Just trying to work out the best water pic ups for my 50 inch cat hull.
ive got rudder with one water pic up . are the in hull mounted flush water pic ups enny good to use for good water flow if so do i mount them on the flat runner of the hull or where???.
or am i better of using those ones that fit to the rear of the transum pointing down into the water . or will the flush hull mounted ones pick up good water and have good strong flow at high speed.
motor is a mod zenoah . with tuned pipe , so it has water pipe one for motor one for header pipe (water jacket on exaust is from cc racin, great product ) and water jacket on front of steel tuned pipe. so 3 water jackets all up.
so am i best running seprat water for each water jacket or run them all from one or two pick ups.......if so whats the best way to runn the cooling water ....
i know its a bit of a lame question but i realy dont want to cook this motor .cheers

I have been using prop-blast pickups on several builds lately. Here is how I set them up:

Propblast pickup to engine and out the hull.
Rudder pickup(s) to pipe flange and coupler (if applicable)

I like the fact that the propblast pickup will supply water to my engine independently of boat's actual speed. All other types of pickups rely on the forward movement of the boat for water pressure. That's why I use propblast on engine.

I also have had many boats run all off of 1 single rudder pickup...that works too if you have the plumbing done right. (fittings and rudder drilled 1/8 inch, XL water line)

The under hull pickups seem to work well, but I am not sold on them yet. Have to drill the bottom of the hull, chances of distorting the running surface, etc...

The ones that stick out from the transom are major sources of drag and should be avoided on performance boats. They are fine for sport boats. They supply positive water flow.

The propblast is still the easiest add-on that will not require drilling holes in your boat for mounting...mount it off the strut.

Dual pickup rudder blades aslo offer another alternative for adding a water source.

I also like the propblasts and have been using them lately... way more pressure then using rudder pickup, and a constant flow. It also enables you to switch to a non pickup (THINNER) rudder blade. Less drag!

Im also not sold on the flushmount pickups. I have one (MHZ single pickup) but have been holding off using it as like marc said, theres a possibility in distorting the running surface... not to say it WILL, but just not something i want to experiment with on a perfectly good boat. Wally (Tahoe1970) swears by them, and thats all he runs...and his boats are no slouches.

cheers marc & will , for your info . i just spent the last cupple of days in staling two single flush hull water pic ups one on each hull running flat. took some time to install them right got them flat with the hull after some filing of the edeges of the auminium to get the right depth on both of them so it all sits flsh. then glassed them in .
so i now have 3 water pick up more then anough i think just hope thay pump good as thay say thay do. ill probly run 3 sepreat water lines seening ive got the 3 to use now .
so marc you think its a good id to drill out the rudder pic up to 1/8 so im gessing from entry hole to top . will give it a go . also i think i read that you can also drill out a nother hole on the other side of the rudder for water pick up but it just has to be higher up . have you seen or know of this .....

cheers guys its getting close to goin in the water , just working out where to mount radio box and servos and tinytach every thing els is read to install.
motor is modded . just orded a stuffer crank that i might install at a later day. will run as is till i get it all going and want to go faster i gess...

Yes i normally drill my rudder blade pickups to 1/8inch using aircraft drill bits. They have a more angled tip and have less tendency to drift in the hole. There isn't much material there so it's easy to drill through the side of the blade and ruin it. Be careful.

As for drilling a second pickup a little higher up you can go read the Aeromarine xxx review, there are pictures of this towards the end.

www.modelgasboats.com/Magazine...uterlimits.html

yay it worksB)

look guys thank you all for all the great help and advise.
i hope to have my boat up and running real soon. i hope ive got a ok hull. seening ive got a hull no one seems to have over here . cheers marc for getting the glitch sorted out you guys rock