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Wet spark plugs....

  • Thread starter Thread starter 65fastbackresto
  • Start date Start date Sep 25, 2007

65fastbackresto

Active Member
Apr 13, 2007
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Sep 25, 2007
#1
  • Sep 25, 2007
  • #1
ok my 302 has been running for about 15 minutes (brand new build) and is not burning all the gas in the cylinders (heavy gas smell at exhaust and wet spark plugs). It is backfiring and I cant seem to get it to stop, I suspect timing is off but cant seem to get it right. Can anyone give me the firing order and maybe some tips to trouble shoot this?

Right now its firing order is set at 13726548, I just found an old post that says it should be 15426378......
Would it still run but kinda rough it its wired wrong?
 

SoCalCruising

Founding Member
Jul 25, 2000
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SoCal
Sep 25, 2007
#2
  • Sep 25, 2007
  • #2
Your firing order is dependent on how your cam is ground. If it is ground as a 351W or 5.0 (which uses the 351W order), then the 13726548 is correct. The other order is the 289/early 302 order. If you have a cam card, it should have the firing order. If you don't have the cam card, call your engine builder and ask if is 289 or 351W firing order.

Do you know what your fuel pressure is? What kind of pump are you running? Do you have a fuel pressure regulator plumbed into your fuel line between the pump and carb?
 

Fast63

New Member
Sep 20, 2007
717
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0
Sep 25, 2007
#3
  • Sep 25, 2007
  • #3
If you're wired in the wrong firing order then it absolutely will run as you described. My guess is you have a flat tappet 302 cam, which will be the older 15426378 firing order. Even if you dont know, swap the order to that and see how it runs. All you have to do is switch the wires at the cap!
 

65fastbackresto

Active Member
Apr 13, 2007
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Sep 26, 2007
#4
  • Sep 26, 2007
  • #4
It was the firing order

this thing is gonna be sweat, it fired right up, after I got idled right and stuff it lopes just a little, sounds awesome with the currently open headers. I saw the local cop last night, asked him if it`d be ok to run around town with open headers for a few days, he said no problem. This is gonna be fun.....I think I can get away with it till Monday or so.

And SoCal, its a stock pump, dont know the pressure, and I dont have a regulator. Everything seem sfine now though, except it wont go in reverse for some reason.
 

oldfordguy

New Member
Sep 22, 2007
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Da windy city
Sep 26, 2007
#5
  • Sep 26, 2007
  • #5
lucky on both counts...car is running and you got a cop to look the other way!
 

fasttback

New Member
Apr 16, 2005
471
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Northern CA
Sep 27, 2007
#6
  • Sep 27, 2007
  • #6
65fastbackresto said:
I saw the local cop last night, asked him if it`d be ok to run around town with open headers for a few days, he said no problem. QUOTE]

Wow! I wish I could do that, but unfortunately my local anal police force would think otherwise. I get unfriendly looks as it is now.

Try to pull next to a Harley with your open headers so they can hear what they dish out.
Click to expand...
 

65fastbackresto

Active Member
Apr 13, 2007
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Sep 27, 2007
#7
  • Sep 27, 2007
  • #7
Yea this really sucks

permission to terrorize the general public, and the tranny is broke. I`ll have to wait a few more days
 

oldfordguy

New Member
Sep 22, 2007
11
0
0
Da windy city
Sep 28, 2007
#8
  • Sep 28, 2007
  • #8

now that is really ironic and wrong. tell ya what I'll risk it ,uncork and burn some rubber in your honor up here...
 
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