496 exhaust on a 7.4
 

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.

t stat
 

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
 

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:)

new style has only 2 hoses going to the manifolds makes everything much cleaner all the work is relocating the oil filter and shifter bracket i put them on the transom

Is there a way to incorporate the 496 exhaust if you are running the 4" log extensions between the manifold and the riser? sorry for the hijack

I've seen taller risers, but I'm not sure how much taller they are over standard. I've seen them on Formula cruisers with Captains Call like on my buddy's 350 SS.

prepare for sticker shock

http://www.ebay.com/itm/Mercruiser-4...s_Gear&vxp=mtr

http://www.ebay.com/itm/Mercruiser-4...s_Gear&vxp=mtr

cool that they make it but daaammmm that is pricey. better off getting the cast aluminum version of the iron exh for the same price as the 6" riser kit. thanks

i will get some pics tonight and you do need a new therm housing you can buy them on ebay stainless around $200 cast for $50 to $100

just remember; your old t-stat housing is just as rusty as your old manifolds. you may want to check the water passage across the front of your intake too...

Okay, sounds good. Gotta go with the bling!:drink:
Thanks guys!