masterblaster
X-H2
I posted this in another thread question about what screw to open,Im more interested in hearing what some of you do with finding the sweet spot in the top screw and how much water pressure you apply to the head pipe cooling. Since alot of guys have found out that water injecting the pfp in the mani direct from the pump with 1/2 lines DRASTICALLY improves low end responce and power of even the largest of motors,Im wondering how many are injecting the b pipe similarly with added drilled in manual injectors or at least setting up the stock water injectors for best pressure and spray patterns
I find the amount of turns out a given screw is on a particular head pipe means very little once you are open more than 1/2 to 3/4 turn.The pressure you supply to the b pipe has a HUGE effect on how the power band comes on. the pressure you supply is effected by a few things,from the size pump fittings all the way up to if you plum the pipe on its own cooling line,to the pressure on the jetworks valve and the size restrictor you use in the other side of the y split from the stinger overboard. I also find that setting your top screw to the perfect spot where the screw is down just enough to give you a really fine spray mist makes the best response,this is usually less than 3/4 turn out. I hook a garden hose necked down to fit the lower cooling inlet,I use the cooling line out of the ski with the y fitting and restrictor and jetworks valve installed to set for that sweet spot. put a gauge on your cooling line coming out of the head pipe and find your default pressure with your ski in water and nose into the dock and full throttle or if your brave ride it with the hood off to get a true reading. even certain cylinders and heads effect pressure as well as the size and number of cooling fitting you use on them.,one other thing I have had success with is using half inch fittings and cooling lines from pump to mani and then 3/8ths outa the head,if you dont run a split cooling system,keeps pressure high but doesnt over cool cylinder,otherwise just run 1/2 inch straight to the head pipe from the pump
One of the days we were tuning the true performance 965,on a newly ceramic coated headpipe,I found out some retard threw in the tumbler and got polishing balls all inside the water jacket....after riding a few min on couple b pipe water screw settings,all the sudden the power came on MUCH better for low end and responce.I noticed I had lost cooling to the top pisser,the one coming off the y split to jetworks valve. took it in and found that a bead had gotten stuck in the top cooling line and totally closed it off. This increased the pressure in the headpipe and made a huge diff. Some others there thought the diff was just cause the pipe heated up and the water box dried out. Ive found that with a jetworks valve,riding around testing low end response and power,they dont open much at all,same test nose in to dock at full throttle blips with jetworks valve disconnected from stinger. check when flow starts..I find a resrtictor on the jetworks valve useful as well. Ive heated the pipe up with almost completly closing all screwss and disconnected the stinger water completely to see if it makes anywhere near as much diff as more water pressure using restrictions to the head pipe outlet with the top screw open and it just doesn't even come close...some people just refuse to get it...try it for yourself.... you will lose some top end and a few rpms but your motor will come off bottom and mid HARD.The motor doesnt stay on the pipe up top,thusly if you or someone else rides your ski and wrings its neck wide open,the motor makes WAY less heat and is way less likely to seize with this kinda pipe setting...win win in my book if you could care less about a few mph on top end racing.
I find the amount of turns out a given screw is on a particular head pipe means very little once you are open more than 1/2 to 3/4 turn.The pressure you supply to the b pipe has a HUGE effect on how the power band comes on. the pressure you supply is effected by a few things,from the size pump fittings all the way up to if you plum the pipe on its own cooling line,to the pressure on the jetworks valve and the size restrictor you use in the other side of the y split from the stinger overboard. I also find that setting your top screw to the perfect spot where the screw is down just enough to give you a really fine spray mist makes the best response,this is usually less than 3/4 turn out. I hook a garden hose necked down to fit the lower cooling inlet,I use the cooling line out of the ski with the y fitting and restrictor and jetworks valve installed to set for that sweet spot. put a gauge on your cooling line coming out of the head pipe and find your default pressure with your ski in water and nose into the dock and full throttle or if your brave ride it with the hood off to get a true reading. even certain cylinders and heads effect pressure as well as the size and number of cooling fitting you use on them.,one other thing I have had success with is using half inch fittings and cooling lines from pump to mani and then 3/8ths outa the head,if you dont run a split cooling system,keeps pressure high but doesnt over cool cylinder,otherwise just run 1/2 inch straight to the head pipe from the pump
One of the days we were tuning the true performance 965,on a newly ceramic coated headpipe,I found out some retard threw in the tumbler and got polishing balls all inside the water jacket....after riding a few min on couple b pipe water screw settings,all the sudden the power came on MUCH better for low end and responce.I noticed I had lost cooling to the top pisser,the one coming off the y split to jetworks valve. took it in and found that a bead had gotten stuck in the top cooling line and totally closed it off. This increased the pressure in the headpipe and made a huge diff. Some others there thought the diff was just cause the pipe heated up and the water box dried out. Ive found that with a jetworks valve,riding around testing low end response and power,they dont open much at all,same test nose in to dock at full throttle blips with jetworks valve disconnected from stinger. check when flow starts..I find a resrtictor on the jetworks valve useful as well. Ive heated the pipe up with almost completly closing all screwss and disconnected the stinger water completely to see if it makes anywhere near as much diff as more water pressure using restrictions to the head pipe outlet with the top screw open and it just doesn't even come close...some people just refuse to get it...try it for yourself.... you will lose some top end and a few rpms but your motor will come off bottom and mid HARD.The motor doesnt stay on the pipe up top,thusly if you or someone else rides your ski and wrings its neck wide open,the motor makes WAY less heat and is way less likely to seize with this kinda pipe setting...win win in my book if you could care less about a few mph on top end racing.
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