300/440/550 Mariner 300 Pipe to hot!

Hey I just put a Mariner pipe on my 300sx and its a very similar setup to the Kerker, the issue I am running into is my chamber gets SUPER hot! The headpipe cools just fine and is routed like the Kerker, I was wondering if anyone else has ran into this issue? Ran great before with the stocker and my 38mm SBN, now its boggy and won't rev up in the water? Just acts like the pipe is getting way to hot! Jetting was spot on before, almost sounds rich to me, but it just worries me with the pipe getting way way to hot! Thanks for any help!
 

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that motor is cute....lol sorry it just looks funny with only one cylinder...dont worry i am laughing at my self as well since my first ski was a 300sx......check the inlets of the pipe and make sure none of them have been tapped for jets....(like a restrictor of some sort)....over the years someone could have modified it, pipe looks to be in great shape unless you just polished it...check out all the in's and outs of pipe just to make sure nothing blocking or restricting and let us know....btw that pipe has hardly no bottom end and made for peak rpm.....what jets are you running in that 38sbn?
 
I have no idea what jets are in the carb, just bolted it up, adjusted needles, and ran perfect on the stock pipe. There are no water restrictions at all, I checked that already. The head pipe stays cool, but its the chamber that gets smokin hot, like dirtbike pipe hot! The pipe looked like brand new when I bought it. Trouble is there is no water spraying through the chamber to cool it, noticed the Kerker is setup the same.
 
I cant speak for the mariner pipe having not tried it but it does look similar to the kerker that im running. They do get hot being stainless and spraying bugger all water into the actual chamber!

On mine I did away with the stock venturi and used the thru hull line to run dual cooling from the pump. I have the stock cooling line running as normal but the second line runs cold water directly to the headpipe manifold without being pre-heated by the engine. The manifold stays nice and cool and it does help keep the chamber temp down low enough that i can touch it without geting burned.

hope this helps!
 
Yeah would be sick, Get a little water injection going. I have the Kerker pipe but have not run it yet. Bought the ski for dimes... Ill let you know on the temp once I throw it in the water.
 
At least your blowsion air filter looks cool! All i can think is maybe the small water jet holes inside the header pipe are blocked. They spray water direct into the chamber like how a b pipe head pipe works on a superjet only the mariner and kerker are not adjustable. If those holes are blocked up the chamber will get super hot and the ski will have terrible bottom end power. The holes will be hard to see you might have to remove the manifold. Good luck!
 
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