Pre turbo give you a much more accurate temperature measurement. If it is post turbo, you are basically guessing the temperature.

 

Thanks for the input, But wouldnt it be better 2 remove the turbo before drilling the manifold i would be kinda scared of drill filings. will the magnet thing work for the long haul? just curious

Thanks

 

We pre-drilled a pilot hole w/ grease on the bit. We then greased the main fitting bit, wiping the surface clean at intervals. One through, I used a magnetized screwdrive and fished around in there removing soveral chunks of metal that did get free of the grease. I quit when I stopped pulling metal back out on the magnet. Then a greased tap to run the pipe thread in there, and a little more fishing then we called it done.

 

After seeing two turbo impellers that were warped after drill chips stopped them dead and the exhaust overheated them I always remove the turbo now.
Guess I shouldn't say remove, I just remove the four bolts that hold the turbo to the manifold and slip a piece of cardboard in-between. After drilling and tapping start the engine for a couple seconds to blow the chips out, make sure airfilter is in place as chips will fly. It's actually faster this way than fooling around with grease and magnets, plus you are certain all the chips are removed.

 

Thanks for the input. I think I to will be removing the Turbo.