Thread: My build from 63.5 to 71.2
05-23-2010, 10:46 PM #1
My build from 63.5 to 71.2
It took 5 months to bringing it all together, but after researching, asking Qs and scraping knuckles, i finished my project with great success but final top speed being just little disappointing.But my "game plan" was a strong holeshot that pulls hard(accel) through the mid range, and top speed even though not being the most important thing, somewhere in the low to mid seventies. So here's how it started....
I wanted compression 150psi so i called top engine guru mr horning and it went out that day.But before i started any disasemble i made sure that i only used 12 point sockets (10-12-14mm) on all the work that was getting done.Less chance of any stripping of bolts.I was happy to find that piston wash looked good after taking head off the head..As i waited for the milled head to come back i covered the open cyls with plastic so nothing can accidently fall in.I cleaned the head bolts threads with a wire brush and metal pick , same for the the cylinder threads, also started disasembling the u pipe,stinger, throttle bodies and reeds and that will be discussed later.I received the head back from Osidebill who finished the work on the head.I went with a brand new cometic gasket sparing no expense on something so important.I used 400 grit sandpaper to smooth the mating surfaces(cyl.head /cyl)Then used the old engine builders trick of using similar bolts with the heads cut off like pins to perfectly line up the gasket/head. I've seen Beefdart use this on reeds , and i use pins on my VF3S as well, but will discuss later.On GH there's a few different opinions on what if any what grease to use on both sides of the gaskets.I used marine grease LIGHTLY brushed on both sides and then carefully dropped on the cylinder through the pins.Now with it back together i replaced the pins with the 12mm bolts adding 2 washers per bolt since the head was shaved about 1/16 of an inch and didn't want to bottom out. I used a very small amount of blue locktite on each thread, since i was going to possibly retorque after a heat run which Mr. Horning reccomended. I followed the tightening order star crossing one to eighteen first tightening to 16lbs then around 30lbsI used only a high quality torque wrench(digital), the service manual calls for 28lbs but i went a little over.Everything looked ok and before i had closed it up i sprayed some WD40 on the walls of the cyclinders just a precaution keep them lubed while they were opened.So this ended my first phase of my build
NEXT VF3 INSTALL......
05-23-2010, 11:40 PM #2
- Join Date
- Oct 2009
I tried that trick on lineing up my head and the head cover holes where smaller then the head, glad to see it workedfor you.
05-24-2010, 09:14 AM #3
yeah,you only need about 6 pins spread around, that will guarantee she lines up,i found it more important in VF3 install as you had more parts(5) to line up
05-29-2010, 09:19 AM #4
I purchased the vf3s with the needed custom spacer plate and paper gaskets.These were taken off from a Ski Doo snowmoble, so Rich(wfo) put this package together for me with extra long allen bolts(50mm) that will be needed.First the whole air box and throttle bodies were removed labeling everything and taking pics ,even though the air box will not be put back in.
The reed assembly will now consist of 7 parts to be aware of -intake manifold/gasket/spacer plate/reed cages/gasket/balance plate/throttle bodies plates
It was important that all 22 holes line up correctly to accept all the bolts, that no air leak would be possible.Rich recommended marine grease to put on both sides of gaskets. This will seal gasket on tight and act as a adhesive to keep them lined up, besides preventing water intrusion .But first through GH research, of this mod, the paper gaskets would have to be slightly cut to accept the spacer plate and reed cages All the metal mating surfaces were slightly sanded with 400 grit to make sure all surfaces are flush and smooth with no imperfections.
When the gasket fit was smooth ,i applied gently with a brush, a light coat of lube on both sides
I used ant-sieze on bolt threads since because of high heat in that area,there's a less chance of galling . I would be making all 22 bolts good and tight. I put everything back in the hull and lined everything up by using 9 headless bolts of the same size thread put around the holes of the intake manifold, spread them around to line every piece up and started screwing in, but i had my first problem.It turned out ONLY 18 holes fit, the 4 in the middle on the balance plate would not go through, something wasn't right.I called Rich,he tells me somethings backwards. Sure enough the spacer plate was turned backwards, even though it accepts the cages sort of the same way and the holes SEEMED lined up.By not having the balance plate completely out of the hull, i still have my oil lines hooked up(still oil inj)i couldn't see the error. So i turned it around cleaned the the areas and started again.
I star- crossed all 22 bolts real tight but made sure those 4 bolts fit nice. I finally finished this part of of my rebuild but let me mention i did not perform a leak down test on this install,but feel confident everything is sealed well. Since 6 hrs of riding i've had no signs of bogging,loss of power etc.
NEXT ROSSE'S THROTTLE BODIES INSTALL.....
