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Originally Posted by Bawana
(Post 4272072)
Ok,I thought I would bring this back up. Its almost spring and was wondering if you guys have gone in any direction with this yet????
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Originally Posted by Young Performance
(Post 4197969)
With a carb engine, you would look like you are swinging numchucks on the throttles.
Eddie |
Originally Posted by Young Performance
(Post 4197914)
I think you are on the right track. I would be very concerned running an SC engine with locked out timing. In an efi engine (speed density, ie, MEFI), everything is based off of MAP (manifold absolute pressure) Timing is based on load. Take a supercharged efi engine making roughly 1000 hp. At 100 kpa (no vacuum, no boost), it may have 30 deg at 5000 ramping up to 35 deg at 6000 rpm. Depending on boost, it may have a small negative number to remove some timing once it is in boost. That may only be 1-3 deg. That will depend on rpm and boost. The higher the boost and lower the rpm, the more negative the number (taking out more timing) At higher rpms and lower boost levels, no timing is taken out.
Now, at a Kpa level lower than 100 ( in vacuum) the timing may be 36-40 deg. The lower the Kpa (more vacuum) the more timing it will have. So, at 5000 rpm and 80 Kpa, it may have 38 deg., at 90 Kpa it may have 35 deg and at 100 Kpa it may have 30 deg. Anything over 100 Kpa is boost. If the boost is say less than 5-6 psi, than the timing may stay at 30 deg. If boost is over 5-6 psi, you may start taking out 1-2 deg. That may also increase as boost increases. This is what really sets efi apart. There is unlimited tuning to be done to the spark curve. You can add as much as it wants when the load is light ( high vacuum) and then start taking it away as load increases. As rpm catches up, you can start putting it back in. Also, with the Mefi (not sure about others), it has what's called "idle spark stabilization". This will add or remove timing to keep a smooth idle and prevent the engine from stalling. You can program it to add as much as you want. It's not uncommom for it to add 20+ deg and raise the timing to 40deg at idle. It's really nice when you have a boat with 41" props and 1.24:1 gears. It's a tremendous amount of load when you put it in gear. The IAC will open up and the timing will come way up to keep it idling so that it may only drop 100-200 rpm from neutral. With a carb engine, you would look like you are swinging numchucks on the throttles. Of course, you also have the protection of a knock sensor. With the Mefi, you can not only control when it listens, but the sensitivity of it. You can compensate for a noisy solid valvetrain, drivetrain noises, etc. You can change the temp at which it listens if you have a worn out engine with some piston slap when it's cold......and on and on. It will do just about anything you want it if you spend the time. Hope this helped shed some light on it. I tried to simplify it as much as possible. Eddie |
I will only add that watching the spark stabilization at idle with my MEFI is truly astonishing. Within 1-3 seconds after start the IAC and ignition have the motor idle tamed nicely, in spite of the mildly aggressive cam. Watching the timing graph at idle is like watching the EKG of a heart attack patient on crack. It's all over the place, but the idle is nice. Great stuff.
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Originally Posted by MILD THUNDER
(Post 4197975)
Anytime I can get a friend to spend money, I feel great! Mike, I think you might be a perfect candidate for this. You think Dave down at the dyno would be up for playing with this setup? Maybe when we can bring yours down to the dyno, and skype Eddie in for some live tuning assistance
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I called down to daytona sensors last week. The lady that answers gave me the owners cell phone number.
I called to ask about the MAP sensor and its application in regards to a NA application. He told me that there was no advantage to collecting manifold pressure data in a NA application. I was wondering if I could use the data to program in more timing under a light load/high vacuum condition. The part of the MAP sensor operation that I'm having difficulty wrapping my head around is that the Delphi map sensor is a 0-5 volt pressure transducer. Great for measuring a boosted application as in turbo or SC applications. I would think you would need a sensor with a negative/atmospheric/positive range to measure vacuum and boost. That said, I'm not sure what the range is for the Delphi map sensor. I did read that the Delphi sensor sees manifold vacuum and manifold positive pressure as a value above zero in the 0-5 volt signal. I need to do some more research to determine if there is any advantage to collecting MAP in my application. It may be that the map data could be used in addition with the rpm at a given time to plot the 3d timing table. |
Looking at the Delphi PDF files, it appears that barometric pressure nets a voltage output of just under 5 volts and as vacuum is created in the manifold, the voltage output decreases proportionally.
Not quite sure how a positive manifold pressure is quantified with such a transducer. I'm sure I'm missing something pretty basic here. |
Different sensors have different calibrations, 1 bar 2 bar, etc. For a 1 bar (atmospheric ) sensor, 5 volts is 105kpa/14.7psi/0" vacuum/1 bar. Depending on how you want to read it. When your engine pulls a vacuum, it is still reading pressure, unless you boat in space, there will always be pressure in your intake, even though we call it vacuum, it's only pressure below atmospheric - 14.7psi
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Also, I agree in an NA marine app, due to the very linear load vs rpm, there would be very minimal gains to timing vs map instead of timing vs rpm. You can use the rpm as your load curve
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I know on my personal boat, and some of my boat buddies boats, which are heavy twin supercharged engine vee bottoms, the rpm/load/manifold psi, is not very linear to rpm.
