Tach reading low? (New sensor)

[TWeatherford]

It is on the way. where is the best place to put in in the manifolds?

Most like it between cylinders 6 and 8 (back two on drivers side - which is convenient for running the wires into the cab). They fire one after the other, so thats likely the hottest spot.

 

[icanfixall]

Like posted above. Between 6 & 8 on the drivers side is where many instal the pyro on a non turbo engine. Or weld a bung into the cross over pipe. Drilling the exhaust manifold is easy but threading it can be a job if you have never done a pipe tap tapered thread before. When you tap a taper thread you need to know how deep to push the tap into the material. Not deep enough and the threads wont seal.. Too deep and again the threads wont seal. So thread it a bit and test fit the probe. You want to see two or three threads showing out of the hole.

 

[79jasper]

That's good to know Gary.
When I installed my brothers pyro, I took the tap all the way in. But also it was some weird foreign probe.

 

[icanfixall]

I feel I should add some cleraification to my post. A tapere cut pipe thread seals by interferance with the other thread its being installed against. There is a designed depth to the thread emgagement that creates the seal. Its generally felt the engagement is always the same amount of threads per inch. If you have never drilled and cut a tapered thread please do a test drill and tap. See how deep you need to make the tap go into the material your cutting threads in. No matter what I tap I usually start with a starting tap if I'm taping threads all the way thru something. No need to use a bottoming tap or the tap in between the starting an bottoming tap.. For the life of me I can't recall the name of the tap. So know to cut threads be it machine fine or course their are three taps that can be used. A bottoming tap is used on a drilled and threaded hole with a blind bottom to it. The hole is not drilled all the way thru the metal. Its called a blind hole for short. Its a well known term in the machine shops. I hope this informtion is helpful..

 

[jrad235]

Thanks for the help guys. I'm still waiting on my Pyro to arrive from Stewart Warner, but in the meantime I have figured out that the hill goes from 6% for 2 Miles(Which the truck does OK on) to 9% on the final ascent, I.E. The last 600' of elevation. I don't know any N/A truck that likes that kind of grade. I'll update as I learn more.

 

[jrad235]

Excited! My gauges are supposed to arrive Monday! Hopefully I'll get everything set up this weekend so there is less to do next week.

 

[MidnightBlade]

As far as the low tach reading at idle goes, check for a bad ground. Mine does the same thing but as soon as you get over 1000 it catches back up. Ive tried 3 brand new senders and they all did the same thing, so ground is the only option left.

 

[jrad235]

That sounds like a pain in the ass to track down. Thanks for the idea though. I imagine it would involve taking the dash apart. I may check that when I change the bulbs out for blue. Today I'm going to install the oil pressure sender, and hopefully find some paint that matches this truck!! Don't know WHY I didn't order it a month ago while I was still waiting! probably because I didn't think it would be so difficult to find.

 

[MidnightBlade]

When it acts up give the top of the dash a good hard slap and see if it straightens out for a bit or completely drops off. if it does either that tells you there is a bad ground/connection in the dash somewhere