Hi guys, just bought my first mud motor last weekend, back H2O 35 hp SWOMP LT. I have a 20 inch transom on a 16 ft alumacraft waterfowler and have already put both shims in the cav plate per back H20's instructions for a tall transom. motor wants to come out of water at higher speeds, and I was struggling to get 19 mph at full throttle...will my performance be better if I cut my transom down to 16" and weld a pair of pods on the back of the boat? also I think I am not in the "clean" water at the back of the boat- where the cav plate rides in the water becuase that is where the wash from the bottom of the boat comes out. any suggestions would be greatly appreciated....thanks

How long is shaft ? 19 mph sounds good for long tail

First things first is it a ss or ls?

You should be faster than that. My 1648 War Eagle hits 20-21 with my 23 Back Water.

With the 20" transom, there is a definite issue with the standard 72" or 59" shaft...not sure how those shims supplied by H2O work. Frank is right, you should be running a good 3 mph faster. You can tweak/advance the throttle to 4300 rpm out of the water and realize some gain, but if the angle supplied by the shims is not adequate this may not help. I think all the reviews on H2O have been positive- I am very interested in the SS (59") model's performance.

the model 35 SWOMP is a S.S.

ok then we need to know which hole the frame is in out of the 3 under the motor.

The bolt is thru the middle hole on the frame, that where they put it when the motors leave the factory. Should I change the hole location for the bolt?

try and move to the hole towards the front of the motor that will put more weight on the tail which should help

SS model should be on a 16 inch transom LS on a 20 inch. I have a SS SWOMP with 33 hp generac motor. It runs 25 mph on a 15/48 flatbottom.

That is a heavy short boat with not a lot of flat planning area due to the mod v. you may be able to tune the set up a bit, but you are probably not too far off from your top end.

Mag10

Mag is also right when it comes to the mod. v part in most cases its a preformance killer but it can also be over come in most cases with some time spent.

most profermance ss short ls tall no comparison

Ive been running two side by side a ss and a ls and i do not question jake, larry, or arlon but my 35ls on my tall transom has been out running the 35ss on short transom every time whole shot and all the ss has alot more turning ability at wot. The ss short- ls tall is not in question as far as which one belongs on a tall, but backwaterinc does send the ss for a tall transom for some cases .

Have run both SS is better for my application

I've got a 20 inch transom on my roughneck and they are tellin me to cut it down and get the 59 inch shaft. If I'm not willing to cut it down won't the 71" shaft perform the same? Maybe not turning ability? Another concern is will the 71" shaft reach back to far into that "dirty water" where the wake begins. Any advice on what to get?

If anyone has any questions about the alumacraft waterfowler with the Backwater swomp msg me. Jake from backwater and i spent a day testing my waterfowler that i have with med pods.

I spent a good amount of time on the phone with Jake talking through the same issue. Unlike you though I have a 15" transom.

He said with a 35hp SS, which is what I also have, that it would be a good idea to have pods on the boat if it is 16' (which I have) and make sure you have some weight in the front of the boat. He said if that didn't solve the issue of the prop blowing out of the water then utilize the shims. If that didn't work he said to move the pin to the hole towards the prop. I know moving the pin to the back hole towards the prop contradicts what someone else posted, but I'm just relaying the conversation I had with Jake.

Awesome guys by the way. They won't let it rest until you have it figured out. I'll probably be a BackH20 customer for life.

Ok i had a 35 Backwater SS on my old boat 18x52 Semi V i just sold with a transom height of 19 3/4'' speeds with just 2 guys was 21-23. The new boat I ordered I ordered a 20'' transon. But my buddy is telling me the SS would preform better on the 16" than the 20" Transom and i need to get my order changed ASAP?

thanks

Your friend is right.