Value question: OEM manifolds or shorty headers?

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buckwild27

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It's a wash man. Do you want Heavier cast iron manifolds or do you want lighter Shorty Headers? No performance benefits as we all know. LT's are out. It comes down to what you want since they're the same price. You'll probably want to wrap them too, thinner metal more heat. Locking header bolts are a must. By the 3rd time of replacing missing bolts or Tightening up the loose ones You'll be wishing you went with the cast iron manifolds.
 

j91z28d1

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do the shorty's they will have a resale value of something. not much market and bad to ship cast iron.


for bolts, don't use them.. use studs. I worked at a mustang performance shop forever ago, when the 03 corba was a hot new car. every one of them got full exhaust. headers and all, not one ever leaked, you know why? cause we threw away the bolts and gaskets that came in the box, reused the oem exhaust gaskets, MLS just like the stock ls are and reused the oem studs with flanged crimped lock nuts.

as long as the headers are decent metal and welds, with at least half inch thick flanges, they will probably out live us on the truck.

you know what size the ls header bolts happen to be? the same m8 1.25 the mustangs used back then. went I put zo6 exhaust on my ls3 car I grabbed 2 sets of Dorman Ford stud kits at the local parts store for 11$ each. they are 10.8 rated and super cheap, you'll pull the threads out of the head long before you break one. arp bolts are nice, but a loose bolt is still annoying no matter how strong the metal is.
 
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Nooo, not stage 8 locking bolts! Those are the biggest pain in the ass. Not only because of the C-clips, but getting the locking tabs aligned usually requires the bolt to be a bit under or over torque, or having to grind it down a bit.

Split lock style header bolts are much easier and are actually cheaper
 
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Charlie207

Charlie207

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do the shorty's they will have a resale value of something. not much market and bad to ship cast iron.


for bolts, don't use them.. use studs. I worked at a mustang performance shop forever ago, when the 03 corba was a hot new car. every one of them got full exhaust. headers and all, not one ever leaked, you know why? cause we threw away the bolts and gaskets that came in the box, reused the oem exhaust gaskets, MLS just like the stock ls are and reused the oem studs with flanged crimped lock nuts.

as long as the headers are decent metal and welds, with at least half inch thick flanges, they will probably out live us on the truck.

you know what size the ls header bolts happen to be? the same m8 1.25 the mustangs used back then. went I put zo6 exhaust on my ls3 car I grabbed 2 sets of Dorman Ford stud kits at the local parts store for 11$ each. they are 10.8 rated and super cheap, you'll pull the threads out of the head long before you break one. arp bolts are nice, but a loose bolt is still annoying no matter how strong the metal is.

Do you have a part number for those studs?

I just stopped at AutoZone, and the only head studs they had in-stock were the wrong thread pitch.
 
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Charlie207

Charlie207

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I just checked with a tap, and confirmed by the assembly manual, and the exhaust manifold bolts are M8 x 1.25, which is different than the M10 x 1.50 that the Dorman parts list, even though they say it's a direct fit.
 

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