Gilligan
X-
- Location
- LANDLOCKED
Tom I am surprised no one is jumping on that x-jet hull after seeing those videos.
gp800 66e motor???
- Thread starter aqua
- Start date
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Freestyleriverrat
Guest
Thanks for all the info Tom, it is really helpful.
waxhead
wannabe backflipper
- Location
- gold coast
Great video
but it looks like an awful day with all that wind about
but it looks like an awful day with all that wind about
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Freestyleriverrat
Guest
Found this on groupK's website:
The cylinders on the GP 800 are unconventional by pwc standards. Instead of an aluminum cylinder with a thick iron sleeve, the aluminum cylinders of the GP8 have a thin layer of hard plating for the piston to reciprocate in. Yamaha calls this plating "Yamaha Ceramic Coating", but it’s basically "Nicasil" (a nickel-silica plating). This thin, but super tough, bore diameter has a much lower friction coefficient than iron, thus allowing for much quicker piston acceleration. This thin plating also makes for a much more conductive-friendly path for the heat of the piston to get to the water-jacket. The material of this plating is so tough that it can stand up to the forces of several piston scoring "episodes" with virtually no damage to the bore at all.
again......interesting :scratchchin: It is a well know mod but I did not know the 800 had it.
The cylinders on the GP 800 are unconventional by pwc standards. Instead of an aluminum cylinder with a thick iron sleeve, the aluminum cylinders of the GP8 have a thin layer of hard plating for the piston to reciprocate in. Yamaha calls this plating "Yamaha Ceramic Coating", but it’s basically "Nicasil" (a nickel-silica plating). This thin, but super tough, bore diameter has a much lower friction coefficient than iron, thus allowing for much quicker piston acceleration. This thin plating also makes for a much more conductive-friendly path for the heat of the piston to get to the water-jacket. The material of this plating is so tough that it can stand up to the forces of several piston scoring "episodes" with virtually no damage to the bore at all.
again......interesting :scratchchin: It is a well know mod but I did not know the 800 had it.
And if you big bore it, you put regular sleeves in, or if you get it ported you have to get it replated.
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Freestyleriverrat
Guest
more from the site: http://www.groupk.com/y800gp.htm
The Swift Kit - This kit is a small collection of the most effective bolt on parts for your GP 800, along with modification of your stock cylinder head. The GP 800 Swift Kit makes for a big increase in overall acceleration, and a 1.5 - 2 mph increase in peak water speed. This is the ideal kit for the owner who is looking for an easy and quick way to bolt on a significant improvement in power and handling. (92-octane compatible).
Sleeper Kit - The Group K GP 800 Sleeper Kit allows your stock looking, and sounding, GP8 to accelerate and top end right along side a GP 1200. The huge increase in overall torque allows the GP8 to bolt out of high-speed turns with no bogging at all. The 3.5 - 4 mph increase of the Sleeper kit puts this lightweight on a par with most of the top muscle-boats. The 92 octane compatible Sleeper Kit includes all the same bolt on parts as the Swift kit, along with Sleeper cylinder porting and cylinder-head modification (carburetors need not be removed).
The Swift Kit - This kit is a small collection of the most effective bolt on parts for your GP 800, along with modification of your stock cylinder head. The GP 800 Swift Kit makes for a big increase in overall acceleration, and a 1.5 - 2 mph increase in peak water speed. This is the ideal kit for the owner who is looking for an easy and quick way to bolt on a significant improvement in power and handling. (92-octane compatible).
Sleeper Kit - The Group K GP 800 Sleeper Kit allows your stock looking, and sounding, GP8 to accelerate and top end right along side a GP 1200. The huge increase in overall torque allows the GP8 to bolt out of high-speed turns with no bogging at all. The 3.5 - 4 mph increase of the Sleeper kit puts this lightweight on a par with most of the top muscle-boats. The 92 octane compatible Sleeper Kit includes all the same bolt on parts as the Swift kit, along with Sleeper cylinder porting and cylinder-head modification (carburetors need not be removed).
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Freestyleriverrat
Guest
Yeah....but it is kind of trick to have that on a stock motor out of the box.
- Location
- St Augustine, FL
You don't need to resleeve GP800 cylinders when going to a larger piston. You can bore them to 84mm or even 87mm and just replate them. On GroupK's 1390 kit for the GP1200, they just bore the cylinders to 87mm and replate them.
And you don't need to replate cylinders after they are ported. We port plated cylinders all the time. Almost all current snowmobile cylinders are plated. And we never replate cylinders after we port them as long as the plating was good when it came in.
It can get expensive though if you do need to replate a cylinder. We charge $195 to just replate a cylinder and if the bore needs to be welded at all, it costs $235 instead.
And you don't need to replate cylinders after they are ported. We port plated cylinders all the time. Almost all current snowmobile cylinders are plated. And we never replate cylinders after we port them as long as the plating was good when it came in.
It can get expensive though if you do need to replate a cylinder. We charge $195 to just replate a cylinder and if the bore needs to be welded at all, it costs $235 instead.
