Intake Manifold Studs
#1
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I was finally bitten. When pulling my intake manifold off one nut just fell off with the half stud in it. What are you track people doing for intake manifold studs? They seem to fail left and right for the auto-x people, the csp car ended up replacing an entire set worth this season IIRC. They're m8x1.25 I need to pull a good one to get the length. Do we just replace with OEM as the break or have an upgraded option? Mcmaster doesnt have 10.9 studs, but they do have 4140 for pressure bolted connections in high pressure systems. Minimum tensile strength of 124,000 psi and max hardness of Rockwell C35, which is in between class 8.8 and class 10.9 for both strength and hardness.
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tap the bolts out for a larger size- best option, not easy to do properly in the car.
use higher grade bolts (not as ductile though in most cases, so it likely wont help)
use the intake manifold bracket - if your a weight weenie for the 1/2 lb that the brace isare, drill some holes in it in the middle of the web, leave the outside of the web for strength.
use higher grade bolts (not as ductile though in most cases, so it likely wont help)
use the intake manifold bracket - if your a weight weenie for the 1/2 lb that the brace isare, drill some holes in it in the middle of the web, leave the outside of the web for strength.
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Then I'd vote for bracing. Just like on the turbo/exhaust side of things. I actually had my turbo come off the manifold recently because of a broken exhaust hanger in the rear.
Sucks to add weight but it might be necessary. Also you can probably fab up something lighter and just as good than the factory brace with a swaged rod or turnbuckle.
Sucks to add weight but it might be necessary. Also you can probably fab up something lighter and just as good than the factory brace with a swaged rod or turnbuckle.
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But the turn buckle wont work, too many axis of movement, it just becomes a point for the manifold to rotate around. It needs a solid connection if its going to have a brace.
I took a look back at one of the old engineering texts, my failure may potentially be an under torqued fastener, or just a lack of yield strength in the fastener. I'm going to find some class 10.9 studs, and actually use a torque wrench. And probably re-calculate the actual torque spec to be 60% of yield for the new studs.
I took a look back at one of the old engineering texts, my failure may potentially be an under torqued fastener, or just a lack of yield strength in the fastener. I'm going to find some class 10.9 studs, and actually use a torque wrench. And probably re-calculate the actual torque spec to be 60% of yield for the new studs.
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Even cheaper? A piece of square or round tubing could be abused in pretty quick fashion for this and probably still lighter than the abused factory one.
It looks like Dorman has some M8x1.25 10.9 studs.
Dorman Products - Double-Ended Studs Class 10.9
Last edited by mcfandango; 12-03-2013 at 02:47 PM.