Thanks SB, I have some ideas too. Glad I built the cart - could have wrecked it just running it inn the boat like that.

Budman,,what you need to do is take the headers off,,find out what size those holes are,dind a piece of rod like a short screwdriver,,take a oxy and ceteline torch with a brazing tip,warm up the fron and read of each water dump port,,,whenits glowing red put the short screwdriver and pull it towards the back side of the header so the water is forced to go out the tail pipe..it would not hurt to put a water diverter on the back side of those holes...i would also try restricting the water hose's going to the headers..

I think the cheapest fix is weld in some type of deflectors. Simplist would be flat stock bent like a funnel and tack welded in front if the holes and extend a couple inches past. Doesn't have to be the full circumference. Just area of dumps. Would a dam be enough if welded as far forward as possible along the bottom? Might be enough to stop the forward flow

Mike, good point about the exhaust blowing the water outward, but conversely, you also have the reverse pulses wanting to pull it back in.

yep ,those headers must be junk .How much do you want to sell them for?

Yep, I was thinking about welding in a dam, not sure if it should go in the collector or further back in the header body. How tall can I go with one of those before it starts affecting flow?

Do you have an engine that you want to drop a couple of exhaust valves on?

Seriously, a good friend of mine has been running a virtually identical set (divorced collectors) for about 12 years now with several big cammed engines, with no issues (that he knows of). I need to get over there and look at the tips on his to see if they are different. Speaking of divorced, that's the way I'm going to end up if I keep spending time and money on this damned thing without seeing it float. We have a cabin rented on the lake in less than two weeks.

Bud something to consider. The smaller the holes are in there, the more psi will build, and the more spraying effect you'll get out of them. Like a garden hose. If you screwed a nozzle on there with a 1/4" hole, it will shoot 30ft away. If you take the nozzle off and let it free flow, it will pour water out maybe 1ft away.

What about welding those old holes up, and welding in a 90 degree elbow, dumping the water towards the transom? Keep in mind, the discharge MUST be large enough, like at least 3/4''. Too small, and you will have high water psi once in the boat, as the water coming from the engine needs to discharge properly.

You are right, MT. That's why I figured I needed to dump some of the water overboard. I have a water pressure gauge on the manifold to monitor block pressure while it is running on the hose, and haven't seen it go much above 8 PSI. I was planning to either tee off of the logs feeding the headers and dump it from there (easiest fix), or weld in a bung at the top of the collector and bleed it off there. That would probably be a better solution because it ensures that there is plenty of water cooling the pipes. I'm not as worried about having a lot of water going out the tips and the exhaust hose. I think there are a lot of guys on here who are just running a small stream of water through the tips to keep them cool. I could use some of the high temp silicone hose for insurance.

Thanks for the ideas, and keep them coming. That's what OSO is all about. We'll figure this thing out eventually.

Well, my welder buddy is out of town for the weekend, and my welder is not set up to weld stainless, so just for testing purposes I gobbed some silicone in 4 of the 5 top holes in the collector. I think this might hold against the pressure if it is not too high, and I can dig it back out later. BTW, I measured them and they are close to .4 inches in diameter. I'm going to experiment with it like this tonight, and I'm also going to fashion a makeshift tee off the water line feeding the header to control the amount of water going through it. We'll see what that does and proceed from there. I still think some kind of reversion dam or turbulator type feature in the collector would be helpful too. I'll take a little bit less flow if it will keep me from screwing up my engine.