06-06-2010, 08:08 PM #5
40mm bored out sonic booms
The GPR by nature is starving for air so i wanted to open up more air induction and volocity to the intake manifold.After reading Ross approach for more air intake but no water intrusion,i decided to go all out with his bored out open throttle bodies.The air box, flame arrestors and tubing were completely removed except for the the tubes leading from the cowlings which were cut open from the outside with a box cutter .The tubing would eventually point and be near the throttle body openings.
06-06-2010, 09:23 PM #6
I like the GPR on the flat water and and some mild chop and wave jumping so water intrusion would not be a concern but would have to see how much water gets in from time to time and maybe add another automatic bilge.Ross was great and very prompt in our discussion in dismantling the throttle bodies to be sent to him, those blue stacks are going to look awsome.Like all the other dismantling , pics and labeling were done to remember to put back the same way.The 3 electrical connections were disconnected, throttle postioning sensor, stepping motor and engine temp sensor also the throttle cable.
I remove the metal throttle openings from the rubber boots on the throttle plate side of the reeds which clamped on and are locked in sort of a groove.
Now i would removed the fuel rail from throttle assembly taking out the 3 long bolts, leaving the fuel injectors still attached to the rail since Ross would not be needing them.There are important black o rings that the injectors sit in to spray the atomize fuel, it was important to not lose them.
Now with the throttle assembly now removed from the hull and everything photographed for reference it was off to Ross for a turn around time of a wk.
06-06-2010, 10:03 PM #7
I received back the TBs and could not have been happier, the horn shaped stacks would induce cool air and create a vacuum.The reinstall was pretty straight forward.It was important the the injectors sit nicely in the o rings on the assembly. The throttle metal openings with the ridges around it would ''snap" in to the boot part throttle plate on the reed side and the clamp with the groove would "lock" the throttle bodies to the reed throttle boot assembly given a tight secure fit.Putting the throttle cable back on,Ross felt i was'nt getting a full throttle unless you get a 'click" when you stab it, so I increased the tension on the cable on the TB, also lubed that area well . During the throttle cable recall it might have been left a little loose.All the electrical connections went back and since each has its own matching size there was no way of mixing them up..Eventually the stinger would go back above the TBs and the blue stacks sitting 8-10 inches above the bottom of the hull, water intrusion was almost impossible unless a capize.Now with more compression ,air and fuel(efi fuel controller) i was on my way.....
next jetworks holeshot install........
06-13-2010, 07:08 PM #8
holeshot build jetworks
The GPR has the potential to be the fastest 0-30 ski out there with its power to weight ratio of 170hp/650 dry wt..But with a large waterbox having to discharge lots of water on take off, the Jetworks mod was the must way to go.Its a complex install involving lots of plumbing , tapping and threading holes in the stinger(exhaust).The yr before I installed Leo's holeshot fiberglass piece which had been discussed many times on GH.It fills the void under the rubrail that drastically reduces drag until you get on "plane". Now the two together will give a very strong takeoff.The jetworks has a few "how to" variations and thanks to Hallpass,Jeffsntx and Andygpr(palerider) there builds and pics were very informative.But one thing is perfectly clear,its to keep the waterbox dry on idle and low rpm by exiting the water other than the waterbox, and then bring in fresh water in to cool the waterbox once the rpms reach 2800-3000.
so here we go......
with the stinger removed, there would be three holes made, with one already made and just needing retapped. Now since this install has been discussed and can be found in the "SEARCH" section, all the little details can be found,i'll mention some of the little tips that i picked up.
temp. sensor removed the ''ears" removed for barb fitting that will have the blue jetworks valve that will open up at 3000 rpms to let the incoming water in.
Two more holes were made, one for the water to exit before the water box and a new place for the temp. sensor.A rubber gasket is installed that (is racing kit) blocks the water jacket passages and used to prevent the water from entering the waterbox so its directed somewhere else(stern pisser)Ive read that rubber gasket detoriates over time so i bought a metal gasket (gus13letter) that secures from leaking.
06-13-2010, 07:27 PM #9
The tapping of the stinger was easier than i thought, by first piloting the hole with a 11/32 drill bit and using the required tapping size, its was just "take your time'' and thread through the pipe, and pulling back to take out the material but being careful not to pass into the water jacket.The barb fitting fit like a glove, even i was amazed, i put a little JB weld around the bottom of the fitting to keep the fittings secure with all the vibration.
The out going water, the hose that sends the water out before it would go into the water box was tied into the bypass outlet(pisser)that exits through the stern outlet.A "stealth fitting Y( sold by island racing) shaped was used to tie these two , the outgoing water from the stinger and the bypass hose(pisser) then into one pipe leading through the stern outlet(pisser)
to be continued........
06-16-2010, 04:03 PM #10
Nice thread its gonna help me alot thanks and good luck and achieving more speed ...
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