On the stock manifolds there is two water lines to each side, one to the manifold and one to the riser. There is an internal port for the water to go from the manifold to the riser. On the stainless marine ones there is a spot for one to the manifold and then there is a short hose connecting the manifold to the riser. There is no spot for the second water line in the riser. There is no internal port for the water to go from the manifold to the riser if the short hose is disconnected. So is the one water line into the manifold enough and if so what do I do with the extra line?

Thanks

install threw hull fittings&send the water out the transom.easy to do.

most guys buy the thermosta ss replacement it has one line instead of two. if you need to use what you have put both lines at the bottom of the manifold .the one that is at the bottom now goes to the back and the top one goes to the front but I think you can get the replacement from anyone for 100 bucks or so and is a lot better.

You need a Y fitting to connect the two hoses on each side.

yes or that diamond has the thermosta housing too.

So I can run both lines to the bottom of the manifold, one front and one back? Why do most people go to a single line? It would seem to me that would not cool as good since it would be the same size line right? Also if I'm running double lines into the manifold its still a single line to the riser from the manifold, does that matter?

thats how I have seen guys run it who didn't want to spend the coin, me I would run the sta from diamond, thasts what I run on my 650hp motor for 12yrs with the cross over that kit is more and you don't loose hp to the water pump on the front of the motor. I would do the single.

call diamond up he has great prices I am getting my throttles from him this summer and valve covers, best price I could find.

I would buy the crossover kit ,,like airtime said !!!