Enen
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Well that just got interesting... LOL How fast do you really need to go in this thing Aaron?
RD
No comprendo? :headscratch:
Well that just got interesting... LOL How fast do you really need to go in this thing Aaron?
RD
No comprendo? :headscratch:
I'll break it down for you
The boat was already stupid fast when you had just 800hp and one blower per side. Chances are you now have 1200ish hp and 2 blowers per side so how much faster do you really need to go when the boat was already stupid fast with 800 less hp?:eek:cool
That's a damn good problem to have. What man in their right mind would make such a statement [emoji2]
I'll break it down for you
The boat was already stupid fast when you had just 800hp and one blower per side. Chances are you now have 1200ish hp and 2 blowers per side so how much faster do you really need to go when the boat was already stupid fast with 800 less hp?:eek:cool
I'll break it down for you
The boat was already stupid fast when you had just 800hp and one blower per side. Chances are you now have 1200ish hp and 2 blowers per side so how much faster do you really need to go when the boat was already stupid fast with 800 less hp?:eek:cool
That's a damn good problem to have. What man in their right mind would make such a statement [emoji2]
Are those BoostPower deals?
Better to have it and not need it than need it and not have it...come on man
lol- We'll see where these end up power wise when we dyno them. I've always been more of a " walk softly and carry a big stick" kinda guy.
I agree...I would love your hallet motor under the hatch of my 210.
Just in case I have to avoid a jet ski or something...lol
I have seen them...it would look great under your hatch...not that what you have doesn't look great and I'm pretty sure you don't have any issues avoiding them now...lol
its a disease.....Boat doesn't really need to be any faster but 100+ would be fun and a pretty big surprise with stock hatch and swim step.
Do I see another snow ball coming...lol
nope...done
Was considering EFI and some head work but 8K for 3 mph just doesn't seem worth it with how the boat already runs.
Shit with the kids soccer program I haven't been out since labor day and I don't see that changing until thanksgiving.
Way to go Aaron, the family will be happy to get back to boating, hope you give me a ride.
Good to see some progress. My boat is in there at octane too. 28 Daytona. When do you think you will have this thing on the water again?
Not yet, but they will be. :thumbsup
Backstory on these engines. They were built for a guy in New Orleans, to go into a 50ft Nor Tech cat. They were assembled with the best parts by Percision Marine, and never run. They have 0 hours on them. The guy sold the Nor Tech, then offered the engines for sale. They are 598 cu with top shelf parts, painted to match my boat perfectly, and ultimately the deal of a lifetime. Unfortunately I didn't get spec sheets with the engines.
We are going to ship them to Alexi. The plan is going to disassemble them, check and measure everything internally, remove the dry sump oil system and convert it to wet sump ( no room in my bilge for dry sump) put all the accessories on the engines, modify the blowers, machine whatever is needed , dyno them and get them ready to drop in and run.
Things in motion want to stay in motion. Things that are accelerating do not want to keep accelerating though. If they kill the spark at an rpm then that's it no matter how fast it got there..
RD is right.
If electronics cut fuel, then the flywheel won't accelerate to any speed greater than where it's at.
The flywheel's energy is kinetic, due to its rotational motion alone. It's not possible to have more stored energy lurking within it.
It's like a bullet leaving a barrel. The moment the gas pushing on it is gone, it decelerates - it doesn't keep accelerating.
Let's put aside the words acceleration and deceleration.
Is it your view from above that the instant that the fuel and timing is cut, RPM can not continue to rise?
Both the computer and MSD were set up to limit the RPM. Maybe something was faulty, I dunno, but it that is how it was set.
What did you do with your old motors?
I guess i never saw this thread when it came around the first time.
Correct, just like the instant a baseball leaves the pitchers hand it begins decellerating
Aside from a firing event that is already under way that is correct, this is where having more than 1 trigger tooth per cylinder is helpful, aka crankshaft speed sensor revolution, The computer can only measure the accelleration rate and speed of the crank based on the time differential between trigger signals. If the trigger signal was coming from the distributor that is only 90 degrees of revolution between events, depending on how the distro is phased, and the instant where the load is lost, you could have the possibility of getting one additional firing event. But the instant the firing events go away the instant instant the system begins to slow down. Flywheels can't create and a release additional energy, They can only store kinetic energy, as soon as input energy is gone the system begins to decel.
