LS6 intake manifold cracking
Thread Starter
Joined: Oct 2010
Posts: 589
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From: Kansas City, MO
LS6 intake manifold cracking I put my ls6 intake manifold on yesterday and torqued it to spec and went to a fbody meet last night. When i got home i popped the hood and looked around to see that the intake is cracking where the bolts go in to hold it down. Anyone ever have this happen to them? I can see where atleast 5 are cracked.
happened to the ls6 intake i bought, wel i bought mine like that, but got it cheap...ususally happens when theyre overtightened. its only plastic, dosent take much to do it in!
i cut the bad bolt bosses out, and got some aluminum pipe, cut the same length and used that in its place to clamp the manifold down.
i cut the bad bolt bosses out, and got some aluminum pipe, cut the same length and used that in its place to clamp the manifold down.
Thread Starter
Joined: Oct 2010
Posts: 589
Likes: 0
From: Kansas City, MO
Thread Starter
Joined: Oct 2010
Posts: 589
Likes: 0
From: Kansas City, MO
happened to the ls6 intake i bought, wel i bought mine like that, but got it cheap...ususally happens when theyre overtightened. its only plastic, dosent take much to do it in!
i cut the bad bolt bosses out, and got some aluminum pipe, cut the same length and used that in its place to clamp the manifold down.
i cut the bad bolt bosses out, and got some aluminum pipe, cut the same length and used that in its place to clamp the manifold down.
when i seen it, figured i'd have to buy another one. Trending Topics
did you remove the coolant tubes being a 99(in your sig) if not then you need to address this area also the tabs that hold down the knock sensors could also be an issue.
Can't see cracking those areas buy over torquing maybe one but not 5.
Good luck
Can't see cracking those areas buy over torquing maybe one but not 5.
Good luck
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Are the ferrules still in each of the bolt holes? Without them, the full torque will go into the plastic. This or what Sunset said. You need to grind clearance slots into the base of the LS-6 manifold to make it fit with the early 4-corner steam tube setup.
Thread Starter
Joined: Oct 2010
Posts: 589
Likes: 0
From: Kansas City, MO
ls6 intake on it. I think the tq wrench i used was junk and they got over tightened. I ended up buying another ls6 and im going to swap them. Hopefully the old one can be fixed. Ill try to snap some pics in the next couple days.
Thread Starter
Joined: Oct 2010
Posts: 589
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From: Kansas City, MO
I finally got the intake off and snapped a few pics of the cracks. Can it be fixed like the intake in Post #7? Other then what seen in the pics, the intake is perfect.
I just went out and looked at my spare manifold. Do you see where there are recessed cavities in the top of the bolt bosses? There are supposed to be some thick, light gray fiber washers in there that set flush with the top of the boss so the plastic edge won't get deformed or broken, as yours have. As far as fixing them, you might be able to fab some machined aluminum stepped pieces (would look like a bored out rim-fire cartridge) that would press/glue into your broken bosses...
Thread Starter
Joined: Oct 2010
Posts: 589
Likes: 0
From: Kansas City, MO
I just went out and looked at my spare manifold. Do you see where there are recessed cavities in the top of the bolt bosses? There are supposed to be some thick, light gray fiber washers in there that set flush with the top of the boss so the plastic edge won't get deformed or broken, as yours have. As far as fixing them, you might be able to fab some machined aluminum stepped pieces (would look like a bored out rim-fire cartridge) that would press/glue into your broken bosses...
I'd fix it, but I have the stuff to do it. You'll need to be able to or find someone who is. This is what your "fix" will look like from the side view. Scale to suit, add some epoxy, and press into the broken bolt towers...
