how else would you expect to measure exhaut temps? there are already three sensors in the stock exhaust (O2 before the up-pipe, EGT in the up-pipe, and O2 in the 2nd cat) so it's not like there aren't holes in your exhaust system already.

in short, yes it's safe.

 

just make sure you get all of the shavings out of the header b4 you put it back in. brakleen and compressed air work really well.

 

i prefer acetone to brake cleaner, you don't get as high...

 

i may be dumb but can you just use the o2 sensor bung? i heard of someone doing that once...cant remember where or if he was just blowing steam though

josh

 

i guess in theory you could use the O2 sensort bung if you really wanted to, but you'd loose your O2 sensort (obviously) and the temp sensor would be much farther downstream than would be ideal. tapping a hole in the manifold isn't that big an issue thought.

 

That's just how gauges are installed. But be very sure to get all the shavings out.

 

you need a new one. just have a competent shop drill and tap a hole in the header, and install the gauge.

 

Not to sound ghetto here or anything, but when I installed an EGT gauge on my Talon I turned the car on then drilled into the manifold. With the car idling it blows all of the shavings out as you drill. Of course, there is a chance to get some up into the turbo, but probably pretty small. The two questions I have is has anyone ever tried this on a WRX and had success; and is the stock manifold cast iron or something else?

 

I hear ya theworx, but I wouldn't want to take that chance.

I'm an idiot and I did this without help or any problems by removing the manifold and tapping on the other plenumn adjacent to the first o2 sensor... I did this after removing the passenger side of the manifold. Just make sure you have the right tap and the right drill bit size for the tap. Finish all metalwork and clean and clean and clean until you think you've really overdone it. And although theworx's idea isn't bad, it sure is much harder than drilling the pipe w/ it detatched

jason

 

I am coming back to this thread 6 months after posting origianlly, but where is the correct cylinder mani to tap? I think 4 from what I have heard. Which one is 4?