  • Aug 28, 2005
  • #17
The low compression is for future plans, Single Turbo + Decent amount of boost.

And I know it's only a small 75 shot.
Hence me saying I want the safety of a colder plug.
Don't really want to melt one because of having the normal heat range.
 
3

331 stang91

Member
Oct 16, 2004
261
0
16
wisconsin
Aug 28, 2005
#18
  • Aug 28, 2005
  • #18
After I swaped my motor I had the same problem. It turned out to be my fuel pump. Put in a new 190 and it ran fine. good luck
 

jaymac

New Member
Feb 18, 2004
995
0
0
Northern Mass
Aug 30, 2005
#19
  • Aug 30, 2005
  • #19
First of all, if you had made the damn sig like your sig says you're "doing", you could've saved yourself alot of extra typing and gotten more efficient repiles more quickly.
But nobody knew your CR, your 75 shot, you tune, etc.
It's not just for show, brotha, it's to help us to help you!!!

Anyhow, did Menard's call you back about the bumper?
 

jaymac

New Member
Feb 18, 2004
995
0
0
Northern Mass
Aug 30, 2005
#20
  • Aug 30, 2005
  • #20
331 stang91 said:
After I swaped my motor I had the same problem. It turned out to be my fuel pump. Put in a new 190 and it ran fine. good luck
Click to expand...

Oh, and he's already got a 255 lph pump, but YOU WOULDN"T KNOW THAT BECAUSE HE CHOOSES NOT TO HELP US BY POSTING A SIG SO WE CAN KNOW WHAT WE'RE ACTUALLY WORKING WITH!!!!!!!!!!!!!!
 
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