Bigger Manifold Stud

[SIMGSX]

Well, we all know how easy the manifold studs break all the time. And i decided to get SS studs just becacuse they needed to get changed. So found out that one of them was already been helicoiled. So therefore, i was thinking just to drill out that stud to the bigger size to solve the problem. and i was just wonering if there is any feed back about the whole idea.

 

[3kgt2nv]

technically a helicoil is stronger than threading cast aluminum. the thread engagement is better on both sides and if the heli coil becomes worn or damaged it can be removed and replaced.

A lot of racing teams in f1 and open wheel racing preemptively helicoil alot of bolts that see constant work like exhausts and intake studs.

besides a bigger tap means courser threads. ideally you would want a tighter thread pattern like a m10*1.0 or m10*1.25 both are very rare taps that your going to pay 30-50 bucks for as metric fine thread is only used in high stress spots like strut tops and head studs on some cars.

most m10 bolts are m10*1.5

 

[weaponx122412]

Yes I agree. Helicoils are better. & you also have to keep in mind the size of the bolt holes on the manifold itself. If you drill & tap the head to large then you're screwed. Although the corner bolt holes on the manifold are bigger than the center holes. & usually its the upper left stud that snaps, so if need be you can drill it a little larger & tap it to 3/8" & the stud will fit through the hole in the manifold. Hope this helps.

 

[bryanwheat]

technically a helicoil is stronger than threading cast aluminum. the thread engagement is better on both sides and if the heli coil becomes worn or damaged it can be removed and replaced.

A lot of racing teams in f1 and open wheel racing preemptively helicoil alot of bolts that see constant work like exhausts and intake studs.

besides a bigger tap means courser threads. ideally you would want a tighter thread pattern like a m10*1.0 or m10*1.25 both are very rare taps that your going to pay 30-50 bucks for as metric fine thread is only used in high stress spots like strut tops and head studs on some cars.

most m10 bolts are m10*1.5

M10x1.25 is actually a very common tap size. My 10 dollar harbor freight has that size tap and die. Every bolt on these cars that is 10mm is a 1.25 thread pitch.

 

[3kgt2nv]

i am sorry you are correct about that. i thought i typed m10*.75 and m10*1.0

 

[SIMGSX]

Becuase I do stock at the shop the bigger studs so since the hole can't be helicoiled again, I should just mechine out the head stud hole a little more and tap the bigger stud in there. Also my manifold hole to match the stud and call it a day.

 

[weaponx122412]

That's what I did. We stock some studs at my shop as well. When I took off my manifold to replace the broken stud, I also removed the exhaust housing of the Turbo & the O2 housing at the same time so i didnt have to take off any cooler lines on the Turbo. Then I drilled out the broken upper left hand stud & tapped it to 3/8. Worked out beautifully. Of course I also removed the long stud off the Turbo & replaced it with a bolt upon assembly. & I put a ported 2g manifold back on & I ported my Turbo exhaust housing & O2 housing while I had em off.. but the 3/8 stud worked just fine since it was a corner stud.

& very true, u can always just make the holes on the manifold a little bigger to match the studs...

 

[SIMGSX]

Cool yeah im going to give it a shot and see how it goes. but i think i really and no choice or ill just have a nice exhaust leak with a missing stud. Thanks guys.

 

[stracer107]

Another thing you might want to consider is thermal expansion. So if you are going to go bigger studs you also need to make you manifold match. If your hole in the manifold are the same size as your bolt you risk shearing the bolt. So allow a little room for expamsion.

 

[SIMGSX]

Oh yeah, ill make sure that they both match. It will be pretty simple i think with the tools we have here.