I got a great deal on 496 manifolds and my 7.4 manifolds are fresh water but 10 yrs old i am changing them out for the 496 manifolds but not sure how to hook up the 4 cooling lines from the 7.4 system to the 496 manifolds can anyone help?

Just convert it to the new style two tube set up.

You can either get a new T stat housing that only has 2 outlets or you can T the 2 hoses on each side together on your current setup.

thanks i was going to put the 2 hoses that went to the risers to the end of the 496 manifolds and put the other 2 hoses at there normal bottom position but if t ing them would work that sounds easier

I personally would just grab a new t-stat housing. Cleaner installation.

can anyone tell me what year the t stat changed thanks in advance

It depends on what engine.

Aftermarket SS Tstat housings are about $200 each and Diamond Performance has about the best price I have seen.

thanks i think that may be an option and it would make a cleaner install but i was wondering in my current sytem are all 4 hoses flowing water? and if so will the 2 hoses system supply the same volume of water to the manifolds?

Pretty much, the same amount of water will flow to the exhaust. The difference is that the bypass is all internal on the 2 hose housings. Water pressure may increase slightly.

Eugene or anyone have any pics of the old style to the new style with the hoses??
Just found the same deal on a set of 496HO exhaust manifolds to replace my cast hogs.

Thanks, JB