Drilling & Tapping Exhaust Ports For Pyro Probes
 

HAVE TO DRILL AND TAP EXHAUST PORTS ON BIG CHIEF HEADS FOR DUAL PROBE PYROS ANY DO'S, DONT'S ,TIPS ... THNX IN ADVANCE :cool-smiley-027: HAVE A NEW SET OF COBALT BITS READY FOR MORNING

dont do it put them in the headers weld the fittings in them in

Why is that JIMKID ? thnx

I have put them in mercruiser cast, revolution aluminium and Lightning aluminum headers, cant always get ideal placement, but usualy good enough (3/4 - 1 1/2" from port.

Just start withe a small bit, if you hit a void then it's going to be the water jacket. Plug that and try closer to the port.

Hotrunnin Skater Brotha, I am doin the same thing you are. I called Dart. They told me drill top down on the exhaust Port that pertrude the cylinder head. You will not have any water in that part of the casting. By the way what temp do you find optimal?

Thnx Pro if we drill the last 1/2" where the head mates to the header that would have to be dry or it would be weak that close to the end of the casting ..... We ran the 31 AT at 1500 degrees, the Eliminator we kept at 1400 and these motors with the Alcohol will be OK at 1450 ... Livorsi has a nice dual probe set-up :cool-smiley-011:

just remember only 1 case of beer before drilling, 2 could get sloppy! :evilb:

Yeah BIG Daddy NO SLOPPY HOLES :cool-smiley-011:

I would think we'd get a hotter/true temp reading at the head then in the header with water already cooling :D my .02 maybe Mr Horsepower is up and will chime in

the water doesnt come in untill obout 2 inches out from the flange on the headers and thats where we put them to me a lot easer just drill and weld but thats up to you and as far as good reading on the dyno we put them in the header 2 inches from the flange just my 3 cents