Well after the advise of others from my previous thread here:
Need advice on new 401 SBC stroker build

I am looking into Wideband kits but the main question I have is where is the best spot to put the O2 sensor in My Stainless Marine risers? Plus if located in the riser then I have the other issue of the double walled riser. Getting a bung welded in properly through the water jacket seems tricky. Also, the water mixes with the exhaust at the very end of the riser. Can the O2 sensor be located in the aluminum exhaust manifold or is that too close to the head? Be simple to drill and tap a hole in the manifold. See attached images of risers.




Also, any suggestions on a simple kit with a gauge? Would like to put a gauge on the dash.

Any thoughts and recommendations is appreciated.

Thanks again,
Jim

I would pull a riser and put it as close to the exit of the manifold as possible. I can take a picture of what I did to one of my stock Mercuiser risers to get an 02 sensor in it.

Basically drill cut a hole in the outer pipe, 2 ".
Drill and tap the inner pipe to except the sensor, which you may need a bung so that you have more threads.
In that case weld the bung to the inner pipe.
Find a piece of stainless pipe about 2" and cut it to fit so that it slides in the hole and makes contact with the inside pipe, and has enough sticking out of the outside pipe to weld around.
Weld around the inside and outside of the pipe.
Now you have sealed the water off around the sensor.

I will snap a picture of mine tonight.

Makes sense, I was thinking that would be the only way to do it, and getting access to that inner pipe.


The procedure in that link would be a little easier as long as the clearance between the inner and outer pipe is small enough to allow the inner pipe to dimple in. Great info and images.

I have a feeling I wil be doing it the way "Paxtonspeed" did as I think there might be about 3/8"-1/2" between the walls. I will have to drill an 1/8" hole to find out before I figure out which hole saw to start out with.

See the photoshopped image below, are these locations for the O2 sensor adequate? A or B or....



Thanks agian

I would put it here. The further you can get it, from where the water mixes the better.

The Hardin Marine LS engine manifolds are where I got the idea for mine. I pretty much did the same thing in this picture to one of the 3 inch spacers that go under my risers.

Mine are just above the hose

How's this location? Would like to keep it "out of the way" so as not to bump or snag it while working on the engine or standing in the engine compartment.




Also, do I need a sensor for each riser or is one side of the engine ok? Innovate makes a 2-wideband gauge. Link below
https://www.innovatemotorsports.com/products/dlg1.php

where did you get those uprights? or did you modify the ones you had?