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Old 07-06-2021 | 12:20 PM
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Guys, I having my CMI tails setup for O2 bungs. I tried doing some searches but didn’t get anywhere.

What side are you installing O2 sensors? I’ve seen a couple people reference doing the odd bank but with a single plane intake #8 is the farthest away. Does it matter? I have twins so maybe even on one, odd on the other?

Either way, looks like I’ll need to have them inline with then water inlet. Not a lot of room. Pic below is pre-carb builds.

Thoughts? I’m headed out shortly to drop off pipes.


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Old 07-06-2021 | 12:44 PM
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Id do all four pipes then cap the ones you are not using, 2 to 3 inches aft of the jumper hose should be fine, orient them so they kind of face each other on each engine is what Id do,
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Old 07-06-2021 | 01:13 PM
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Here is where I mounted mine. Sensors not installed in this picture but you can see where they go. These were installed by CMI. Sorry for the mess I was finishing this years engine install.
Good Luck


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Old 07-06-2021 | 01:25 PM
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I have mine at approximately 1 o'clock with the bung 1/4" off of the band. Mine have a 1" ring before by the band. It worked great on the dyno.


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Old 07-06-2021 | 01:31 PM
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Got it. Much appreciated guys!

They’re marked 2.5 inches down from the jumpers.
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Old 07-06-2021 | 01:36 PM
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Originally Posted by Rookie
I have mine at approximately 1 o'clock with the bung 1/4" off of the band. Mine have a 1" ring before by the band. It worked great on the dyno.

Wish I had the room outboard. It’s really tight against the sides. Wrenching anywhere around that area is a major pain.
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Old 07-06-2021 | 01:37 PM
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Hey Gary, off topic but did you still need an HP500 filter head?
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Old 07-06-2021 | 02:51 PM
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No it would not fit in the space I had. I modified my HP bracket to mount the Merc std head and added a temp sender to it. I used the Hardin 7 plate oil cooler that mounts onto the flywheel cover. All very tight but turns out very clean.
Again before clean up and detailing.


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Old 07-06-2021 | 04:19 PM
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Nice!

Mine took a whole different turn with locations on a lot of stuff. I made new brackets for everything on the backend. I have my filters vertical because there was no room at all with the monster oil cooler. End to end it’s about even with the inside of the header tubes.




I hope it all fits back in the boat! Lol

Anyway, sorry to have hijacked my own thread. I dropped everything off at the fabricator this afternoon. I should have the pipes back Friday. I went ahead and had all four done.




Last edited by TomZ; 07-06-2021 at 06:06 PM.
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Old 07-06-2021 | 06:37 PM
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Here is the location of mine (before putting the extender on). About 10 o'clock, odd bank. I would also plan ahead for installing a bung extender/heat sink such as this linked below just in case you need it. This cured my issues of having water short out my o2 and I was lucky enough the o2 cable still cleared the hatch.

Heat sink/extender: Innovative HBX-1



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