Hole Shot Helpers

[SLOmofo]

Please add to this thread with things you have done that helped and also things that hindered.


Foils I have used. Eagle One Performance big, Johnson medium, Allison smallest.

 

[SLOmofo]

Modifications of clamp bracket and trim cylinder. Mount for cylinder inside set back plate. Allison ride plate and partial of side fill plates.

Beginning steps.

 

[SLOmofo]

 

[whipper]

Thanks for posting that Gary!! Now ya went and done it. I have more projects this winter.:banghead BTW love your exhaust super tramp. :beer:

 

[GotMyAlly]

 

[John S]

BTW love your exhaust super tramp. :beer:

I think Slomofo is more of a Steve Miller fan, lol. You've done some real nice work there. I have a foil like the one on the right, works great.

 

[procomp]

Ive installed over a dozen of the allison style foils and they've all made a huge improvement on allisons, streams, checkmates and stv's

 

[SLOmofo]

A caution in using a foil.

Some don't flex/bend and will break the lower unit's cavitation plate where it's bolted on. I had to have mine welded. It was a large wake board boat day a few summers a ago. Didn't mean to but was air born one to many times. Wasn't an Allison foil, it was one I had made. It was larger in size and thicker aluminum then the Allison foil.
About 1 1/2 months ago I came upon a wake I couldn't do anything but cross and broke the Eagle One Performance foil a year or two before I had to cut the wings off of it because of they almost broken off.

 

[loop]

nice job on the trim system.
How fast is it compared to stock 12 volt Fastrak?

 

[SLOmofo]

Went from 2.5/3.0 seconds to .75. These are 24 volt times the fast track is limited because of small diameter supply. 36 volt didn't do anything except make the pump spin faster, but had no increase in volume. With everything, when there is a plus there is a minus. I now have to use a 6 volt system to do normal trim adjustments. So its now 6v, 12v and 24v.

 

[loop]

How did the Fastrak motor and relays hold up @ 24 volts? Any issues?

 

[SLOmofo]

It's been along time but I don't remember any of them sticking closed and the motor still worked when I removed it. I did/do have a limit switch (Galen) that cuts off the 24 v when it reaches it's set point.
The Fastrack and first looper are limited by the small diameter passage ways, fittings and pipes. Fluid flow is limited by the smallest hole it has to go through. You can have a 10" pipe on both sides of a 1" connection fitting. The 10" pipe will only flow what the 1" fitting will allow through it.
24 v will spin the pump faster and it will push fluid harder it's just limited by flow. Doesn't take much to cob it up and try and then see if it works for you.

The only trouble with a OMC relay I've had is they died open circuit.

The system I have now is solenoids that have silver contacts (less likely to weld shut) Merc trim tab pump and a bunch of other stuff.

 

[hullbilly]

Based on my testing, regarding improving hole shot on an Allison, no substitute for 24 volt trim and a trim timer.

On a xb3003, negative trim wedges in addition to the items mentioned above

On a hard hitting xr, 36 volt trim

 

[SLOmofo]

I've never had experience with a trim timer. That said I would think as battery voltage dropped the trim motor would be slower and pressure would be lower thus less movement for the dialed in time.
I don't compete in organized drag races. But I do prop testing at my local lakes.
What I use is a trim limit switch for the 24 volt up on take off. This is controlled by the EFI computer. The computer grounds a relay which allows voltage to the limit switch and then the 24 volt solenoid once the RPM is over 4,500 and if the throttle is over 90% open. Works out to about 3/4 of a second lag. The limit switch turns off power to the 24 Volt solenoid once it reaches it's set point. 24 will turn off if the RPM or throttle drops below the computer settings.
Allison foil and a 24 Yamaha
http://www.youtube.com/watch?v=HLtSxArOvJc&feature=youtu.be

 

[whipper]

Your motor is soooo nutty!! The instant response on the peddle just lifts your hull like crazy!! Looks like a hand full of fun but hard to hold down because the torque and lift just wants to twist the stern over. Is that about right? Man i cant imagine having 450+hp wacker on the back!!!:gasp:beer: 100mph must be instant, that motor is AWESOME!!

 

[SLOmofo]

With the 24 Yamaha it's not as nasty as a 26 knob cut. Guess the blades flex more and don't hook up as hard at first. A larger ear just after it's on plane just torques to the left and gives so much bow lift it then seems as though it's going to go over.
The people in the other boat both commented on how little boat there was in the water. A foot and the prop. That's why he moved over.

 

[hullbilly]

Gary,

I prefer the timers because I have found that delay timing is critical for dialing in hole shot. I like the mechanical stops/limit switches as well...had one in my xr2001 in addition to the timer/delay box.

 

[SLOmofo]

I can see that a timer would be infinitely adjustable as to how long after the WOT switch is shut and then the timer starts the trim. I just have it stuck in my head that as a battery is drawn down through multiple passes the time stays the same, but the pump doesn't have the same push, therefore the trim doesn't travel as far.
Or am I picking fly specks out of pepper? :wink

 

[hullbilly]

I can see that a timer would be infinitely adjustable as to how long after the WOT switch is shut and then the timer starts the trim. I just have it stuck in my head that as a battery is drawn down through multiple passes the time stays the same, but the pump doesn't have the same push, therefore the trim doesn't travel as far.
Or am I picking fly specks out of pepper? :wink

You are absolutely correct, but, in my experience, it would have to be a very large field of boats before this would come into play. We always set the boats up with a dedicated trim timer battery to hedge against this issue. With the light weight batteries available now, should never be a problem.

 

[LEVI LEDET]

With the limit switch it will trim to the same place every time it just may take a lil longer to get there if the battery's are getting weak pass after pass but I never seen and diff in times on my racepak dash testing making a lot of passes