EGT Tapping in Manifold

[mooserage]

Is it best to just drill and tap it? Or get a bung welded in? thanks guys.
-shamus

 

[BluFalcon]

On a 2G or EVO 3 manifold, I've always drilled and tapped a hole for the EGT probe on the raised portion of the #1 runner where one of the upper heatshield bolts goes. Probably not the ideal location, as far as probe placement goes, but it's thicker there than any other runner and has plenty of material for the tapped hole.

 

[SleepinGVR4]

Also if your not taking your manifold off the car, coat the drill bit and tap with grease to help keep the shaving from getting down in the manifold.

 

[mooserage]

I'm actually using a Brand New (in the box if you want to know /ubbthreads/images/graemlins/devil.gif) Evo III Manifold, so I will be doing this while I shave the step off the outlet anyway. So, you guys would advise against tapping say at the main collector area?
-shamus

 

[Vman911]

The evo 3 manifold should have a egr tap in it. Atleast mine came that way.

 

[mooserage]

I don't think they had stock EGT sensors, although I could be wrong. But, I only have heat shield holes, no EGT taps.

 

[Barnes]

These manifolds are not tapped from the factory. Nor is anyone's heatshield. You gotta make holes in both yourself.

 

[mooserage]

Well, I figured those things are true, I was just responding to Vman911's post. I'm really just looking to find out how most of the guys tap their manifolds. Thanks for the clarification though.
-shamus

 

as far as location is concerned...You want it as close to the head as possible on runner 1. You're looking for the temp of the "exhaust gas" from the combustion not the manifold or collector

 

[mooserage]

Cool, thank you for the input. Number 1 being the one closest to the driver? (I always mess this up...) When I am drilling and tapping it, I know I should use a carbide bit, but is there a certain lube I should use when drilling/tapping? Thanks.
-shamus

 

I find it best when drilling cast metals to drill a pilot-hole first, probably an 1/8th inch hole for what you're doing, then drill the larger hole. I typically use tap oil.

 

[mooserage]

Okay, cool, so drill a smaller diameter hole (1/8") all the way through, then drill out to size using tap oil. Thanks.
-shamus

 

the pilot hole will help keep the larger bit from walking around on you.
also, its best NOT to drill too fast or press too hard...one or the other. otherwise you'll end up burning up drill bits.