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Discussion Starter #1
Ok guys, there may already be a post on this topic and if there is, please provide the link. I have an older dominator bowl with the 5 1/4 outlet side. what would be the benefits or lack thereof from opening this thing up? I have called around, and i get the same story, that it may add 1-5 mph. However, i was talking with a friend this weekend that did this to an older berkely bowl and lost mph. I am running a dominator 12-s, DPS inducer, stainless A impeller, and droop and turning around 5600 on motor. I know i could cut the impeller down to get more RPM, but i am planning on building a bigger motor soon, and dont wanna have to buy another $1k impeller. lol I am trying to get the most out of this pump without having to buy any more hardware. Also, what could be gained from having the impeller detailed? I will post what pics i have if needed.

Thanks,
AE
 

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How qwik is this new engine coming into the fold? Are you a racer? or a wannabe like me? If you detail the Impeller it should grab more water and lower your RPM by improving the water flow. You know what trimming to smaller cut will do, well so be it. Bowl detailing is best left to the experts. I think the pumps that are set up for racers and some high end guys on the lake have matching components. The Pump experts and racers know of other ways. That is the loading of the impeller that you have with more water, Making sure that load is distributed evenly on the inlet side. Adjusting the outlet flow/ VS pressure of outlet flow,"Exit nozzle inserts". There is alot more to this stuff. Folks that know more than me can help, but you need to answer some basic questions. I will start: If you are changing engines, why mess with what you have until the new engine is in? Are you looking for a mph or a sanctioned race ET? What type of hull do you have? V-bottom, tunnel, Older sanger double concave, Gull wing, Flat bottom, Mod tunnel? Hang in there Alter Ego. DEL.
 

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Discussion Starter #3
How qwik is this new engine coming into the fold? Are you a racer? or a wannabe like me? If you detail the Impeller it should grab more water and lower your RPM by improving the water flow. You know what trimming to smaller cut will do, well so be it. Bowl detailing is best left to the experts. I think the pumps that are set up for racers and some high end guys on the lake have matching components. The Pump experts and racers know of other ways. That is the loading of the impeller that you have with more water, Making sure that load is distributed evenly on the inlet side. Adjusting the outlet flow/ VS pressure of outlet flow,"Exit nozzle inserts". There is alot more to this stuff. Folks that know more than me can help, but you need to answer some basic questions. I will start: If you are changing engines, why mess with what you have until the new engine is in? Are you looking for a mph or a sanctioned race ET? What type of hull do you have? V-bottom, tunnel, Older sanger double concave, Gull wing, Flat bottom, Mod tunnel? Hang in there Alter Ego. DEL.
Ok, to answer a few questions, i am runnin a condor TX-19 gullwing, I have a place diverter with three different inserts which will adjust the speed up and down, but not that much. I am running about 750 hp on motor, and it is built to handle around a 350 shot. I will either have a new engine, or a new boat this winter, i would hope for a new boat since the motor is still strong :D, I race the boat in the SE class, and 9 second in the 1Kft. I am simply trying to get all that i can out of my hardware that i have. If I can open the bowl and gain a couple MPH, that would save me from cutting down a $1K impeller, only to be too small later on down the road. I simply started this thread so that anyone with expereince could tell me what performance gains can be realized from having the bowl detailed and opened up.
 

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Josh i have no idea why you wont cut and detail the impeller?

there are boats with way more HP and way smaller impellers than you have running way faster.

IMO you can spend all the money you want on the bowl but each piece needs to be blueprinted together.



long story short you need to turn more RPM to make the pump work at its peak.


Travis...
 

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Discussion Starter #5
Josh i have no idea why you wont cut and detail the impeller?

there are boats with way more HP and way smaller impellers than you have running way faster.

IMO you can spend all the money you want on the bowl but each piece needs to be blueprinted together.



long story short you need to turn more RPM to make the pump work at its peak.


