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RIP (12/27/60-7/18/15)
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767 Posts
Discussion Starter #1
Hi gang... I have an exhaust leak between my intake manifold and head on the passenger side. right where the crossover is. my mechanic had me put on a stethoscope ......when I ran it over the leak it sounded like a 747 taking off. im so sick of that stupid crossover........
pretty sure this happened the last time I rebuilt the motor(felpro gaskets). but cant remember what I did to fix it. can I simply block the passage?
Is there a quickfix to this? guessing I need to do it right and remove the intake.but then what? :banghead:
thanks as always and always.
hoists a glass of Knob Creek to Uncle G and the gang!
happy 'olidays lads
Tk
 

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Premium Member
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662 Posts
Tk, you installed the wrong gasket. The cross over port on the right side of the intake manifold is bigger than the port at the head. I'm guessing you have the correct gasket in the set, so it is a matter of pulling the manifold back off and installing the correct gasket. This actually happens a lot. Matt
 

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58 Posts
Are the heads or Intake mismatched


Exhaust Crossover Port Matchings
With Head/ And Manifold/Use Gasket
1965-71---- 1965-71----- 1965-71
1965-71----- 1972-79----- 1972-79
1972-79----- 1972-79----- 1972-79
1972-79----- 1965-71----- 1965-71**

** Use thin sheet stainless steel as a block off plate.



Casting numbers with asterix didn't have numbers cast into intake.
 

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64-67 Expert
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8,561 Posts
TK, what Matt said. You installed the wrong gasket for your head/intake combo. You can, however, successfully rig it if you'd like, and it will work forever: loosen the intake bolts around the port, and slip in an 'eyebrow' cut from another intake gasket (can be a used gasket). Coat the 'eyebrow' piece with high temp silicone, slide it in, and tighten the intake bolts back up. These only leak on the top, and you can seal it this way. Ten minute fix. (The right way is to install the correct gasket.....but this fix will work for years)
 

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64-67 Expert
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8,561 Posts
Forgot to add: do NOT use a blockage plate on a street driven car. No performance benefit, and you'll have a cold blooded beast that will run rich with slow warm ups and lots of raw fuel to wash the rings and dilute the engine oil. Great for shortening engine life on a street car.
 

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RIP (12/27/60-7/18/15)
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767 Posts
Discussion Starter #6
Wow, that's a cool sounding idea guys thanks!. The Goat and I hav'nt been on the best of terms lately (lol)
About what dimensions would an 'eyebrow' be?
thanks as always and 'appy 'olidays!
TK
 

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64-67 Expert
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8,561 Posts
The eybrow is cut from another intake....the upper part of one of the ports. Self-explanatory! It just needs to fit into the area that you didn't seal because you used the short gasket.
 

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RIP (12/27/60-7/18/15)
Joined
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767 Posts
Discussion Starter #8
Guess I tossed the remnant of my gasket set :(, did find some blue gasket material. I ended up loosening all the intake bolts and with a big screwdriver tried prying up on the intake via the valley pan. And of course it didn't move at all.
Tightened everything back down and monkey tightened the 2 bolts at the crossover. repainted the area silver.,
Of course this wont work and I shall end up doing the job right,
bummer lol
happy holidays everyone!
Tk
 
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