I just ordered a Westach dual gauge for EGT. Now I need to order Thermocouples. They have three different lengths. 21/2, 4 inch, or 6 inch. My manifolds have already been drilled and tapped for 1/8 NPT. Which size would you recommend?

I feel I got a very good deal, on the gauge was $59.95 plus shipping, $4.85 USP. I'm also ordering a second gauge, dual pressure temperature. It is an oil gauge, I called Westach and he said it would work for Turbo pressure and transmission temperature. He recommended relocating the pressure switch away from the block. He says at 250° pressure sender will reset itself? The gauge and the two senders they quoted me $105. The only catch is they are back ordered, there will be in eight week delay but I think I will order anyway. Don't plan on towing. For some time.

I like to say thanks to anybody who replies

 

My guess would be the 2-1/2 inch. The longer ones would go all the way across the manifold and hit the other side.

Edwin

 

Isspro here. Mine was about 3" and I had to add abushing so it wouldn't bottom out.