97camaro383

iTrader: (31)

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.

JaYZeig

iTrader: (11)

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.

BudRacing

iTrader: (3)

How tight did you torque it? It only calls for XX inch/lbs which translates to about 7 ft/lbs which is only "snugged" up.

97camaro383

iTrader: (31)

I did 8ft lbs or thats what the tq wrench said but i have a feeling its a POS

97camaro383

iTrader: (31)

Do you have any pics of the work you had to do to it? I thought i was f*cked when i seen it, figured i'd have to buy another one.

The_Bishop

iTrader: (10)

Buy an inch-pound torque wrench! You cannot dial a foot-pound wrench down far enough for this to work correctly.

JaYZeig

iTrader: (11)

sorry for the late responce!
heres how i fixed mine

Sunset01TA

iTrader: (7)

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

S10xGN

iTrader: (11)

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.

97camaro383

iTrader: (31)

Yea it has the ls6 coolant tube on it already, previous owner used to have a
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.

97camaro383

iTrader: (31)

My new intake has metal washers or something on it already, the old one was just plastic there. Would that cause the cracking?

new intake

S10xGN

iTrader: (11)

You can see the brass sleeve on the bolt hole to the far left, all of the holes have them, but the corners are more easily visible:

97camaro383

iTrader: (31)

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.

S10xGN

iTrader: (11)

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...

97camaro383

iTrader: (31)

The new intake i got has the light gray pieces that make it flush, think thats the reason it cracked then?

S10xGN

iTrader: (11)

Yes, you're putting the full torque of the bolts on the thin lip of the manifold instead of spreading it over the full face.

97camaro383

iTrader: (31)

Think itd sell as is or should i try to cut and get aluminum pieces to fix it?


I appreciate all the replys.

S10xGN

iTrader: (11)

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...