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86 LX 5.0 Blues

  • Thread starter Thread starter tramplar
  • Start date Start date Jul 8, 2007
T

tramplar

New Member
Jul 8, 2007
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0
Jul 8, 2007
#1
  • Jul 8, 2007
  • #1
Alright guys here is a brain tease for you.

I have a 86 mustang LX with the 5.0. Tore off the heads, intake, took out cam. Redid the top end of the motor.

Edelbrock pedestal mount alum. head has 1.90 intake.
Performer Intake
Double roller timing chain
edelbrock roller cam .498 lift
Bottom end is stock bore with 331 stroker kit on it. No the car was bought like that. I dont know what was done with bottom end. (going with what i have been told by the previous owner) Guy stroked it using the stock pistons which are flat tops with no valve relief.

Before tear down on motor it ran very strong. Now I have everything back together fire it up, and there is a chatter from the top end. Its not a lifter sound, lifters werent noisy before tear down. Its a tin type sound, its hard to describe. Its not a rod bearing that has a distinct sound. Now before you say its valves touching the pistons, I talked to a edelbrock tech for almost a hour, he said the heads I have now will clear the stock flat tops. The way it sounds, when it idles and runs fine is valve to piston slap, but its not loud and engine has no problems turning over. Im at wits end, I checked all rockers, stock rockers for now till i cure this problem. I checked the timing, i redid the torque down sequence on the rockers. Even my friends who are musatng gurus were stumped as as what it really was. But now if you give it alittle gas, it bck fires and has no power. To me that would sound like a timing problem and no firing order is HO firing order i made sure it was right, am i right to think that, yet i put the gun on the motor and its dead at 10 btdc. Any other things i am over looking? If it is timing issue what is the ticking noise then? Solutions?
 
9

93lxdm78

New Member
Jun 19, 2007
71
0
0
Jul 8, 2007
#2
  • Jul 8, 2007
  • #2
Its probaly just an exhaust leak from the headers that will sound like rockers or like something is rattling in your motor sometimes, But I bet you have an exhaust leak.

I would go to auto zone and get a sound scope and listen to the motor with that to verify its not internal.

Mine makes the same sound just ordered some good header gaskets to fix that issue.

Hope this helps
 
T

tramplar

New Member
Jul 8, 2007
2
0
0
Jul 8, 2007
#3
  • Jul 8, 2007
  • #3
93lxdm78 said:
Its probaly just an exhaust leak from the headers that will sound like rockers or like something is rattling in your motor sometimes, But I bet you have an exhaust leak.

I would go to auto zone and get a sound scope and listen to the motor with that to verify its not internal.

Mine makes the same sound just ordered some good header gaskets to fix that issue.

Hope this helps
Click to expand...

My smog tube on the back of my heads is leaking on both sides, I know my BBK headers arent leaking I work at autozone (lol) Im a manager there, I got the percy header gaskets (soft aluminum). Those two leaking smog outlets on the back of the head make that racket like that?
Maybe i should plug them up and see if it stil makes the noise.
 
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