Hi me and a budy are putting a Pro Charger on his 7.4 whe pit the water cross over on and now wonder do whe put the thermast back in the new thermast housing that replaces the big Merc. one with 7 lines on it. Any I deas from people with water cross overs would be great THANKS Charlie.

It may take some work to get the system to function correctly, but start with the stock thermostat and 3 3/16" holes drilled in it. And yes, you'll need a aftermarket thermostat housing. Get one with the bypass.

I put on crossovers and tstat housings with a 5/8in restrictor in them this spring oil temp is good with about 110 to 120 water temp water press is 20lb.

140 degree thermostats are available from West Marine......
in the cooler water of Washington, a thermostat may be needed. Procharger does not recommend a thermostat! If you call them, register your charger serial # and ask for a install manual that is specific to your engine......you will get it fedex in 3 days, no charge!!