Re-building a Dunlap W.O.F 30 O/B tunnell hull ?

[Andris Golts]

Hi all i have spent the last month on rebuiding my 10 year old Dunlap W.O.F 30 tunnel hull was origanally set up for Astro 25 cobalt motor on a R.E.K lower unit and 12 nimh cells then switched to 4s with UL-1 power and Seaking 120 amp esc giving 47 mph top speed. First modification i made was get rid of the analog steering servo and the pair of 7'' long 2-56 pushrods with 2 bends in each pushrod to a Hitec HS-5646WP 156 oz torque digital water proof servo with a pair of 4-40 3'' long pushrods running straight into the steering arm. Second modification got rid of the R.E.K lower unit and changed it out for a for a O.S . Max .21 lower unit. Third mod swap out the 120 amp Seaking esc for a Swordfish pro 220-6s amp esc with 6mm bullet plugs and Castle 8 GA wire. My ? here is What max power set up could a 29 3/4'' tunnell hull handle ? There is room in the battery box for 6s1p 5000 mah lipo i also have a Leopard 4082 1600 kv motor sitting on the shelf. Regards Andris Golts.

[JestDanny]

So how's the project going ? What direction you going? What prop, projected speeds? I think a 30" hull on 6s will be entertaining. I've been playing all summer with a little 24" Dumas HS Sprint, set up with a UL-1 motor on a K&B lower & Seaking 120 amp esc, fun boat. The un tested project boat is a AquaCraft VS-1 291/2" tunnel hull. I've got an OSE Raider 36x60 1700 kv on a OSE 80915-v2 lower, esc is a Seaking 120 amp, set to run on 6s 5000mah 50c. Not sure on prop choice, want to start conservative, see how it handles first, ride height thrust angle ? then go for speed prop.

[Andris Golts]

Hi the project is going a little slower than expected i find it more difficult to work on a finished hull as the radio + battery box are being modified i don't want to scratch the painted surfaces as for the varnished area's they have to be re-varnished due to years of use and being struck by another boat. as for direction im leaving myself open to 3 options going 4s with UL-1 or Leopard 3674 2200 kv 5s with a Leopard 3674 1900 kv 6s with a Leopard 4082 1600 kv. For prop im starting with x440 and working up. As for projected speeds thats unkown with 4s + the UL-1 motor and Seaking 120 amp esc and x447 prop i gps at 48 mph. Please keep me updated on the VS-1 project. Regards Andris

[Speed3]

The 4082 will negatively affect the balance of your boat, the extra power could also get it more out of control.

But if you position the cells further forward to get the balance around 33% hull length and maybe use trim angle on the outboard it might work.

[Andris Golts]

Hi Speed3 i was thinking the same thing when i get everything put together i will see where the c of g ends up this is the only motor i have suited for 6s. Regards Andris Golts.