Exhaust bolt torque?

Scaaty

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Anyone know the proper exhaust bolt torque for new center rise on a 350SBC? Specs for the riser bolts in the boxes, but none for exhaust. Thanks.
 

Bondo

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Re: Exhaust bolt torque?

I'd say about 45/50ft.lbs. according to my calibrated Elbow,............. ;)
 

Haut Medoc

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Re: Exhaust bolt torque?

Bondo, not trying to be a wise a$$, butI always thought it was 25#.....And if I am wrong please correct me...Is O.M.C. different in this respect? I have always gone by Merc. manual #9...But mine is old..Has the spec been changed or have you learned something with experience? I always feel like they could be tighter, but....I get scared to really tighten them down that much...Please advise....JK :confused:
 

Don S

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Re: Exhaust bolt torque?

Are these Merc, Volvo, OMC, Barr, GLM, Osco, or XYZ-brand manifolds and risers? And on what year & model engine
 

Bondo

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Re: Exhaust bolt torque?

Well,.......<br />They're held on with 3/8ths" bolts,.......<br />3/8ths" bolts are torqued to 35ft.lbs. Normally,....<br />With a bolt that's What,?? 4" or 5"s long,.... That's Alot of bolt to Flex,......<br /><br />So,.... I tighten them to a standard torque for a 3/8ths" bolt,+ then give it another slight Snug,......<br />That would get it to About 45/50ft.lbs......Which is standard torque for a 7/16ths" bolt.....<br /><br />No,... I don't break out the torque wrench,+ Shop Manual..... <br />This I'd do with my Snap-on flex-head 3/8s ratchet........And My Calibrated Elbow....... ;) <br /><br />Even if they're held on with Studs,.... I'd torque them the Same Way.............<br /><br />If I'm wrong,... Correct me........<br />But,... I've Never had an exhaust manifold fall off an engine,+ I've Never Stripped out a Head.........
 

TilliamWe

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Re: Exhaust bolt torque?

Bondo, ah yes, as father says, "you ain't gonna break that bolt, get it tight!" <br />I have never heard it referred to as the "calibrated elbow" before. You crack me up Bondo!
 

KaGee

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Re: Exhaust bolt torque?

LOL....<br /><br />Where can I send my elbow to get calibrated? It's off to the high side! :p <br /><br />Robbie.... Around 35 is the spec i see posted around for manifolds. I did the "Bondo" method on my risers. Couldn't get a socket on the forward 2 bolts.
 

Scaaty

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Re: Exhaust bolt torque?

Originally posted by Don S:<br /> Are these Merc, Volvo, OMC, Barr, GLM, Osco, or XYZ-brand manifolds and risers? And on what year & model engine
Aqua Power.. 96.. 350SBC
 

Scaaty

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Re: Exhaust bolt torque?

Originally posted by Robby6950:<br />
Originally posted by Don S:<br /> Are these Merc, Volvo, OMC, Barr, GLM, Osco, or XYZ-brand manifolds and risers? And on what year & model engine
Aqua Power.. 96.. 350SBC... and grade 5 bolts
 

Scaaty

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Re: Exhaust bolt torque?

I can get at these bolts real easy, so I was thinking about 35#'s, then the calculated elbow after running, and a continued checklist item until saltwater has its way again.
 
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