O2 Sensor spacer plates???
 

Does anyone offer these for stock Mercruiser center style exhaust manifolds. I have seen that Dana offers billet aluminum O2 sensor adapter plates for their Dana big block exhaust systems. Basicall just a 1" or so thick plate that would bolt in between the stock manifold and the stock riser with an O2 bung welded into one of the sides. It seems like it would be fairly simple and would allow wide band O2 tuning to be used for lots of boaters. I have a small block (320 EFI) setup that i am considering doing some sort of aftermarket ECU setup on, but would need a way to check A/F ratios while tuning since i would be starting from scratch basically. I know I could get some Lightning headers with the additional O2 bungs added, but I have a hard time justifying $3,000.00 headers for a $10,000.00 boat. Besides, everything I read on this forum states I should not go any faster or make any more power without spending LOTS more money on my setup (it already runs over 70 with a stock Alpha SS drive and no hydraulic steering) and I really don't want to spend a lot more on this 20' boat.

Anybody have an answer to this question? I know there is a guy on here that either had some made or made them himself, but I do not have the time or equipment to do that.

I could get a quote for a set if you would like.

Jeff

I have the hardin/gil marine tailpipe set up and I built my own with 4" SS pipe and some 3/8" SS plate. If your not going to keep them in you could have any machine shop build the same out of regular steel. I would not think the cost would be to high. SS is getting kinda pricey these days.

fastestbowtie

I just started a small machine shop.
I am a performance boater and a Aero-space toolmaker/ engineer with a cnc machining center.
I can design and build anything you want.
I was just on the phone today with Bob Madara and mentioned making the exact part you are asking for.
I will be advertising these along with custom carb spaces in the OSO classifieds soon.
P.M. me if you would like to talk about this and be the owner of the first set.

Jeff Wagner
WagsEngineering inc.
Mentor, Oh

There was a guy on ebay selling them, I bought one when I had stock manifolds, Doug has it now, I think it was around $49

Here ya GO!!

http://cgi.ebay.com/ebaymotors/OXYGE...ssoriesQ5fGear

CP performance i

Actually mine are for an 87 model 320 EFI. I am assuming these are the OEM manifolds, though that is not certain. The dyno sheet indicated they were dyno'd with dyno headers and indicated that the boat was also equipped with headers. Problem is I am the 3rd owner and the first 2 are deceased, so finding answers is a little dificult.

Here you go Man!
http://cgi.ebay.com/ebaymotors/OXYGE...item48359c010e