For example, our lake can be as calm as can be, where a duck can leave a noticeable wake. Then there are days it can sink freighters. So, on some days, I could be out running say 65mph, drives trimmed out, tabs fully raised, light on fuel, and be say 0 inches on the gauge at 4000RPM. Then there are days when its sloppy rough, I got a full 220 gallons of fuel on board, some fat chicks, drives tucked, tabs dragging, and be at 3-4lbs of boost at 4000RPM. For me, I'd want to take advantage of the map sensor function. This whole concept was around way back in the days of vacuum advance distributors. High vacuum, lots of timing. Low vacuum, not so much timing. It actually was a good setup for its time, but most guys would get angry and plug the vacuum advance , mainly because they just didnt understand it. I remember the first time I saw a sun distributor machine, thought it was the coolest thing ever! I had aquired a mint condition one several years back. Like a dummy I sold it to a guy, I should have kept it. It would have been cool to put in my magic room someday. :D |
Originally Posted by HaxbySpeed
(Post 4272344)
Different sensors have different calibrations, 1 bar 2 bar, etc. For a 1 bar (atmospheric ) sensor, 5 volts is 105kpa/14.7psi/0" vacuum/1 bar. Depending on how you want to read it. When your engine pulls a vacuum, it is still reading pressure, unless you boat in space, there will always be pressure in your intake, even though we call it vacuum, it's only pressure below atmospheric - 14.7psi
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I agree on the boosted deal. I was responding to VC, about whether there would be worthwhile gains on his na deal to run a map based timing setup.
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Originally Posted by HaxbySpeed
(Post 4272513)
I agree on the boosted deal. I was responding to VC, about whether there would be worthwhile gains on his na deal to run a map based timing setup.
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Originally Posted by MILD THUNDER
(Post 4272166)
I was just discussing this today on the phone with another oso member who wants to try it on his big power blower motors. I have yet to purchase anything though. Its not really feeling like spring is anywhere near!
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Good to know Mark! My two options are the msd 6530 vs daytona sensors. While the msd is a bit cheaper, I am kinda leaning towards the daytona boxes. Seems like they have a few more features , and from what I hear top notch quality.
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Originally Posted by Black Baja
(Post 4198481)
I finally did get the detonation taken care of with a 20% mix of race fuel and 93 pump gas.
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Some great info here, definitely will keep tabs on this. May be a direction I go in the future as well
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So tell me if i have this correct: take either the MSD or Daytona box, you have to lock your distributor at where you want your highest advance.. Lets just say 42*, now you set your start up retard to like 15* to 500 rpm then however your going to program through the rest of your curve, bla bla bla... Now? what happens if the box takes a poo? And the box won't take timing out... you are locked at 42* and will idle fine and you go up on plane and blow your motor cause it didn't retard??? WTF??? I would really rather have a box that could add timing.. not just take away timing. So, do I have this wrong? and is there any fail safe?
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Originally Posted by Bawana
(Post 4272590)
So tell me if i have this correct: take either the MSD or Daytona box, you have to lock your distributor at where you want your highest advance.. Lets just say 42*, now you set your start up retard to like 15* to 500 rpm then however your going to program through the rest of your curve, bla bla bla... Now? what happens if the box takes a poo? And the box won't take timing out... you are locked at 42* and will idle fine and you go up on plane and blow your motor cause it didn't retard??? WTF??? I would really rather have a box that could add timing.. not just take away timing. So, do I have this wrong? and is there any fail safe?
Also, in reference to the daytona sensors..... The CD-1 comes with a new coil (worth 80 To 100 bones), a USB patch cord and all the software. It also has a +5 volt terminal for powering up external sensors (MAP sensor) |
Exactly what i was worried about Banana, that box takes a dump goodbye motor.
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Originally Posted by vintage chromoly
(Post 4272610)
You cannot "add" timing. You can't trigger the spark "x" amount of crankshaft degree before the distributor (or crank trigger) actually passes the magnet. You can only take timing out.
Also, in reference to the daytona sensors..... The CD-1 comes with a new coil (worth 80 To 100 bones), a USB patch cord and all the software. It also has a +5 volt terminal for powering up external sensors (MAP sensor) |
I'm not sure what the failsafe is on them. But in reality , a piece of dirt in a carb needle and seat can burn up a motor. A fuel pump failure can burn up a motor. Moisture in a distributor cap causing crossfiring can burn up a motor. A thousand things can fail and take out a motor.
