Mounting bolts for ported intake

Strokersace

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What size bolts do I need for a ported intake. Similar to an RCD or Midwest stage 2?

I bought a used one off this forum and was told the mounting hardware was "coming separately". Well, you guessed it, never showed up!

The intake has all of the stands milled out.

Thank you.
 

footlong70

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Something I encourage you to do as with anyone is to double check the length of the manifold bolts as they fasten the manifold down. I learned the hard way when i installed a brand new stage 3 ported manifold from a highly reputable vendor. The manifold for starters was slightly warped, not a lot but if laid down on a flat surface, there was a 3/16-1/4" gap at the most extreme part. Secondly which is actually my point, the bolts that came with the kit bottomed out in the cyl head's threads just as it came into contact with the milled out pillars. So having thought I was torquing the manifold down, I was actually cutting new threads and flattening the bolt tip into the head. You'd think I'd notice but given the slight warp of the manifold, some tension was still on the manifold, nothing moved and all felt tight. I put everything back together and took for a drive to find out I was 15psi low on boost. Did a pressure test and sure enough the manifold was pissing air all around the head intake mating surface. Not happy obviously, I pulled everything apart to find it was too long of bolts, or they milled more out of the pillars than normal. I measured the bolt torqued/bottomed out into the head with no manifold, and the manifold pillar thickness w/ gasket, the pillars were just about the same thickness or thinner. Anyways I ended up adding 2 washers to every bolt, torqued it down, pressure tested and shes 100%. Its been good for the 2 years with periodic pressure tests.
So the point is just check it out when you install it, mine was more then likely one in a thousand as I've never heard anyone complain but who knows, even the big boys make mistakes with their products. Also not knocking the company as they have been good to me and have helped pave the way for bigger and better 6.4 custom parts.
 
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Strokersace

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Thanks guys. I'll head to the bolt store tomorrow.

Yes I ran into the same thing you did last year footlong. Bought a ported intake for a motor last year and the bolts that were sent with it were too long. Luckily I still had the motor on the stand when I realized it. Bought new ones then but couldn't find my extras!
 
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