We like running a 12 tooth wheel on the crank for most things (that's 30 degrees of resolution), that is 2 additional speed sensing points between cylinder events than what you get with a 4 tooth crank sensor (msd style) or a regular distributor which is that plus any degrees of slop in the distributor itself, the distro gear, and the timing set, which is measured in full degrees, not tenths, as there is quite a disconnect between the crank itself and the trigger. This is why a crank mounted sensor is superior.
58x or 60-2 like used on LS is even better depending on the box it's paired with,as that is 6 degrees between teeth (some discard additional teeth, others will do some advance trending of teeth due to slight deviations in mfg, if you have a tooth that is a few thousands off you don't want it causing a problematic deviation, and the wheels are not made with thousandths accuracy, but that is an entirely different discussion).
I actually built a machine that i can use to test the sensors and target wheels that i make for engines up to 15k rpm, and how gap adjustments to the sensor affect timing. We can reference a wheel down to 1/20th a degree of accuracy (way more than you need for a timing event in an internal combustion engine)
I'm surprised this hasn't been brought up, but it's very important to understand. You should never have the EFI computer control the spark of a the rev limiter when connected to and MSD!!!
MSD stands for Multi Spark Discharge, this is where MSD got it's foothold in the market, below 3,000RPM the coil fires MULTIPLE TIMES on every cylinder.
The MSD box is not smart, it gets a firing pulse and it fires the coil, if it is less than 3,000 rpm it will multi strike (a feature designed to keep the cylinders clean of low rpm misfire and unburned fuel fouling).
If you have the rev limiter turned on inside the EFI computer and set to cut spark, what does it do? it starts semi randomly dropping cylinder signals that it sends to the MSD box, all of a sudden the MSD box that was getting firing signals at a rate of 6,000 rpm, all of a sudden drops to below 3,000 as the rev limiter kicks in, and the MSD box goes "Oh hey, i'm back running low speed, let's multi strike." Except the motor is actually running 6,000 rpm, and the rotor is spinning to the next cylinder on the 2nd and 3rd strikes, and all of a sudden the following cylinder gets a spark event that is WAYYYYYYYYYYY advanced, like 60 degrees of timing. BNAG!!!!!!
I guess i never saw this thread when it came around the first time.
Correct, just like the instant a baseball leaves the pitchers hand it begins decellerating
Aside from a firing event that is already under way that is correct, this is where having more than 1 trigger tooth per cylinder is helpful, aka crankshaft speed sensor revolution, The computer can only measure the accelleration rate and speed of the crank based on the time differential between trigger signals. If the trigger signal was coming from the distributor that is only 90 degrees of revolution between events, depending on how the distro is phased, and the instant where the load is lost, you could have the possibility of getting one additional firing event. But the instant the firing events go away the instant instant the system begins to slow down. Flywheels can't create and a release additional energy, They can only store kinetic energy, as soon as input energy is gone the system begins to decel.
We like running a 12 tooth wheel on the crank for most things (that's 30 degrees of resolution), that is 2 additional speed sensing points between cylinder events than what you get with a 4 tooth crank sensor (msd style) or a regular distributor which is that plus any degrees of slop in the distributor itself, the distro gear, and the timing set, which is measured in full degrees, not tenths, as there is quite a disconnect between the crank itself and the trigger. This is why a crank mounted sensor is superior.
58x or 60-2 like used on LS is even better depending on the box it's paired with,as that is 6 degrees between teeth (some discard additional teeth, others will do some advance trending of teeth due to slight deviations in mfg, if you have a tooth that is a few thousands off you don't want it causing a problematic deviation, and the wheels are not made with thousandths accuracy, but that is an entirely different discussion).
I actually built a machine that i can use to test the sensors and target wheels that i make for engines up to 15k rpm, and how gap adjustments to the sensor affect timing. We can reference a wheel down to 1/20th a degree of accuracy (way more than you need for a timing event in an internal combustion engine)
I'm surprised this hasn't been brought up, but it's very important to understand. You should never have the EFI computer control the spark of a the rev limiter when connected to and MSD!!!
