Blower size?
12-10-2011 | 08:10 PM
#31
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From: yorkville,il
Mike, thanks for your input/response....I'll shoot you a PM.
MT, funny you mention that about the 14-71 vs a 10-71 for a 557cid. A friend told me the other day that a 14-71 blower creates more heat than one expects even when they're underdriven on engines my size (557cid). And he was told this "off the cuff" by a well known marine engine building crew in person. He said he doesn't know if there is any merit to he was told that day, but they had nothing to gain by telling him that. Then you tell me about the 14-71 blower possibly being to large for my 557's and the app I am looking for. I guess I'll have to ask Dave W...my builder.
Of course, from what I have known in the past about roots blowers is that a larger blower doesn't neccessarily give an engine more power over a smaller blower, but that it will create LESS HEAT/HEAT SOAK.
I didn't know a larger blower could actually hurt or create LESS power on the same engine vs a smaller blower.
I plan on cruising most of the time anyway. Perhaps I would be willing to trade my 14-71's for some smaller 10-71's.
Anyone else want to chime in on this 14-71 vs 10-71 on a mild cammed 557cid engine making peak power at 6000rpm???
MT, funny you mention that about the 14-71 vs a 10-71 for a 557cid. A friend told me the other day that a 14-71 blower creates more heat than one expects even when they're underdriven on engines my size (557cid). And he was told this "off the cuff" by a well known marine engine building crew in person. He said he doesn't know if there is any merit to he was told that day, but they had nothing to gain by telling him that. Then you tell me about the 14-71 blower possibly being to large for my 557's and the app I am looking for. I guess I'll have to ask Dave W...my builder.
Of course, from what I have known in the past about roots blowers is that a larger blower doesn't neccessarily give an engine more power over a smaller blower, but that it will create LESS HEAT/HEAT SOAK.
I didn't know a larger blower could actually hurt or create LESS power on the same engine vs a smaller blower.
I plan on cruising most of the time anyway. Perhaps I would be willing to trade my 14-71's for some smaller 10-71's.
Anyone else want to chime in on this 14-71 vs 10-71 on a mild cammed 557cid engine making peak power at 6000rpm???
12-10-2011 | 08:18 PM
#32
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From: yorkville,il
12-11-2011 | 05:04 PM
#33
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From: Western Michigan
Had a little chat with my engine builder today about the blower apps, etc.
I aquired these 14-71's a few years ago---but not thru my builder.
In a nutshell, he told me that if he thought the 14-71's would not work on 557's that he would have said something to me a long time ago. I told him some of things I was hearing/reading and he just quietly shook his head and looked at me and said point blank--- "Mark, it's no problem---they will work on 557's."
I don't know what he does to them if anything as he said he has to check "something" on them,---but Dave is not the type of guy who wears his knowledge out on his sleeve and I didn't pry too much. Someone else or some other builder might think Dave is feeding me a line of BS, but I DO know he is one extremely intelligent and successful dude and I trust him.
Finally, he told me that if he wanted to be dishonest or if he was ignorant with the subject he would have convinced me to trade them with him for some 10-71's he has sitting on the shelf. Then he said to me; "I'll still take your 14-71's in on trade for some 10-71's if you want---I wouldn't if I were you, but if you really want to I will"
I aquired these 14-71's a few years ago---but not thru my builder.
In a nutshell, he told me that if he thought the 14-71's would not work on 557's that he would have said something to me a long time ago. I told him some of things I was hearing/reading and he just quietly shook his head and looked at me and said point blank--- "Mark, it's no problem---they will work on 557's."
I don't know what he does to them if anything as he said he has to check "something" on them,---but Dave is not the type of guy who wears his knowledge out on his sleeve and I didn't pry too much. Someone else or some other builder might think Dave is feeding me a line of BS, but I DO know he is one extremely intelligent and successful dude and I trust him.
Finally, he told me that if he wanted to be dishonest or if he was ignorant with the subject he would have convinced me to trade them with him for some 10-71's he has sitting on the shelf. Then he said to me; "I'll still take your 14-71's in on trade for some 10-71's if you want---I wouldn't if I were you, but if you really want to I will"
12-11-2011 | 11:23 PM
#34
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From: Western Michigan
By the way, I am thankful and greatly appreciate everyone's input...I am not here to discredit anyone. I would not have known to ask had it not been for some of you guys bringing up the subject to begin with.
Besides, I really enjoy discussing all of this stuff---it is all very interesting to me and I am learning more about this blower stuff as I have always been a NA man in the past.
However, if I have to take anyone's words to bed with me, then it should probably be the words of my builder.
Anyway, Bob Madara is doing the cam profiles, JimV did the full port work on the heads, and Dave Wesseldyk is doing the machine work, balancing, assembly and dyno testing.
If the 14-71's don't work as efficiently as expected, etc, then I will let ya'll know. I am always learning---that's what makes it all fun and interesting to me.
