How much fasted should 75hp make it go?
05-20-2005 | 04:02 PM
#21
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From: Cape Coral, Florida
Re: How much fasted should 75hp make it go?
Originally Posted by FX10
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Happily retired and living in Heavens waiting room.
05-20-2005 | 04:04 PM
#22
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From: Michigan
Re: How much fasted should 75hp make it go?
Originally Posted by FX10
Ron,
I totally agree. Even at this point 85 sounds good. I was readind an article in a Feb. issue of Powerboating mag. The article was on a Formula 380 Fastec hull, which formerly had 575's (not 525's) in it. It was rigged with the new 600 Merc's, and claimed a gain of between 4-6 mph. And that was with only 50 more hp. Does that sound right to you. I was going to bring the article home and scan it, then put it online here. Maybe Monday I'll do it.
Rick
I totally agree. Even at this point 85 sounds good. I was readind an article in a Feb. issue of Powerboating mag. The article was on a Formula 380 Fastec hull, which formerly had 575's (not 525's) in it. It was rigged with the new 600 Merc's, and claimed a gain of between 4-6 mph. And that was with only 50 more hp. Does that sound right to you. I was going to bring the article home and scan it, then put it online here. Maybe Monday I'll do it.
Rick
Like I said, it depends on your starting point. If you have a 2500lb boat with 200 hp and you go to 275 hp you're gonna get a hell of a lot more than if you start with a 5000lb boat with 700 hp and go to 775 hp.
05-20-2005 | 04:10 PM
#23
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From: IL...XLOTO
Re: How much fasted should 75hp make it go?
Originally Posted by FX10
Ron,
I totally agree. Even at this point 85 sounds good. I was readind an article in a Feb. issue of Powerboating mag. The article was on a Formula 380 Fastec hull, which formerly had 575's (not 525's) in it. It was rigged with the new 600 Merc's, and claimed a gain of between 4-6 mph. And that was with only 50 more hp. Does that sound right to you. I was going to bring the article home and scan it, then put it online here. Maybe Monday I'll do it.
Rick
I totally agree. Even at this point 85 sounds good. I was readind an article in a Feb. issue of Powerboating mag. The article was on a Formula 380 Fastec hull, which formerly had 575's (not 525's) in it. It was rigged with the new 600 Merc's, and claimed a gain of between 4-6 mph. And that was with only 50 more hp. Does that sound right to you. I was going to bring the article home and scan it, then put it online here. Maybe Monday I'll do it.
Rick
Let's see, that isn't $1000 for mph, more like over $10,000 per mph. Ouch
05-20-2005 | 06:47 PM
#24
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From: Emerald Isle, North Carolina
Re: How much fasted should 75hp make it go?
That Fastec Formula claimed a top speed of 83 !!! LOL
Anyway, if Merc hopes to sell these extremely expensive 600's that are only going to give you a mile or two an hour, they better think about upping the rev limiter to around 5600-5700 rpm, and turning the boost up alittle more then 6 lbs. You should see AT LEAST 4-5 mph. to justify spending that kind of money
Anyway, if Merc hopes to sell these extremely expensive 600's that are only going to give you a mile or two an hour, they better think about upping the rev limiter to around 5600-5700 rpm, and turning the boost up alittle more then 6 lbs. You should see AT LEAST 4-5 mph. to justify spending that kind of money
05-20-2005 | 09:42 PM
#26
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From: CT
Re: How much fasted should 75hp make it go?
This discussion comes at a very opportune time for me as well. Im ready to decide on the 525 or the 600SCi and quite frankly what Im hearings is forget the 600. It is a huge step for me to take $$$ wise to go with the 600 and there is certainly the WOW factor when you lift the hatch but WHERES THE BEEF!!!
05-20-2005 | 10:34 PM
#27
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Re: How much fasted should 75hp make it go?
Originally Posted by OH-ZONE
This discussion comes at a very opportune time for me as well. Im ready to decide on the 525 or the 600SCi and quite frankly what Im hearings is forget the 600. It is a huge step for me to take $$$ wise to go with the 600 and there is certainly the WOW factor when you lift the hatch but WHERES THE BEEF!!!
05-21-2005 | 08:28 AM
#29
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From: Emerald Isle, North Carolina
Re: How much fasted should 75hp make it go?
Another link to get the most out of a motor. Gear ratios and props.
http://www.go-fast.com/Prop_Slip_Calculator.htm
http://www.go-fast.com/Prop_Slip_Calculator.htm
05-21-2005 | 09:50 AM
#30
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From: Vestal/Binghamton NY
Re: How much fasted should 75hp make it go?
Originally Posted by craig223
That's incredible how accurate that is!!
Craig is right on the money there.
I had a 350 carbed mag 270hp alpha on my boat 53mph gps
swapped it out with a 502 efi 415hp bravo
Gsp speeds of 71 was my Max
