Reply With Quotejer -
Thanks for your comments and I agree ... We do have our measured CG and that's what we're starting to work on in terms of Lifting the back of our boat and potentially installing (in this boat ???) the capsule currently under construction.
jak
"Not to start an argument ... In the case of up nozzle, I can agree with you when you said: "Launch: A droop lowered thrust line may cause more bow rise on launch". With down nozzle I would think the bow wouldn't rise as much ... more force levered about the CG."
Bear, just talking about the affect of a lowered thrust line independent of diverter. But since you mentioned...I think you're right, droop extention will give the diverter more arm if diverters full down angle the same. But what about droop pin angle? I think pin angle (3-7 positive degrees) affects lever arm a heck of a lot more than a longitudinal extension because it changes diverter full down angle. In other words, given the distance between the nozzle and boat cg, changing the thrust angle will change arm more than keeping the same angle and extending the application point aft 7 inches. Does that make sense?
In fact, if we know the geometry and boat cg, it wouldn't be hard to calculate.
jer
jer -
Thanks for your comments and I agree ... We do have our measured CG and that's what we're starting to work on in terms of Lifting the back of our boat and potentially installing (in this boat ???) the capsule currently under construction.
jak
ok droped the plate down 1* to 4 up from keel. Boat got much better. pops up on plane now quick, stays on plane at slower rpm and vitrually no porpoise with diverter full down. diverter up any degree it has a gently porpoise at almost all speeds. I noticed now with the diverter down it doesn't carry the nose and actually feels like it's pushing it down now
so i gather that by lowering the plate it stopped the boat from carrying the nose so high and gave me a back a small amount of diverter control
I am going to drop the plate another 1/2* and take it back tomorrow.
The boat also pulls much less now I did however unbolt the plate and when i put it back on i used a straight egde to assure it was straight with the shoe so i'm not sure if it was the same problem as squirtcha? or if i was just direting the water off the plate directly onto the nozzle.
I'm still curious as to what effect the wedge really has.. I understand it changes thrust angle but what effect does it really have up or down? when I installed all this stuff i've read the droop added 8* up and the wedge 2* so i'm up 10* total from stock and intake was set in at 4* down so i should be at 6* up from the keel with the diverter in nuetral.. with the diverter having to be almost full down i'm sure thats more then 6* from nuetral???
thanks
Glad to hear your tuning is paying off. Just keep messing with it, and you'll eventually find the sweet spot.
ok droped the plate down 1* to 4 up from keel. Boat got much better. pops up on plane now quick, stays on plane at slower rpm and vitrually no porpoise with diverter full down. diverter up any degree it has a gently porpoise at almost all speeds. I noticed now with the diverter down it doesn't carry the nose and actually feels like it's pushing it down now
so i gather that by lowering the plate it stopped the boat from carrying the nose so high and gave me a back a small amount of diverter control
I am going to drop the plate another 1/2* and take it back tomorrow.
The boat also pulls much less now I did however unbolt the plate and when i put it back on i used a straight egde to assure it was straight with the shoe so i'm not sure if it was the same problem as squirtcha? or if i was just direting the water off the plate directly onto the nozzle.
I'm still curious as to what effect the wedge really has.. I understand it changes thrust angle but what effect does it really have up or down? when I installed all this stuff i've read the droop added 8* up and the wedge 2* so i'm up 10* total from stock and intake was set in at 4* down so i should be at 6* up from the keel with the diverter in nuetral.. with the diverter having to be almost full down i'm sure thats more then 6* from nuetral???
thanks
Just for S&G, turn the wedge over and put the big side up top. I am running mine at 4* down wedge, which gives me 3 1/2* up at neutral or center on the diverter. You will like it !!! I have put about 250 miles on my boat in the last two weekends. It is awesome, handles the chop very well, not to mention the three to four foot swells. My set up 4* wedge down and 1* up on the plate and with the lower center of thrust it will run 75 mph fully loaded. That includes 3 passengers, 13 gallons of extra gas, 22 gallons in the tanks, an anchor, two coolers, emergency tool bag, three foldup chairs and umbrellas, a beach blanket, two kids skis, all necessary boating floatation equipment, three fire extinquishers and a partridge in a pear tree.
And BTW, with the Edelbrock 750, I was getting 3.7 mpg, with that load !!!
So im still messing with mine to try to get it to stop pulling. I checked the ride plate and it appears to be square with the pump and shoe. I took my ride plate and shoe off and tried the stock ride plate that came with the e pump today. No luck, still has a slight right pull. Im going to a big get together in Houston in two weeks. There will be about twenty guys from the boards there. Maybe someone can see something i can't.
I may try the down wedge that squirt thunder suggested above.
Kevi
I may try the down wedge that squirt thunder suggested above.
Kevi
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