Travis...
It is funny you chimed in! I didnt start thinkin about this bowl thing until i saw a picture of how open your bowl was on teh exit side. Regardless of cutting the impeller, it seems that I could still benefit by opening the bowl up to match the newer style bowls such as yours. Again, i am just asking, and I do plan on sending the pump off or carrying to scotty to get done right. I am just asking the question to educate myself about cutting my bowl to match or closely match yours. I didnt want to cut the impeller just yet, b/c i dont want to lose cruising RPM, or fuel mileage, but I want to make my pump as efficient as possible with the parts i have. Just educating myself, but it seems that nobody will chime in and spread the knowledge!
 

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Ok, to answer a few questions, i am runnin a condor TX-19 gullwing, I have a place diverter with three different inserts which will adjust the speed up and down, but not that much. I am running about 750 hp on motor, and it is built to handle around a 350 shot. I will either have a new engine, or a new boat this winter, i would hope for a new boat since the motor is still strong :D, I race the boat in the SE class, and 9 second in the 1Kft. I am simply trying to get all that i can out of my hardware that i have. If I can open the bowl and gain a couple MPH, that would save me from cutting down a $1K impeller, only to be too small later on down the road. I simply started this thread so that anyone with expereince could tell me what performance gains can be realized from having the bowl detailed and opened up.
do you have a dyno sheet on that engine, so you know how much it's making? do you know peak hp rpm? with the kind of power you're talking about, you should at least be running 10s.

blueprinting a pump can result in big performance gains. but it needs to be done as a unit, not peacemeal. and it's not something that should even be considered as a diy project. if there's nothing wrong with it (no knew parts needed), and you decide to do it, take it or send it to someone that has a track record doing a couple thousand, and get it done right the first time.
 

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Discussion Starter #7
do you have a dyno sheet on that engine, so you know how much it's making? do you know peak hp rpm? with the kind of power you're talking about, you should at least be running 10s.

blueprinting a pump can result in big performance gains. but it needs to be done as a unit, not peacemeal. and it's not something that should even be considered as a diy project. if there's nothing wrong with it (no knew parts needed), and you decide to do it, take it or send it to someone that has a track record doing a couple thousand, and get it done right the first time.
I do not have not dyno'd the motor. Again, I would love to have the entire unit blueprinted, and I guess i need to wait until the off season to do so, I only started this thread to ask those who have either changed bowls, or had their 5, 1/4" bowl opened up, what their performance gains were. I understand that I could gain RPM, by cutting the impeller, and also that the whole pump needs to be done as a unit, and that i need to know exactly what HP the motor makes at what RPM. I think the boat would run in the 10's if I wanted to spray the full 350 shot every time, i am right at 11 with a 100 shot, and ran 9.003 at SITC with a 50 shot. I think this thread was mis understood, but thats ok!
 

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Exit I.D

I have inlarged the exit of the old dominators and detailed the exit to fit berkeley steering adaptors (which I belive are 5/8" larger). If you measure the hole in the steering adaptor between the two, (berk vs dom) the hole is the same size. I think that would be the choke point. Not the I.D. of the bowl on the exit. I sold the bowl before running so dont know if it helped or not. I would not do it again, or pay to have it done. But thats just me. Now the transition on the Berk is smoother, maybe thats why they say it helps. Be safe. schick PS If you are running droop your bowl will be the choke point as to a larger/berkeley style.
 

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it could be the thread was misunderstood. but it looked like you asked two or three different questons.


what could be gained from having the impeller detailed?

If I can open the bowl and gain a couple MPH, that would save me from cutting down a $1K impeller, only to be too small later on down the road.
not to repeat myself, but the entire pump should be blueprinted together at the same time by the same person. you blueprint the impeller to take advantage of the blueprinted impeller. you blueprint the bowl to take advantage of the blueprinted impeller. this should be done by a pro that has years of experience doing the same thing, to get the benefit out of doing it. 9 times out of 10, a diy'r just whittling away on stuff is going to screw it up worse than it was before. not saying you would. just saying, most of the time that's how it goes. i've taken my pump apart and put it together many times - no big deal. but if there's any changes that will affect performance, my deal comes out of the boat, goes in a box or truck and goes to mpd.