MSD stands for Multi Spark Discharge, this is where MSD got it's foothold in the market, below 3,000RPM the coil fires MULTIPLE TIMES on every cylinder.
The MSD box is not smart, it gets a firing pulse and it fires the coil, if it is less than 3,000 rpm it will multi strike (a feature designed to keep the cylinders clean of low rpm misfire and unburned fuel fouling).
If you have the rev limiter turned on inside the EFI computer and set to cut spark, what does it do? it starts semi randomly dropping cylinder signals that it sends to the MSD box, all of a sudden the MSD box that was getting firing signals at a rate of 6,000 rpm, all of a sudden drops to below 3,000 as the rev limiter kicks in, and the MSD box goes "Oh hey, i'm back running low speed, let's multi strike." Except the motor is actually running 6,000 rpm, and the rotor is spinning to the next cylinder on the 2nd and 3rd strikes, and all of a sudden the following cylinder gets a spark event that is WAYYYYYYYYYYY advanced, like 60 degrees of timing. BNAG!!!!!!
I guess i never saw this thread when it came around the first time.
Correct, just like the instant a baseball leaves the pitchers hand it begins decellerating
Aside from a firing event that is already under way that is correct, this is where having more than 1 trigger tooth per cylinder is helpful, aka crankshaft speed sensor revolution, The computer can only measure the accelleration rate and speed of the crank based on the time differential between trigger signals. If the trigger signal was coming from the distributor that is only 90 degrees of revolution between events, depending on how the distro is phased, and the instant where the load is lost, you could have the possibility of getting one additional firing event. But the instant the firing events go away the instant instant the system begins to slow down. Flywheels can't create and a release additional energy, They can only store kinetic energy, as soon as input energy is gone the system begins to decel.
We like running a 12 tooth wheel on the crank for most things (that's 30 degrees of resolution), that is 2 additional speed sensing points between cylinder events than what you get with a 4 tooth crank sensor (msd style) or a regular distributor which is that plus any degrees of slop in the distributor itself, the distro gear, and the timing set, which is measured in full degrees, not tenths, as there is quite a disconnect between the crank itself and the trigger. This is why a crank mounted sensor is superior.
58x or 60-2 like used on LS is even better depending on the box it's paired with,as that is 6 degrees between teeth (some discard additional teeth, others will do some advance trending of teeth due to slight deviations in mfg, if you have a tooth that is a few thousands off you don't want it causing a problematic deviation, and the wheels are not made with thousandths accuracy, but that is an entirely different discussion).
I actually built a machine that i can use to test the sensors and target wheels that i make for engines up to 15k rpm, and how gap adjustments to the sensor affect timing. We can reference a wheel down to 1/20th a degree of accuracy (way more than you need for a timing event in an internal combustion engine)
I'm surprised this hasn't been brought up, but it's very important to understand. You should never have the EFI computer control the spark of a the rev limiter when connected to and MSD!!!
MSD stands for Multi Spark Discharge, this is where MSD got it's foothold in the market, below 3,000RPM the coil fires MULTIPLE TIMES on every cylinder.
The MSD box is not smart, it gets a firing pulse and it fires the coil, if it is less than 3,000 rpm it will multi strike (a feature designed to keep the cylinders clean of low rpm misfire and unburned fuel fouling).
If you have the rev limiter turned on inside the EFI computer and set to cut spark, what does it do? it starts semi randomly dropping cylinder signals that it sends to the MSD box, all of a sudden the MSD box that was getting firing signals at a rate of 6,000 rpm, all of a sudden drops to below 3,000 as the rev limiter kicks in, and the MSD box goes "Oh hey, i'm back running low speed, let's multi strike." Except the motor is actually running 6,000 rpm, and the rotor is spinning to the next cylinder on the 2nd and 3rd strikes, and all of a sudden the following cylinder gets a spark event that is WAYYYYYYYYYYY advanced, like 60 degrees of timing. BNAG!!!!!!
I guess i never saw this thread when it came around the first time.
