Hard on the Drives???
02-12-2014 | 12:58 AM
#32
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Joined: Jan 2008
Posts: 2,357
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From: San Diego
The one chic in the back looks fun. The dude drving has a wedding ring and probably doesn know what that fockin red cord is for !
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02-12-2014 | 07:10 AM
#34
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Joined: Sep 2002
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From: Frankfort, IL
Oh...it can be done. I'm sure I'm not the only guy to do it. Stock 502EFIs, popped a B1 getting on plane on a rough day on Lake Michigan. Worst part was, I was giving some college-age hotties a little thrill ride while my wife was back on the dock. Ride ended prematurely (I SWEAR, THIS NEVER HAPPENS!). Lmao.
Called my wife back at the dock and told her we were coming in on one with a big oil slick behind us...please make me a stiff drink.
Called my wife back at the dock and told her we were coming in on one with a big oil slick behind us...please make me a stiff drink.
02-12-2014 | 07:38 AM
#35
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From: Michigan
Where, what RPM, does a big block make most of it's torque? I'm not saying that it's a good idea to do what this guy did, lord knows I'm guilty of a few alcohol induced hole-shots. I'm just saying I never broke a drive WFO. I broke them bastards under 3500 rpm. I was probably a ****ty stick man, but how do you break a bravo behind stock black? Pretty f'ing hard to do.
02-12-2014 | 09:40 AM
#37
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From: Delray Beach, FL
02-12-2014 | 09:46 AM
#38
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From: Traverse City MI
I know of many boats that blow bravos x and xr behind stock 496s or just plain wear them out within a couple 100 hours. They are a junk drive doesn't matter how much you baby them they WILL break prematurely
02-12-2014 | 10:12 AM
#39
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Joined: Jun 2007
Posts: 7,311
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From: Merritt Island, FL
Idk
I have 370-380 on bravo 1's behind HP500EFI's.
No problems and just had them taken apart to check out,,,,,
Transom assemblies needed rebuilt. But my drives are deep and the boat planes pretty easy with tabs all the way down and drives tucked in.
I have 370-380 on bravo 1's behind HP500EFI's.
No problems and just had them taken apart to check out,,,,,
Transom assemblies needed rebuilt. But my drives are deep and the boat planes pretty easy with tabs all the way down and drives tucked in.
02-12-2014 | 10:21 AM
#40
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Joined: Jul 2004
Posts: 11,332
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From: chicago
While I see absolutely no good reason to do full throttle starts, what do you think they do during powerboat testing and performance reports? I'd probably rather buy a 33 Fountain with 496's that had some full throttle starts on a small lake or river, over the 33 with 496's that ran it offshore in big water like great lakes or the ocean getting it airborne every weekend.
Many times drives break not because of HP. Prop pitch, boat weight, prop style, x dimension, etc. Perfect example is the 42 Fountains with the dry sump 6 drives coupled to the 700SCI. The 700SCI isn't busting the drive. Its the high propshaft height, 6 blade props, high pitch, rough water etc. Then there are guys with dry sump 6's running a lot more hp through them on a 41 apache with no issues.
I can tell you from a friend who's developed a product, that you will see on the market very soon, the engine isn't breaking the drives in most cases. When you have torque sensors hooked to your driveshaft measuring the torque readings live and logged into a laptop, on flat ass calm water, the most the drivetrain will see is whatever the engine produces. Get into any kind of chop/rough water, even at moderate speeds, and you'll find the torque spikes on the drivetrain to be in the thousands of ft lbs.
Think of it this way. You can take a bone stock mustang and floor it from redlight to redlight without wheel spin, and the trans,rear axles will most likely take it all day long. Now, dump that clutch and let those tires break loose, spinning and smoking until they bite, and see how long before you smoke a rear end or snap an axle. Happens all the time in the big truck world. You can have a big old Kenworth with a 600 cummins in it, loaded to 80k+ lbs, and boost it up with your foot to the floor all day getting up to speed or climbing a mountain. Get that truck off the pavement in some loose gravel or mud, and get some wheel spin going while your foots on the throttle. That's when the service truck has to come out to replace a busted axle or pinion gear.
Take a slab of concrete and you can park a semi truck on it and not crack it. Smack it hard enough with a 20 lb sledge hammer and watch it crack. Concrete is strong, but brittle. Much like gears and shafts.
Many times drives break not because of HP. Prop pitch, boat weight, prop style, x dimension, etc. Perfect example is the 42 Fountains with the dry sump 6 drives coupled to the 700SCI. The 700SCI isn't busting the drive. Its the high propshaft height, 6 blade props, high pitch, rough water etc. Then there are guys with dry sump 6's running a lot more hp through them on a 41 apache with no issues.
I can tell you from a friend who's developed a product, that you will see on the market very soon, the engine isn't breaking the drives in most cases. When you have torque sensors hooked to your driveshaft measuring the torque readings live and logged into a laptop, on flat ass calm water, the most the drivetrain will see is whatever the engine produces. Get into any kind of chop/rough water, even at moderate speeds, and you'll find the torque spikes on the drivetrain to be in the thousands of ft lbs.
Think of it this way. You can take a bone stock mustang and floor it from redlight to redlight without wheel spin, and the trans,rear axles will most likely take it all day long. Now, dump that clutch and let those tires break loose, spinning and smoking until they bite, and see how long before you smoke a rear end or snap an axle. Happens all the time in the big truck world. You can have a big old Kenworth with a 600 cummins in it, loaded to 80k+ lbs, and boost it up with your foot to the floor all day getting up to speed or climbing a mountain. Get that truck off the pavement in some loose gravel or mud, and get some wheel spin going while your foots on the throttle. That's when the service truck has to come out to replace a busted axle or pinion gear.
Take a slab of concrete and you can park a semi truck on it and not crack it. Smack it hard enough with a 20 lb sledge hammer and watch it crack. Concrete is strong, but brittle. Much like gears and shafts.
