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:smile2:OK - I did a few searches and printed off some threads and even pulled out my new bright red fomoco shop manual. Got the torque sequence down pat and the "cut the head off 4 - 4" or 5" bolts for corner guides trick dialed in.



My manual says to torque the stock 2 bbl cast iron manifold down to a max of 14-16 ft lbs.



I do have a question or two -



First on the threads the max torque is mostly spoken to as 18-20 ft lbs - but I did not see any differentiation between cast iron or Aluminum.
So I'm wondering if the 2 -4 extra pound feet has to do with Aluminum manifolds or just rounding off?


Next has anyone used the eBay Deepmotors 4bbl Aluminum manifolds???? If so any issues or torque specs?


I know its from china- but it is the cheapest new manifold I could find and did not find any used inexpensive 4 bbls manifolds anywhere close from where I am (50 miles is close to me) that wasn't premium $$.



It did look like a lot of the Deepmotors manifolds were being sold and no issues that I could find - it also looked like this manifold was being sold by quite a few on ebay with marked up prices.


In my case I need to get a Parker Funnel WEB manifold off of my Falcon wagon (302) so it is drive-able where I live. So I'm finally just gonna do it and HOPE it works OK>


So any info on intake manifold bolt torque or specific to the Deepmotors manifold will be much appreciated.


LBM>:)
 

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14-16 should be fine, but you'll need to keep going over the torque sequence again and again until the values are consistent. The torque sequence starts in the middle, and works its way to the ends... But, after you get to the end, the gasket relaxes, and the center bolts won't be nearly as tight. Sometimes it takes several passes before the gaskets finally fully compresses, and all of the bolts maintain their torque values.

Good Luck
 

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Discussion Starter #3 (Edited)
Great Thanks - 18 or 20 too much???. Makes sense - the manual speaks to 5 pound feet each time until you get to the max - probably because of the gasket flex.


LBM:grin2:





14-16 should be fine, but you'll need to keep going over the torque sequence again and again until the values are consistent. The torque sequence starts in the middle, and works its way to the ends... But, after you get to the end, the gasket relaxes, and the center bolts won't be nearly as tight. Sometimes it takes several passes before the gaskets finally fully compresses, and all of the bolts maintain their torque values.

Good Luck
 

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I wouldn't be afraid of 20, but I would make sure you don't have the Felpro Printoseal gaskets, they are especially leaky on a SBF. Additionally, I have found that the SBF will let you retorque many times as the vertical bolts tend to continue to loosen as things set in. Don't go crazy with it, but walk away, and come back starting in the center, you'll likely find them all loose again for a couple cycles
 

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+1 since asbestos gasket material was banned years ago , the new grey colored material "settles" more after torquing and heat cycling. As Ross mentioned FP printoseals are notorious for this and WILL suck into the port creating a huge vacuum leak. FP has updated them by adding a metal core to prevent the gasket from sucking in. There are other brands like Torque Master that have metal cores too. I have not had a problem since I switched to the metal core gasket and the bolts stay tight even on aluminum heads.
 

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Main thing, is to go over the torque sequence over and over until they hold torque, as gaskets WILL compress. You start in the middle and work your way to the ends, but by the time you get to the end, the gasket will compress to where the bolts in the center are almost slack. This is especially bad with composite gaskets. The ones with the metal core (if you can find them that are big enough for the ports in your head) are much better with this.

I have use Print-O-Seal and similar gaskets with success. What kills them, is they rip as the intake is torqued down. This is largely because the bolts are vertical, and the gasket is on an angle. This causes the intake to slide on the gasket as it is tightened... which can rip the gasket. What I usually do, is GLUE the gasket to the cylinder head, and then grease the intake side. This allows the intake to compress the gasket without ripping it. It just slides wedges down in there and tightens up. Plus, the gaskets are often re-usable.

That being said, I believe I have a small vacuum leak at this time... so use the metal core units if they fit your application, and the head to intake fit is good enough to utilize them. Sometimes you need thicker, more compressible gaskets if the fit isn't square enough, or the intake sits too low on the head.

Good Luck
 

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Intake swap how-to.
 
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