1 engine. Kind of steep...:eek: :(

I must be lucky. I have now run my o2 in my cmi for the last 3 years. I do check & make sure the O2 passes the fast test from time to time.
I had a local guy do mine who welds on custom motorcycles. He did a good job. If you have time I would send back to CMI. That way you will know for sure it was done correctly.

pics of mine, pipes are dry

I'll bring this thread back up because I just had a stainless bung welded into my imco risers for the 21SB. Only costs $32- thanks IMCO!:kiss:

I searched around for others that have had it done to wet exhaust... I have some very minor reversion at idle it appears. I ran it on the hose and got a tiny drip out of the bung after idling a long time (it was finger tight) I pulled it out and sure enough tiny bit of water at idle is getting back to it. I pulled everything back apart and double checked... looks good/no leaks. I'm sure its due to the cam and feel more confident about it now after reading this. I have some slip in mufflers that might help get the velocity up at idle and external flaps I can install, maybe all that will help some to keep water flowing to the rear? Either way, I was suprised to have the minor amount of reversion- I've never messed around with o2 sensors in marine applications till now (I was an outboard guy)

Oh yea, I'm just running the o2 to get fuel mapping checked out, not perm.

Just spoke to IMCO... they quoted $132 per tailpipe plus shipping... not $32...special discount?

I don't remenber for sure, but I might have run it thru one of the guys I buy parts from out west....he is right down the street from imco... I don't have the reciept, but I do have a charge on my credit card where I bought parts at that same time from him and the times all match up for when I got the bung welded in.