What props and what hp??
07-11-2003 | 06:44 PM
#11
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Joined: Nov 2002
Posts: 532
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From: CT
OK, finally talked to hydromotive today. (Tod)
With my 90 251 convincor, (425hp, 502) he suggest that I start with a 25p QIV. He actually said a 24" first but did some research on past "same" boats and said that what i should do is go with the 25", run it, get back to him with the numbers and he would lab it and bring the diameter down to pick up the rpm to about 5100-5200@ wot.
I'll post what i come up with. Will have the stock 25" next week.
Great guy to deal with and I like there policies on returns and exchanges.
With my 90 251 convincor, (425hp, 502) he suggest that I start with a 25p QIV. He actually said a 24" first but did some research on past "same" boats and said that what i should do is go with the 25", run it, get back to him with the numbers and he would lab it and bring the diameter down to pick up the rpm to about 5100-5200@ wot.
I'll post what i come up with. Will have the stock 25" next week.
Great guy to deal with and I like there policies on returns and exchanges.
07-15-2003 | 06:35 AM
#12
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Joined: Jun 2003
Posts: 40
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From: Grand Rapids MI
Liquidator
For the question about compression I'm sorry I did not add somthing. The motor has ALL NEW STUFF in it. Pistons as well, so I hope the compression will be OK for a long time. The motor was machined and balanced as well. We spent alot of money on this boat in the last year so it better work, better than it did before. It has to, before it had 365hp and now it has about 440hp at the dyno. So we now that part of it works. I think the problem is in the boat mainly the drive height. The boat will not cruse very well at all. This thing is out of the water more than it is in. When I put the hammer down it runs fine. Anything over 50mph the boat runs on the pad just the way it's designed to. The three blade props are the fastest I hear but I would like the best of both worlds fast and safe. The boat does tend to chine walk at top end. Can make my wife and kids yell at me to slow down.
For the question about compression I'm sorry I did not add somthing. The motor has ALL NEW STUFF in it. Pistons as well, so I hope the compression will be OK for a long time. The motor was machined and balanced as well. We spent alot of money on this boat in the last year so it better work, better than it did before. It has to, before it had 365hp and now it has about 440hp at the dyno. So we now that part of it works. I think the problem is in the boat mainly the drive height. The boat will not cruse very well at all. This thing is out of the water more than it is in. When I put the hammer down it runs fine. Anything over 50mph the boat runs on the pad just the way it's designed to. The three blade props are the fastest I hear but I would like the best of both worlds fast and safe. The boat does tend to chine walk at top end. Can make my wife and kids yell at me to slow down.
07-15-2003 | 08:38 AM
#13
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Joined: May 2001
Posts: 357
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From: St. Joseph, MI
I run an 86' 251 as well. The Mirage three blade runs the best for top speed but it chine walked real bad. I added Full Hydrualic steering (twin ram Imco) and relocated the trim tabs (Bennet 12x16) inboard as far as possible. This has helped reduce the chine walk problem, then I tryed a 4 blade hydromotive, while I have increased my plane time and reduced my top speed, it has INCREASED my cruise speed, I now cruise at 65mph @ 4500 rpms with a rock solid ride. I think my next move is to try a Imco 2" shortie, I feel that will put me in the mid 80's but I am afraid my chine walk will then return. If so K planes will be next.
07-15-2003 | 05:31 PM
#14
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Joined: Jun 2003
Posts: 40
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From: Grand Rapids MI
dlbcheckmate
I have thought about full hydrualic steering as well. I also thought aout a stand off box too. But not now no more money this year. I know some one at the shop Valako's I mean. That has one it came off a 26 checkmate one of the ZT I think. He saw some good speed out of it. He has the boat for sale at Premier Motor Sports in Gun Lake if anyone knows someone that needs a good used boat. So he doesn't need it anymore. That was the 26 lab bravo one I used. It is for sale also. But back to our boats mid 80's thats fast. How much hp does that take. A good friend had our same boat and had 740hp out of a 540. He used a 3-blade mirage lab 25 with cup added. Same problem chin walk a top end. But that boat is sold too. But with a stock 454 365hp.
I have thought about full hydrualic steering as well. I also thought aout a stand off box too. But not now no more money this year. I know some one at the shop Valako's I mean. That has one it came off a 26 checkmate one of the ZT I think. He saw some good speed out of it. He has the boat for sale at Premier Motor Sports in Gun Lake if anyone knows someone that needs a good used boat. So he doesn't need it anymore. That was the 26 lab bravo one I used. It is for sale also. But back to our boats mid 80's thats fast. How much hp does that take. A good friend had our same boat and had 740hp out of a 540. He used a 3-blade mirage lab 25 with cup added. Same problem chin walk a top end. But that boat is sold too. But with a stock 454 365hp.
07-15-2003 | 08:35 PM
#15
I hate the winter!!
Joined: Jul 2001
Posts: 2,707
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From: long island, new york
I am currently running a labbed 26 Bravo in my '99 Convincor with a mostly stock 454 magnum. I can turn it to 4950 r.p.m., shows 75 speedo. ( I know it isn't going that fast ) I switched from a stock 24" Bravo, lost 50 r.p.m. but picked up a solid 3 m.p.h. I also added Imcos' dual ram full hydraulic steering. It made a big difference at speed. It is rock steady! No more slop in the wheel.
07-21-2003 | 01:55 PM
#18
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Posts: 357
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From: St. Joseph, MI
ATU, I bought Todds 468 he sold before he built his 540. I will be rebuilding at the end of this year, I would like to get a new short block (509) and reuse my top end (Valako wedge heads) but I will need to put seats in the heads, so I may get new Dart pro1's form Valako ? His motors make some power thats for sure.
07-22-2003 | 05:57 AM
#19
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Joined: Jun 2003
Posts: 40
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From: Grand Rapids MI
dlb
Jim and BJ will help you when the time comes. They are helping me with mine right now. Are you going to use your other parts from the 468 or are you going the sell it complete. If I remember right that motor had all the good stuff on it. Dart intake with a big carb and dart heads and a huge cam. Still running good. His brother can build a great motor. His new boat is very fast over 90 in a 283 convincor. He helped me design my motor. But Jim and BJ built it. Steve did not have the time. He was working on his boat.
Jim and BJ will help you when the time comes. They are helping me with mine right now. Are you going to use your other parts from the 468 or are you going the sell it complete. If I remember right that motor had all the good stuff on it. Dart intake with a big carb and dart heads and a huge cam. Still running good. His brother can build a great motor. His new boat is very fast over 90 in a 283 convincor. He helped me design my motor. But Jim and BJ built it. Steve did not have the time. He was working on his boat.
07-22-2003 | 06:21 AM
#20
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Joined: Jun 2003
Posts: 40
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From: Grand Rapids MI
dlb
I just thought of some thing. Mr. Gadgets has a 509 in the corner of his garage under plastic. It was in his old 251 that looked like Todd's. See if he will part with it.
What do you think Gadgets.
Post sometime.
I just thought of some thing. Mr. Gadgets has a 509 in the corner of his garage under plastic. It was in his old 251 that looked like Todd's. See if he will part with it.
What do you think Gadgets.
Post sometime.
