Have tried to go out with 15 YO son in his Rogers Dragstar and tune the boat.
The engine is running fine.
Trying to tune in the pump/boat combo after a crude throw together get the entire thing going project.
If I am in the boat. It porposises like the biggest piece of shit on the water. To the point of unbearable to ride in.
When I get out, it runs and takes a set and goes like crazy.
What is the deal ???
We drilled the intake to take pressure readings. I can't ride in the boat to monitor them because the boat will not accept a rider.
Damn, Talk about a sensitive setup.
Best bet is to talk to people who have run that Rogers hull and get their setup info, and then make minor adjustments to suit your setup, weight/hull etc as even boats out of the same mold will respond differently at times.
You could get the GPS out and work on max speed, but your best bet is to try and make minor adjustments at the track and use the first season as a learning curve. Season two you can start pouring it on.
I assume you tried to trim the porpoise out?My dads boat has a nasty porpoise to it after a complete re-rig. Boat came with cav plates and no ride plate. Maiden voyage We left the cav plates off(ran out of time) and the rideplate too(forgot it). We are hoping the rideplate will fix the problem as the porpoise could not be trimmed. If it doesn't, we will know why the cav plates were on it to begin with...
This is probably overly obvious ....but as far as watching the gauges maybe you could rig up a vid. camera to record them. I do that when I go out because it's impossible for me to drive wot and watch the a/f, oil pres, tach,pump pres, water pres,ect,ect....
OK Tom here a few pics. Showing where everything in the boat is located. Boat mfg recommended the engine be installed right where it is now. The pump shaft angle compared to the top of the stringer measures 6 degrees.
Held the straight edge on the keel to the ride plate It hit the shoe on the way back. . The back cut shoe prolly needs to go.
You want me to put the straight edge on the keel, extend it across the small area immediately in front of the intake and up to the loader?
There is a short area immediately in front of the intake that does not have the round dropped keel. It's flat. You can see daylight between the straight edge and the bottom of the boat in the one pic.
I'll measure it when we get back from town take a pic and post it up
curious to know where the horizontal lower edges of the loader blades are respctive to the keel and also to the biting edge of the shoe also what the intake opening is front of loader pad to shoe
OK loader blades 1/2 inch below keel
front of loader pad to middle of shoe 16"
But here is the big deal. Shoe dead even with the keel in the center and the back cut portion above keel.
I'll be needing a shoe and shims ASAP.
"Have never had the boat and this long straight edge in the same place before. And also been a little confused on exactly where to lay the straight edge.
It's ugly up that inlet. Ride plate is off to seal up a leak
Were headed out to thrash it some. Don't have any hardware to make corrections with.
On my boat that was too low..I was 3/8"ish(below) and couldn't get shit for pressure, top or bottom. I'm still playing with mine...the pres. taps don't lie. Maybe you drag racer guys set up different...I dunno
Just an obsevation on the loader biting edge, It's sharpened on the top side. Most loaders I've used are sharpened on the bottom side, as to not disrupt the loading/water flow on the top side.
Found out the intake was way too big at 15" Moved the shoe fwd to squeeze it down to 13 1/4" Unfortunately that moves the pump setback fwd that amount.
Had the wrong loader in it. Took the loader that came with it cut out the center blocker and cut it back to just above keel.
Put in a "B" impeller and inducer
Put in new packing and a prime a jet.
Shoe and loader in and out countless times. Pump apart 4 times.
Yes Info Jr. is becoming quite a boat wrench.
Improved the ET by 1/2 second and 4 or 5 MPH
OH and for whatever unexplained reason. Getting the intake pressure up to 40 lbs changing all of that made the 2 person porpoise problem go away.
I usually take a pill...follow the yellow brick road sphss
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