Pre Turbo Drilling

[JStordahl]

Members: After drilling the hole in the manifold do you cut the threads all the way through? I presume so, since the manifold can't be very thick. How far into the exhaust stream does the probe go and is this adjusted simply by turning the probe in until tight? I haven't bought the gauges/parts yet, but like the looks of Auto Meter. Thanks for your help.

 

[Ladders]

When tapping the threads, remember they are PIPE thread and tapered so you dont want the "sleeve" to stick into the flow of the exhaust gases. The threads should let the pipe adapter "bottom" but not extend below the inside of the metal. I tapped and fitted until the adapter was level with the inside (took turbo loose). OH, and make sure you use the CORRECT size drill bit for the tap size..... been there done that wrong - just double check and double check. The manifolds are not CHEAP to replace. And dont forget the Anti-sieze on the threads.

The probe should go about 1/2 way into the diameter of the chamber, some say less, but the instructions (AutoMeter's) were 1/2 way. Make sure it doesn't go in and touch the other side as when it expands, it could break (small chance BUTT!).

That's about all. Do a search on "Gauges" (some are misspelled and will be missed) and there are more "options" then you could imagine as to how to do it. You may want to ckeck the Products, 12v, and Archives forms also, with the search.

Simple job but take care, some have "cracked" the manifold after awhile and dont recall the reason (could be the hole was "mis-drilled"). You can tap both sides and then start with the probe in the front. Then check the temps at the rear and decide which to use (most use the rear chamber). I tapped both with the intention of using 2 probes to average the temps, but never got the 3rd probe (use before and after switch). The probe that Autometer recommended is the 5244 as it is a "faster" acting probe. Originally had the 5243 probe and it was a slower reacting unit. Their site is: http://www.autometer.com and they are very helpfull if called and you want to discuss the differences in the probes, etc.

SOTSU!!
\\BF//

EDIT: for misspelling
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"Drifty" is a y2k SLT L. E. 2500QC/SWB/5sp w/PTO filter kit/3. 54LSD w/Mag-Hytec/Ultimate bed spray/camper&tow/Ball valve oil drain/25. 5k 5th hitch/muffler&resonator STOLEN?/Nerf bars/E-Brake/etc
47k+ @ 1100. 4 hrs in 19 months.
Not Stroking, BUT, RAMming it Home! SOTSU!! aka \\BF//

[This message has been edited by Ben Stair (edited 05-09-2001). ]

[This message has been edited by Ben Stair (edited 05-09-2001). ]

 

[LSMITH]

^^^^^What he said^^^^^ Three turns by hand is the right depth.

 

[JStordahl]

Thanks for your advice and help.

 

[trbotrk]

The instructions that came with my pyro said to tap the hole untill the fitting screwed in about 3 turns. Hope this helps.

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99 2500,etc,ddx,qc,slt,ez K&N,gauges,lsd,3. 54rear,flowmaster, tow a 13k 5er.