I just got a second hand procharger 5psi setup for my 7.4 mpi bbc... I know cast internals ect... tic tic tic , I also got the optional fuel pump and regulator ect.. the tech I spoke to at procharger about the kit recommended that I install an afr gauge just to be on the safe side (seems to make sense) detonation sucks!! however I am still running wet exhaust with the corsa quick and quiet deal and plan to for a little while. because of the wet exhaust the procharger tech said to have a 1'' spacer made to go between the engine block and exhaust manifold and drill out a spot in the spacer for the afr sensor. And then of coarse you would need longer studs ect..I am just curious to see if anyone out there has done this or run into something similar. Any advice other than dont procharge the 7.4 HA HA ..would be great! thanks

IF you go to ebay under Moore Performance sells one out of aluminum for about $100.00, would work great for fresh water use but brackish or salt water it will not last to long

Here's the least expensive one on eBay.
http://cgi.ebay.com/ebaymotors/OXYGE...item2eb4fef8bf

Thanks, I know its only an inch but would force my exhaust out of alighnment? do i need to do the same on the other side?

There's a guy on here that makes them, very high quality. Can't remember his scree name, but search the classifieds, he had them listed there. With any luck, he'll see this thread.

If it is the HO motor then the internals are GM factory forged. If not HO then yes cast. For the most part if Merc says Mag it is cast and if they state HO it is forged.

Cool. Good luck on the charging.

I will leave my opinion to myself since it seems you do not want to hear about what happens to cast pistons.
Be sure you use a wideband kit, the narrow band is not very accurate. I have used both and wideband is the only way to go.

HI what is the afr a stock marine engine should run. ex 496 HO.thank

Jeffswav,
thanks... I ordered the wideband kit today from summit racing
PN: avm304100

I make oxygen sensor spacers for merc style exhaust.
Let me know if I can help.

Jeff Wagner
Wags Engineering