Correct, just like the instant a baseball leaves the pitchers hand it begins decellerating
Aside from a firing event that is already under way that is correct, this is where having more than 1 trigger tooth per cylinder is helpful, aka crankshaft speed sensor revolution, The computer can only measure the accelleration rate and speed of the crank based on the time differential between trigger signals. If the trigger signal was coming from the distributor that is only 90 degrees of revolution between events, depending on how the distro is phased, and the instant where the load is lost, you could have the possibility of getting one additional firing event. But the instant the firing events go away the instant instant the system begins to slow down. Flywheels can't create and a release additional energy, They can only store kinetic energy, as soon as input energy is gone the system begins to decel.
We like running a 12 tooth wheel on the crank for most things (that's 30 degrees of resolution), that is 2 additional speed sensing points between cylinder events than what you get with a 4 tooth crank sensor (msd style) or a regular distributor which is that plus any degrees of slop in the distributor itself, the distro gear, and the timing set, which is measured in full degrees, not tenths, as there is quite a disconnect between the crank itself and the trigger. This is why a crank mounted sensor is superior.
58x or 60-2 like used on LS is even better depending on the box it's paired with,as that is 6 degrees between teeth (some discard additional teeth, others will do some advance trending of teeth due to slight deviations in mfg, if you have a tooth that is a few thousands off you don't want it causing a problematic deviation, and the wheels are not made with thousandths accuracy, but that is an entirely different discussion).
I actually built a machine that i can use to test the sensors and target wheels that i make for engines up to 15k rpm, and how gap adjustments to the sensor affect timing. We can reference a wheel down to 1/20th a degree of accuracy (way more than you need for a timing event in an internal combustion engine)
I'm surprised this hasn't been brought up, but it's very important to understand. You should never have the EFI computer control the spark of a the rev limiter when connected to and MSD!!!
MSD stands for Multi Spark Discharge, this is where MSD got it's foothold in the market, below 3,000RPM the coil fires MULTIPLE TIMES on every cylinder.
The MSD box is not smart, it gets a firing pulse and it fires the coil, if it is less than 3,000 rpm it will multi strike (a feature designed to keep the cylinders clean of low rpm misfire and unburned fuel fouling).
If you have the rev limiter turned on inside the EFI computer and set to cut spark, what does it do? it starts semi randomly dropping cylinder signals that it sends to the MSD box, all of a sudden the MSD box that was getting firing signals at a rate of 6,000 rpm, all of a sudden drops to below 3,000 as the rev limiter kicks in, and the MSD box goes "Oh hey, i'm back running low speed, let's multi strike." Except the motor is actually running 6,000 rpm, and the rotor is spinning to the next cylinder on the 2nd and 3rd strikes, and all of a sudden the following cylinder gets a spark event that is WAYYYYYYYYYYY advanced, like 60 degrees of timing. BNAG!!!!!!
His MSD and his efi are set. The fact is under load no matter what the rev control it's hard to prevent overshooting the safe rpm from an immediate rpm spike. Especially if 6000 rpm is your limit and your mechanical limit is 6400. In today's technology it can be better managed but not on an older system [emoji1303]
Multi coil, higher res trigger mounted directly on the crank, and modern EFI not 20 year old MEFI :thumbsup:thumbsup:thumbsup:thumbsup
Any updates??
Where are the quad motors going? Aren't you getting them to check out? The boat is gonna be badass. [emoji106]
Stopped by Octane Marine today at lunch. Charlie and Sonny are getting her torn down!! Going to completely de-rig the bilge, then it's going to Nordic to flow coat the bilge.
View attachment 518519 View attachment 518518
Not yet, but they will be. :thumbsup
Backstory on these engines. They were built for a guy in New Orleans, to go into a 50ft Nor Tech cat. They were assembled with the best parts by Percision Marine, and never run. They have 0 hours on them. The guy sold the Nor Tech, then offered the engines for sale. They are 598 cu with top shelf parts, painted to match my boat perfectly, and ultimately the deal of a lifetime. Unfortunately I didn't get spec sheets with the engines.
We are going to ship them to Alexi. The plan is going to disassemble them, check and measure everything internally, remove the dry sump oil system and convert it to wet sump ( no room in my bilge for dry sump) put all the accessories on the engines, modify the blowers, machine whatever is needed , dyno them and get them ready to drop in and run.
And or trade them in if we decide to get extra nutty[emoji469][emoji1320]
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