[Eunos Han]

Hey everyone... im planning on getting my turbo installed in the VERY near future. i was going through all the stuff that i had and noticed that i dont have any of the bolts that go from the manifold to the block.

I have an iron cast replica of the greddy manifold which is going to be coupled with a sr20 t25.

i need to know the bolt size/grade for the manifold to the block.
thanks!

 

[Quinn]

You can go to a mazda dealer and buy them there. Also the manifold bolts to the head, not the block.

 

[freedomgli]

Can you reuse your existing exhaust manifold studs and fasteners? If not you can go OEM or you can get aftermarket ones from companies like ARP. Much engine hardware like head studs, exhaust manifold studs (and the stovepipe nuts that secure the manifold) are specially designed for the application. I would not recommend going to your local hardware store with thread pitch/diameter information in hand looking for bolts to secure your turbo manifold. That's just asking for trouble.

 

[2/3rdsCobra]

You can re-use the OE studs, however instead of using stovepipe nuts or drilling/wire tie an OE nut, I recommend Stage 8 Fasteners. They cost $40.00 for the set. You'll have no worries about a exhaust leaks or worse case, crack manifold due to a nut backing off the stud.

 

[freedomgli]

Thanks for the tip. I've never heard of them before.

http://www.stage8.com/auto.htm

 

[Eunos Han]

would the Oem bolts be safe to use? my biggest concern is the bolt snapping and loosening the manifold. this has happened in a friends turbo manifold. He went ahead and bought arp bolts for them after. If the oem ones are safe to use.. ill go ahead and buy them from the dealer..

 

[2/3rdsCobra]

would the Oem bolts be safe to use? my biggest concern is the bolt snapping and loosening the manifold. this has happened in a friends turbo manifold. He went ahead and bought arp bolts for them after. If the oem ones are safe to use.. ill go ahead and buy them from the dealer..

OEM uses studs, and they are fine to re-use, although I do recommend inspecting them to ensure they are serviceable. If not, head to your neighborhood Mazda dealership parts department and order up a set of exhaust studs, then get the Stage 8 nuts w/locking cam.