I simply started this thread so that anyone with expereince could tell me what performance gains can be realized from having the bowl detailed and opened up.
blueprinting done correctly makes the pump more efficient. it will pump more water at higher velocity, at a lower rpm. i.e., it would go quicker and faster at a lower rpm. the caveat to that is your hp curve, and how far hp would fall off from, say 5600 to 5400. that's the unkown. kind of like not knowing how much hp you would pick up from 5600 to 5800/6000.

you mention leaving the impeller an a for the new engine. what is the plan for the new engine? if you know what it is, that can help plan ahead for impeller/pump details. depending what you have planned, an a might be larger than you'll want, or it may be smaller than you'll want.
 

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Josh imo you will be wasting money by just Detailing the bowl Period!:)hand
 

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Discussion Starter #11
Alright BP, And Turd!, I appreciate the advice, i will sit on this and maybe have scotty just cut the impeller for now and see what that does. I picked up quite a few mph when we cut it from a AA to an A, and i agree, that maybe the impeller is still a lil too big for my turd motor. If money permits, I will pull the motor this winter, dyno it, and send the pump off to be worked over by someone with experience....And by the way, I had no intentions of doing this myself, i would totaly FOCK it up! Also, I am not talking about detailing the bowl, just opening it up, so that it has the same or as close to the same exit size as the newer style bowls, without having to buy a new one. Lets just let this thread die, i think I have confused you guys and possibly myself with the questions!:p
 

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Send it to me.

Well do it like this one for free and you tell us how it worked. This is a old dominator bowl opened up.

Just for fun.

AR.
 

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As per BP298, a properly matched pump can add some nice efficiency... but on the other side of the equation, an improperly modified bowl or impeller may cause you more problem than benefit.

AE you can ask Barry H. about the bowl modifications. Did you see the chromed one on the porch at the Outlaw camp this weekend. Mighty pretty, but the bowl was enlarged internally to the point where it was not properly balanced with the system and his boat slowed down. He put a near stock bowl back on the boat and regained some of his lost performance. It is a water pump with a pressure balance system.

Some basic radiusing and smoothing may help, but don't go crazy and start grinding on the fins and doing a lot of enlarging.

I have ground on a few bowls and impellers myself over the years, but when it came down to my current race boat... I too followed the recomended path of BP.
 

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Alright BP, And Turd!, I appreciate the advice, i will sit on this and maybe have scotty just cut the impeller for now and see what that does. I picked up quite a few mph when we cut it from a AA to an A, and i agree, that maybe the impeller is still a lil too big for my turd motor.
there ya go. believe it or not, i know a few guys running b/c cut impeller to spin the motor and do well over 110mph. im not saying to cut it to a b/c, but never hurts to cut down with what you have.
 

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yeah for some reason everyone things the larger impeller is the way to go?

maybe for a cruiser!

Josh don't get confused,there is some good info in this thread;)

i think you are over thinking things with the bowl idea?



i have had a bowl that someone not sure who worked over in inlet and exit side,Looked a lot like the one Ballztech posted and it slowed my Old boat down.


Cut the Impeller some TURD!!!!

if you had access to a Data AQ-you could test with or without the Inducer and tell what that things does for you?
 

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Discussion Starter #19
Here is what brought on my blunder. Notice how small the exit opening is. There is not a transition between the bowl and the droop. I figured it would be better to have a smooth transition, as opposed to having two pinch points, one being at the back of the bowl and the other at the nozzle. Look at this pic trav, then look at your bowl. I talked to scotty n I think we r gonna cut the impeller to an AB. .
 

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Trav, look at this pic, and then look at yours.Scott seems to think there should be a smooth transition between the bowl and droop, I am gonna carry it to him and let him check it out, I have to have a shoe made, and he is gonna cut the impeller.
 

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