Im building a huge model boat with 2 zdz 210 engines with a 34 inch prop or may use a 3w 240.Does anyone know how many pounds of thrust these engines put out?.....just a rough idea

Send a PM to RCBUGMAN on here.... 'thrust' will vary of course, but he will be able to tell you something close. He's got a lot of experience working with large 3W engines.

I don't know if he has played with pusher configurations, so be sure to let him know if you plan to use pusher props instead of pullers.


Chad

You will need to know what revs you can get to calculate the thrust, go to MVVS.nl and look at the left hand side of the thread under Misc there is a prop/thrust calculator on an Excell spread sheet that may help, its very good.

Mike

for the ZDZ, estimated HP at 5000 rpm is 17
prop 34x16 will give about 130 km/h top speed, and close to 93 lbs thrust

for the 3w. estimated hp is 19 at 5100
prop 34x16 will give about 135 kmh, and 95 lbs thrust

At 5000 rpm, the 34" prop may already be noisy. Noise limit is about 4400 rpm.
The estimated hp may be optimistic for 5000 rm at 0.8 hp per liter engine capacity. To get this power, you need a good muffler system.