Exhaust port retap

[JustAnotherVictim]

Ok so it seems somehow the last two ports on one of my cars head were stripped.
Now I'm trying to see if I can retap it. I don't believe getting another m12x1.25 tap will actually make any difference the closet size available is m12x1.5 but i will have to drill a hole 31/64 so I can use the helicoil kit. Is this a good idea? or is there another alternative.

some pics
The ports that are stripped


Exhaust bolt compared to tap size

 

[IJ.]

Grab a helicoil kit in the right size JaV.

 

[JustAnotherVictim]

So an m12x1.25. I gotta search some more for it then, m12x1.5 is the closest I've found around here, only thing is the tap for all of these looks around the same size as the pic cuz the heli coil is supposed to go inside the new tap right? I'm assuming that means tapping the head is ok then.

 

[IJ.]

The kit will come with a Special Tap that matches the outside of the Helicoil and the inside thread will be the same as stock.

 

[JustAnotherVictim]

yea I have the kit, but I was trying to confirm that it's ok to actually drill a hole in the head that big

 

[IJ.]

JaV: Good thing you asked!

Who told you it's 12x1.25?

It's actually 10x1.25 (just went out and double checked)

The Helicoil kit tap for 10x1.25 should just about work in the stripped hole without drilling.

 

[JustAnotherVictim]

ok cool I'm not sure where I heard it I thought it looked a little big.
Thanks IJ

 

[IJ.]

Very welcome JaV!

fyi: 12x1.25 is headbolt size

 

[JustAnotherVictim]

maybe that's why I has that in my head

 

[IJ.]

LOL the manifold would NEVER leak if ya did em all 12x1.25 <jk>

 

[Joel W.]

as a suggestion, do all the exhaust stud heli coils while your there and you can get to them easily...

 

[JustAnotherVictim]

I did consider that
thanks for the suggestion

 

[Ckanderson]

Grab a helicoil kit in the right size JaV.

:agreed: