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Lots of alloy boats with delta pads but typically ones that use axial pumps as the intakes are designed for a flat bottom boat. They work fine for jets if the boat is designed correctly. They most certainly give more lift than a radius keel altho as has been mentioned they definitely arent as easy to keep a pump loaded at high speeds.

The Taylor pic is good, here's another. Usually the delta extends almost all the way forward to where the stem starts curving up. As you can see this actually means the keel is "tapered" towards the back in relation to the height of the hull at the chine. Sprint boats have delta bottoms
 

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Nope, no shoe.

My shit is bolt on:D



How do you trim back a loader.
2 sav I cut mine back with a hack saw and a file. Of course a plasma cutter would have been easier. Mine was hanging 3/8" below the keel, when I trimmed it back surprisingly both my intake suction housing # went up(top and bottom).
 

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That loader is way deep. Needs to be trimmed back.
This is the biggest problem with a delta bottom that I see. I realize they can be made to run 93 mph, but a lot of times it takes so much loader below the delta pad on a fast boat to make it load the pump that it can be dangerous on shut down. They can be made to work. It's just easier with the regular radiused jet bottom. I was not tryinig to knock anyone's boat because it had a delta pad; rather trying to explain the difference.
 

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Steve , put you boat on flat clean level surface (Garage floor etc) Then run a good straight 3 to 4' edge on the keel ahead of the loader intake area , holding the straight edge in place agianst the where it intersects the front of the intake area check the horizontal leading edges of the loader ramp blades versus the top edge of the straight edge (also extend it back and check the center biting edge of the shoe, even if your shoe is "fixed", always curious ) you can use a sawzall or ? to trim the loader blades then grind to reshape or if neccesary they can be welded to add material as well . try to get a "eyeball" as to where the backs (trailing edges) of those ramps approach the face of the impeller also we find lots of them wrong (weld or jig issues). btw this is different for Deltas :) Tom

btw it looks like you may have the original 1/4 x20 bolts on the loader? recommend you overdrill and thru bolt use a little silicone as thread locker and sealant on the loader pad too

PS your loader looks like what we call a "river racer" type , check it real thoroughly for weld integrityalso recommend you drill and tap your suction for intake data readings too
 

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I have a 1983 18' bubble deck Bahner that has a box in front of the intake. Its roughly 2' square. Is that a delta bottom? Should a post a pic to clarify?
 

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I have a Cole 20' SS with a delta pad bottom. When I installed a river racer style intake grate, I gained about 5 mph. My tip of blade hangs down 5/8 inches. That seemed kind of deep. My boat really likes the extra water. Should I trim this back? Looking along the angle iron edge it aims the water at the base of the shaft. Is that were it should be? One thing I did notice is that the loader is built for a intake for a v-bottom . Mine is flat between fins. The fingers of the loader sit slightly below the biting edge of the intake. Is that a problem? Boat rides nice.
 

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I have a Cole 20' SS with a delta pad bottom. When I installed a river racer style intake grate, I gained about 5 mph. My tip of blade hangs down 5/8 inches. That seemed kind of deep. My boat really likes the extra water. Should I trim this back? Looking along the angle iron edge it aims the water at the base of the shaft. Is that were it should be? One thing I did notice is that the loader is built for a intake for a v-bottom . Mine is flat between fins. The fingers of the loader sit slightly below the biting edge of the intake. Is that a problem? Boat rides nice.
I am of the mindset of "if it works, leave it alone", however to properly answer your question, some data logging would be in order, without intake pressure readings it is virtually impossible to say for sure whether or not you are at the optimum point...5/8" sounds deep to me, but 5MPH is huge IMHO...

GT :)hand
 

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Delta

The trick to making a delta pad to work is that you have to go down and get the water unlike a radiused keel bottom. The delta rides on top of the water and the radiused keel breaks thrugh the boundry layer of water and loads the pump. That is why you run the shoe slightly above the keel and with the delta you can run the shoe below the keel.
 

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Pink Taco
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I have one on my 18' 1983 Bahner. I guess that answers me about the droop. Would that make it ride better, gain a few mph?
ur hull is very similar to mine (79 brendela) cant give exact #'s from adding the droop due to a energizer kit at the same time after the jacuzzi wj seized. but the boat changed dramaticaly, i say go for it when u redue ur pump, at the least u will get a way better roost. 229.jpg

025.jpg
 

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My 77 Brendella has a delta pad. I will be installing a shoe and a rideplate. Should I start out with the shoe even with the delta pad and then shim down from there and how much is to much below the padwhen adding shims to the shoe? Also I was told by a few people not to do a set back on this boat, but they couldn't tell me why mabey you could shed some lite on this subject.

Thanks,
Ironman

The trick to making a delta pad to work is that you have to go down and get the water unlike a radiused keel bottom. The delta rides on top of the water and the radiused keel breaks thrugh the boundry layer of water and loads the pump. That is why you run the shoe slightly above the keel and with the delta you can run the shoe below the keel.
 
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