Exhaust manifold studs

Tw1g007

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2002 Mazda Protege5
I have a header on the way and I want to get new hardware for it since stock is garbage. I wanted something with corrosion resistance. I'm looking at getting a set of APR-400-8013 studs, but that's only four and I don't know what else I'll need. Would two sets of those work? I know there's only two studs stock but I don't feel like tracking down the bolts because it took me half an hour just to find the studs lol. Please help a noob find parts for his old car!
 
Why studs, and what's wrong with the OEM stuff? Mine are still not rusted after 14 years, and work fine with my aftermarket header.

Be wary of stainless. Most stainless alloys are not hardened, and tend to corrode other metals that they come in contact with. Bad news for the cylinder head.

If going the ARP route, I would just get some steel bolts with a black oxide finish.
 
I suppose I could see what condition they're in. I just see the heat shield bolts and how jacked up they are and figured I need new hardware.

I'd do the black oxide but I don't know the Product Number to look them up.
 
Why studs, and what's wrong with the OEM stuff? Mine are still not rusted after 14 years, and work fine with my aftermarket header.

Be wary of stainless. Most stainless alloys are not hardened, and tend to corrode other metals that they come in contact with. Bad news for the cylinder head.

If going the ARP route, I would just get some steel bolts with a black oxide finish.

I just checked the factory hardware... It's rusted pretty bad so I'm gonna want to use new hardware... Do you know what I could use? I'm still having trouble tracking down the hardware and I'm tempted to try to use studs for the whole manifold lol... Stuff is so expensive.
 
Can I use all bolts for the Header, or do I HAVE to use the two studs? Because it would be easier to just use bolts since I'm having trouble finding studs for the car.
 
If you're mounting an aftermarket header, you'll want studs. It would be very difficult to get the egr lined up and the header flange and gasket all lined up.
 
A pair of studs really makes the assembly easier to put together. However, it can be done without them.

Metric hardware store bolts are usually 1-2 dollars each, and make sure you get hardened grade 8 bolts. M8x1.25 is what you need, close to 38mm long. You may only be able to get 40mm.

Autozone/Orielly's may carry what you need as well.
 
So I could use just bolts, but studs would be best? My studs still look fine, but I'll need new nuts for them. As far as the bolts, M8 1.25x40mm will work then, I have some exhaust paint I could hit the heads of the bolts up with to help prevent corrosion.
 
So I could use just bolts, but studs would be best? My studs still look fine, but I'll need new nuts for them. As far as the bolts, M8 1.25x40mm will work then, I have some exhaust paint I could hit the heads of the bolts up with to help prevent corrosion.

Yep.

You may want to double check the header to make sure the flanges are the same thickness as the stock manifold. Bolt length will need to be changed accordingly if they aren't.
 
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