Hi I have a spare HPI K4.6 engine sitting around. Can anyone tell me where i can get a water cooling head to fit this engine? and what size hull should i use with this engine and will it be fast?

maybe custom made, or an improvise one by winding a copper tube around the cylinder head..

try rigger or a mono with open hatch to answer the heating issue.imo.

thanks for the reply,I think it is actually a HPI F4.6. I take it that it is not possible to simply purchase a water cooling head to suit this engine? ie like this... <span style="font-family: Verdana, Arial, Helvetica, sans-serif; line-height: 18px; ">http://cgi.ebay.co.uk/Aluminium-wate...#ht_5109wt_722 </span><div><font face="Verdana, Arial, Helvetica, sans-serif"><span style="line-height: 18px;">
</span></font></div><div><font face="Verdana, Arial, Helvetica, sans-serif"><span style="line-height: 18px;">i don't know if this would fit
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</span></font></div><div><font face="Verdana, Arial, Helvetica, sans-serif"><span style="line-height: 18px;">I've been involved in nitro cars for some time however am new to boats.</span></font></div><div><font face="Verdana, Arial, Helvetica, sans-serif"><span style="line-height: 18px;">
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They don't even say what engine it fits ,pretty lame ad I'd say but what do you expect from e bay.