At least, that's how I try to look at the whole thing---not trying to set any world records. I'm no expert on this stuff....just a weekend warrior that kills bugs for a living.
Besides, I really enjoy discussing all of this stuff---it is all very interesting to me and I am learning more about this blower stuff as I have always been a NA man in the past.
However, if I have to take anyone's words to bed with me, then it should probably be the words of my builder.
Anyway, Bob Madara is doing the cam profiles, JimV did the full port work on the heads, and Dave Wesseldyk is doing the machine work, balancing, assembly and dyno testing.
If the 14-71's don't work as efficiently as expected, etc, then I will let ya'll know. I am always learning---that's what makes it all fun and interesting to me.
At least, that's how I try to look at the whole thing---not trying to set any world records. I'm no expert on this stuff....just a weekend warrior that kills bugs for a living.
12-11-2011 | 11:47 PM
#35
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From: yorkville,il
nes.
i totally agree with your builder,14.71 will work good on a 557,buy the way,from what i have heard,dave is as sharp as they come,and honest,good luck with your engines.
Had a little chat with my engine builder today about the blower apps, etc.
I aquired these 14-71's a few years ago---but not thru my builder.
In a nutshell, he told me that if he thought the 14-71's would not work on 557's that he would have said something to me a long time ago. I told him some of things I was hearing/reading and he just quietly shook his head and looked at me and said point blank--- "Mark, it's no problem---they will work on 557's."
I don't know what he does to them if anything as he said he has to check "something" on themnew engi,---but Dave is not the type of guy who wears his knowledg te e out on his sleeve and I didn't pry too much. Someone else or some other builder might think Dave is feeding me a line of BS, but I DO know he is one extremely intelligent and successful dude and I trust him.
Finally, he told me that if he wanted to be dishonest or if he was ignorant with the subject he would have convinced me to trade them with him for some 10-71's he has sitting on the shelf. Then he said to me; "I'll still take your 14-71's in on trade for some 10-71's if you want---I wouldn't if I were you, but if you really want to I will"
I aquired these 14-71's a few years ago---but not thru my builder.
In a nutshell, he told me that if he thought the 14-71's would not work on 557's that he would have said something to me a long time ago. I told him some of things I was hearing/reading and he just quietly shook his head and looked at me and said point blank--- "Mark, it's no problem---they will work on 557's."
I don't know what he does to them if anything as he said he has to check "something" on themnew engi,---but Dave is not the type of guy who wears his knowledg te e out on his sleeve and I didn't pry too much. Someone else or some other builder might think Dave is feeding me a line of BS, but I DO know he is one extremely intelligent and successful dude and I trust him.
Finally, he told me that if he wanted to be dishonest or if he was ignorant with the subject he would have convinced me to trade them with him for some 10-71's he has sitting on the shelf. Then he said to me; "I'll still take your 14-71's in on trade for some 10-71's if you want---I wouldn't if I were you, but if you really want to I will"
12-12-2011 | 09:33 AM
#36
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From: chicago
Hey Mark, No worries man! If anyone would know the answers to these questions its definitly Dave W.
Sounds like you are on the right path, a cylinder head guru doing your heads, a cam specialist doing your cams, and engine master doing your machine and assembly. Sounds like a winning combination there!!
Sounds like you are on the right path, a cylinder head guru doing your heads, a cam specialist doing your cams, and engine master doing your machine and assembly. Sounds like a winning combination there!!
12-12-2011 | 11:54 AM
#37
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From: Aurora Ontario
As another option, I did a 8.0 to 1 540 for a buddy this past summer. AFR 357 heads out of the box, crane 268741 hydraulic roller, morel,jessel etc and a 4.0 whipple. It made 1102 at 6000 and over 1000lbf.
Starts and idles smooth as silk, no surge, no anything really except smooth, solid power.
12-12-2011 | 01:19 PM
#38
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From: Lake Michigan
No reason to go any larger than 8-71's on a 509. Innercooling not necessary. Never mentioned was the the driveline, what drives are on this boat?
With todays fuel diluted with ethanol i wouldnt go past 32* and dual 750 carbs are plenty big.
With todays fuel diluted with ethanol i wouldnt go past 32* and dual 750 carbs are plenty big.
12-12-2011 | 01:54 PM
#39
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From: Cedar Springs MI
Huber 1350 transmissions, and big shaft #4's. Can I turn up the boost enough to make 850 with iron heads and no chiller though? It is sounding like I need to either run aluminum heads or run the chillers to get the boost high enough to get the HP results I am seeking?
12-12-2011 | 03:46 PM
#40
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From: Western Michigan
Rov V, man I am sorry for "hi-jacking" your thread---I truely appologize. It is very easy to get caught up in the back and forth banter of questions and responses, but I think it has been a very helpful "blower" thread to most of us who are students......like me. 