- Location
- St Augustine, FL
If you install cast iron sleeves into it, you wouldn't need to plate it anymore. It would be just like a 61X cylinder and if you can find oversized pistons, you can just bore and hone it. But by installing cast iron sleeves, you loose the heat transfer advantage that you had with the plating and if you use GroupK's 87mm piston, good luck finding a oversized piston you could bore it to. You could use some SEA-DOO 951 pistons but you need to find the right wrist pin bearings to make them work.
The OEM cyl comes plated, no sleeves.
For a big bore, you can bore out the plating and use regular sleeves instead.
- Location
- South Africa
Is this thread about the gp800 engine or the wb800 engine that was last attempt that yamaha at winning the sport class...Coz I had one of those new blaster(it sucks only because the weight of the dam thing...)putting that in a blaster1 with twin pipes=142hp with just a pipe added.....stock is 120hp...but i cant remember if it had powevalves....il keep reading this thread..
- Location
- South Africa
I have an article in old splash that compares all the blasters1,2,new....il scan and post later...Blair Gillispie was the racer and rider at the wf.....
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Freestyleriverrat
Guest
Not sure on the wb800, all the info I have found has been on the gp800........although there were some differences between the years.
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Freestyleriverrat
Guest
A cheaper route is the groupK Sleeper package. Sounds promising b/c it is designed to give good increases in power from low to mid rpms. That mod is only 450.....pretty much standard porting price and the cylinder gets a fresh bore and hone. At minimum if you do porting for low end power, the pipe, carbs and say a conservative 170-180lbs compression it should be rockin. pretty hard and pumping out at least 160hp :bigeyes: That is just from my guesstomometer :haha:
- Location
- Hutchinson, Kansas
i'd prefer to run the nikasi plating to save the weight of the sleeves. It's a better idea for heat and it takes much more than a light seize to hurt them. however you can modify port timing slightly with sleeves. on the nikasi versions you'd have weld up the cylinders and replate them to change anything. Once I find my idea setup I might go through and do this for weight savings. I got a quote from group k one time for their big bore setup and it was reasonable. I like Group K's and Lamey's big bore 66e package because it includes a modified stock head and stock head gasket, this is the best way to keep water from entering the combustion chamber. I've have many problems with my riva big bore head sealing water with the orings. I've have several custom sets of domes cut to try to solve this, but it is still happening, not as often but enough to bother me. I'm actually running 88mm pistons out of a polaris snowmobile right now.
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Freestyleriverrat
Guest
Pics of ported 62t and stock 66e cases just for reference. Pretty much the same except for size. I need to see some 66e cases in person. Looks like they have a small cut out near the reed cage assembly that feeds the transfer ports.........similar to a ported set of 62T's. This is not a great shot of the cases
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douglee25
m3booooy
- Location
- South Jersey
Nikasil plating is usually around 0.002" (OEM) to 0.006" (aftermarket US Chrome). Aftermarket plating usually lasts for about 100 hours.
Doug
- Location
- sunbury ,ohio
66e pipes
yes there are options to the 66e , you can use harrys ported sleeper, we can chose big bore from several companies , bump compression by shaving the head and fixing the squish , thats been proven and reliably dooable if you stay with the stock type headgasget, again several companies can do this ,the stock pipe is good to 927 cc '''i believe 87mm correct me if incorrect ,, if you go bigger than 927cc your stock pipe is no longer effective , so we have everything we need to get tons of power and every body has great ideas that work with ''choices ''!!! presently there are no CHOICES for pipes ! we need pipes !!! factory made the twins that were proven monsters but with no demand they quit making them !!the down side was those pipes were for the gp hull ! not the sj or b1 hull , what are the choices on the sj pipe or b-1 pipe or pipes with a 66e in them ??? nobody is making them that i know of except waterdog who suposedly makes one for the sj but thats a single pipe again with limited cc ! so will somebody fill me in on pipes since huge cc's are no problem for the 66e to handle ! the stock pipe weighs a ton and puts a lot of unnecessary weight above the waterline !! so lets talk pipes and get the weight down !??:frown: :banghead:
yes there are options to the 66e , you can use harrys ported sleeper, we can chose big bore from several companies , bump compression by shaving the head and fixing the squish , thats been proven and reliably dooable if you stay with the stock type headgasget, again several companies can do this ,the stock pipe is good to 927 cc '''i believe 87mm correct me if incorrect ,, if you go bigger than 927cc your stock pipe is no longer effective , so we have everything we need to get tons of power and every body has great ideas that work with ''choices ''!!! presently there are no CHOICES for pipes ! we need pipes !!! factory made the twins that were proven monsters but with no demand they quit making them !!the down side was those pipes were for the gp hull ! not the sj or b1 hull , what are the choices on the sj pipe or b-1 pipe or pipes with a 66e in them ??? nobody is making them that i know of except waterdog who suposedly makes one for the sj but thats a single pipe again with limited cc ! so will somebody fill me in on pipes since huge cc's are no problem for the 66e to handle ! the stock pipe weighs a ton and puts a lot of unnecessary weight above the waterline !! so lets talk pipes and get the weight down !??:frown: :banghead: