Fellow Modellers, does anyone know what the best prop is for a Texas Speedfreak 45". Boat has race modded Zen 260pum. Have tried Duggan Sim3 and Propworks West 7016 (3). These both work but the boat is flighty, even running wet. Straight line is fine but boat wants to drop the bow and inside gunnel at the slightest turn of the wheel. Boat runs stinger surface drive, inner and outside tabs, turn fins and long offset (5") rudder. Any constructive suggestions would be appreciated. Can send transom photo if this would help. Thanks.

What you have discribed here, the answer could be "HOW HIGH IS UP", but some pictures would help a lot.

I would start by setting all the tabs at zero, or parallel to the running surface. If you find some chine walking in the straights, you can very gradually lower the inner tabs 'till it stops. Rudder vertical angle can help turning attitude. If your bow is dropping too much in a turn, put some positive in the rudder ( bottom of blade toward the transom ). Depending on the hull, it may not need a lot. The 7016 is a good prop, but if it hasn't had the lift removed, it can lift the transom ( drop the bow ) and cause bad habits in the turns. Fins can cause problems if they are not aligned with the keel. Even though they are mounted on 90 degree brackets on the transom, they need to have a long straight edge held on the fin ( clamp ), and a measurement taken from the keel line to the back of the fin, and another from the keel line to the straight edge up near the bow. This is part of the set-up often over-looked.

Thanks for your prompt responses. Some photos attached. Boat runs 4" stinger, trim tabs are set parallel to and approx 1/16" above running surface. Rudder is mounted on a 5 1/2" standoff and is at right angles to the bracket (no forward or rear offset). Starboard fin is set deep, port one at half. Engine is at 13 1/2 " from transom at COG. Thanks.

Hot Rods, I am interested in your comment about fin setup. As I am unfamiliar with the measurements you mentioned, can you please provide a little more info. Should I be trying to establish that the fins are tracking dead-ahead? If not, ,what I'm looking for. Thanks.

Yes, you want your fins dead parallel to the keel. Also, some monos work better through the turns with a rectangular shaped fin. They have more surface area to hold the water better. The fins should only be in the water through a turn.

Your first description has me a little confused. You say the boat is fine down the straights. And you said it's flighty, even while it's running wet. These are contradictions. It either runs wet, or it's flighty. And if it's flighty, it's NOT fine down the straights. ???? A mono will drop the chine/lay over with rudder input. That way they carve the water through a high speed turn. Then they should pop back up down the straights.

Sorry, like the boat, my language was a bit loose. The boat does run fine and straight, on the last 1/3 of the running surface, in a straight line, it is the dipping and overall twitchiness when cornering that is the problem. When I say "even when running wet", I have lowered the tabs and prop to wet the hull and this has made no difference. I have looked at the fins - this could be a problem. Thanks

That type of turn fin does weird things in corners you want more of a square fin - also being 'kicked back' like in your picture doesn't help - doesn't work then till deep in corner



like so





www.ccracingengines.com/index....742&id=29402427

Thank you Rod, your advice has been most helpful. I have adjusted the fins using the technique you described - one was badly out of alignment. I am happy to ditch the curved fins in favour of the square ones you have recommended , I see they are available from CCracingengines. As for the prop, I'll stick with a rounded ears 7016? It'll be a couple of weeks before i get the fins from OS but will report back after trials. Thanks again,

You can't go wrong hooking up with Carlo.

All the best for your testing, and don't forget those suggestions on rudder angle to fine tune the set-up. One change at a time is the rule LOL