Its like asking , what happens if my lifter wheel falls off on my roller lifters ? Ehh, I'm gonna stick with flat tappet because no roller wheel to break. These boxes do sort of the same thing an ecm does on a fuel injected car or boat. If they were to fail internally , or not do what they are supposed to you can have issues. Maybe that's a question for the guys who designed these boxes as far as what can fail in them and what are the effects of it failing. Does the daytona sensors box have options for knock sensors ? |
Originally Posted by adk61
(Post 4272657)
... Capacitive discharge with a controller uses the trigger from the distributor as a reference signal, the coil is what is discharged in order to create the spark at the plug and the controller is what dictates when the coil will do that... if I'm understanding correctly as to how the system works
The "box" is where the signal is processed and any delay is introduced in a locked distributor application. I think you have it right in your mind. |
Originally Posted by vintage chromoly
(Post 4272610)
You cannot "add" timing. You can't trigger the spark "x" amount of crankshaft degree before the distributor (or crank trigger) actually passes the magnet. You can only take timing out.
Also, in reference to the daytona sensors..... The CD-1 comes with a new coil (worth 80 To 100 bones), a USB patch cord and all the software. It also has a +5 volt terminal for powering up external sensors (MAP sensor) |
Originally Posted by vintage chromoly
(Post 4272663)
The "trigger" is usually inside the distributor but sometimes a crank trigger is used. When the magnet passes the pickup a signal is sent to the ignition to discharge the coil and send that charge to whatever spark plug the distributor dictates.
The "box" is where the signal is processed and any delay is introduced in a locked distributor application. I think you have it right in your mind. |
I don't believe there is a dedicated input for a knock senator.
There are three I/O's on the box and two are dedicated to data logging. The third is programmable. You could use it to switch a nitrous system or to collect MAP. Give them a shout. The guy was gracious in answering all my rookie questions. |
Ok I got a stupid question, I have preloaded maps in my Marine Crane boxes...
These are Mercury timing tables , no good? http://33outlaw.zenfolio.com/img/s9/...86820522-3.jpg http://33outlaw.zenfolio.com/img/s5/...02661519-3.jpg http://33outlaw.zenfolio.com/img/s12...93666793-4.jpg |
I think the problem you'll find with those maps is no timing at idle doesn't work well with your high falootin cams, big blowers, and 1050 carbs.
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Originally Posted by ICDEDPPL
(Post 4272689)
Ok I got a stupid question, I have preloaded maps in my Marine Crane boxes...
These are Mercury timing tables , no good? http://33outlaw.zenfolio.com/img/s9/...86820522-3.jpg http://33outlaw.zenfolio.com/img/s5/...02661519-3.jpg http://33outlaw.zenfolio.com/img/s12...93666793-4.jpg It's not that the merc timing table is "bad". It's that the Daytona table (or any real time data referencing table) is constantly manipulating the timing based on rpm and MAP if you program it to do so. |
Originally Posted by MILD THUNDER
(Post 4272692)
I think the problem you'll find with those maps is no timing at idle doesn't work well with your high falootin cams, big blowers, and 1050 carbs.
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I installed MSD programbles last year for 540 carb n/a engines. Engines had trouble at idle and with big props lugged when put into gear. I now have max timing @ 36 degrees, engine idle at 24 degrees, then drop back to 12 degrees for fast idle 1,200 - 1,800 rpm (in case I have to come home on one engine for prolonged periods of time) from 1,800 to 3,000 rpm straight line to 36 degrees. The difference in idle is worth the money, engines run smooth and barely lug when put in gear. I also purchased (and programed) a spare MSD box for the day when one fails. I did not understand taking time out ( graph is backwards) and called MSD for tech help - they are worthless and told me to follow instructions. I though maybe the dude was having a bad day and called back a week later same response, basicly they said if I can't figure it out I should not have purchased the boxes. I'm happy with the product but would use tech service as the bench mark before deciding between Daytona or MSD.
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Wow that sucks if the MDS tech guys were that bad... I am a member of their forum/chat site they have, its very helpful and knowledgeable. I am going to be pulling the trigger on either the Daytona or the MSD 6530... In alot of the car forums, they speak highly about the 6530. I wish Joe, Dan & Mike would have already done their motors & had programming figured out so I could have just jumped on their band wagon. LOL :circle:
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Originally Posted by MILD THUNDER
(Post 4272692)
I think the problem you'll find with those maps is no timing at idle doesn't work well with your high falootin cams, big blowers, and 1050 carbs.
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Originally Posted by Young Performance
(Post 4273035)
I'm certainly no expert, so I'm not sure......but exactly how big is a falootin cam?
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Originally Posted by Young Performance
(Post 4273035)
I'm certainly no expert, so I'm not sure......but exactly how big is a falootin cam?
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Originally Posted by Young Performance
(Post 4273035)
I'm certainly no expert, so I'm not sure......but exactly how big is a falootin cam?
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I'm no expert either, but a falootin cam is usually a cam much bigger (lift/duration) than one can effectively use! Happens a hole lot these days!
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Falootin came to be by a simple mispelling of flatfootin. Must have been a european metrosexual......imho.
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A little bit....a little bit....a little bit closer.....and yall will have EFI
:D |
[QUOTE=TooLateVTEC;4273063]A little bit....a little bit....a little bit closer.....and yall will have EFI
So if we get this EFI you speak of, is there a shot/pill/serum that can cure us. can a doctor treat this ailment? (Just Kidding I couldn't resist) we can now return to your regularly scheduled programing! |
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