I was looking at some parts for my berk. pump and saw different numbers of vains in the bowls, what is the purpouse of this and when would it be of an advantage to use one of these???
IMHO, unless it's a race boat spinning higher than 6500 RPM, you won't gain much converting from a regular 8 vane. When you dump it wide open, what kind of RPM are you turning?I was guessing that it would effect the efficiency of the pump, I'm looking to make my pump work with the motor that I've got, (to the best of its ability) I'd like to see some gain for the amount of money and time I have already put in. Im willing to try any thing once with in reason!!
68 @ 4900 is pretty decent actually. Without a shoe or a ride plate my boat's doin' 77 @ 5300 so your numbers are close.my current top speed is 68.5 ALL DAY LONG i have hit 73 on choppy water once and 70 in chop other times. Im trying for the 70 mark constant any thing more would be great. No way will i run a chevy thats to easy. Gota beat my self up a little with the olds slowness. It dose matter for lake boats if you are never satisfied and are constantly looking to improve. however it maybe a foolish task. I'll still try if fesable to see a gain.
You are correct in that pumps act like a high stall converter. However, jet boats and cars are two different things.Understood that the bowls are for higher hp. But like in a torque converter if you change the pitch or number of the fins on the stator or the impeler it has an effect on the stall speed(slipage) hence, my thoughts of this being true in a jet pump would be the same. If you change the stall speed on a car it can make all the difrence in the world on how it preforms, understood also that the imp is probably the easiest and most efective way to see this gain even at a low hp it would have an effect switch to a 7 vane and it could cause a positive gain.
I see what you're saying. What I'm trying to say is that an impeller change would benefit you more than a bowl change. The impeller cut governs how much of a load the motor sees at a given RPM (by how much water it moves per RPM)...not the type of bowl you run. So to allow the engine to increase RPM you would use an impeller with a smaller cut. Plus an impeller is much cheaper than a bowl.I cant agree with you more in your complet statement in comparing the boat to a car siting still, it's like letting go of the line lock button or letting off of the break pedal if you are a foot brake racer like I was.
You said "The water flowing through the pump is what provides the load." If you change one part of the equation i.e. the bowl or the imp.the load has to change there for the eficiency must also change. Wether it would change for the better is my question. As you know building power in an olds =$$$$. Ive already done the motor to a sutabile unit for perf./durability it is a solid unit. That is why Im looking at improving the efficiency of the pump to its fullest for the motor. Just cuz I spend all the money in the world on a pump that is desighned for a high HP/rpm boat dosent mean that it is what will work for me. Im sure that you will also agree with me on this.
So I guess what im looking for is are there other pump combos that other people have tried that may show me gains. A good performing pump built to my motor is cheaper and more efective than building more HP with the olds.
I want the total packege as efficient as I can get it. efficency=speed. Lets face it this boat will never be a rocketship.