I love doing that in my dmax,no anti lag,,just on brakes and 10lbs of boost= gone when light turns green.

Tell justin to give you my "good" tunes no brakes needed :) just instant spool

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

Eddie, thank you VERY MUCH, for taking the time to put this information up. I remember last year, discussing this with you on the phone. Its much clearer to me, when I can go back and read it.

I noticed the Daytona Sensor box, has an option to add a Map sensor if wanted, so you can build a map based on boost/vacuum, not just RPM.? What I like about that, is that in my particular combo, the RPM/Load scenerio, isnt constant. I may be cruising on calm water, with a light load, at 4000RPM, and 100KPA. However, fuel tanks of fuel, some rougher water where I may drop the tabs, tuck the drives, and now Im making 3psi of boost. So, even though the RPM is a constant, the manifold pressure isnt always.

I did notice the Daytona Sensor box advertises a "Idle Stabilization" feature.

Even though my setup has been working good, and hasnt broke anything, I'm always willing to try something new. I really like the idea of being able to crank the engine over with say 10* of advance, and as soon as it starts the timing can be increased, to whatever I like at idle. Even though I dont have super high pitch props, or the tall gears, dropping it in gear with the 17" SSM props will sometimes want to kill the engine.

Aside from adding some complexity with the tuning (which I am sure you are more than capable of), I really don't see a down side to doing this. What are you figuring, about a grand a motor all in as far as cost is concerned? I mean hell, even if it wasn't your bag, you could make a straight 34 degree table and be back where you were.

Actually, that might even be kind of cool to just quantify the difference in manners, economy, and performance between the two. Crap, now you have me geeking out on this.

Then it sounds like a no brainer to me. Especially if it can reference a MAP sensor. That will make all the difference in the world. Using your example of cruising at 4000 rpm, you could potentially see a difference of 3-5 deg of timing. If the MAP is at 90-100 Kpa, you could possibly run in the 35* area. If the load is higher because of a heavier load (mulitple fat chics) or you are dragging tab (being a *****) and the boost comes up to 3-4 psi, you would want to drop the timing a few deg to say 31-32*, since there is no knock protection. This would help save the engine in the high load situations, but allow you to make the most of economy when cruising with it trimmed out.

Let me know if you decide to pursue it. I would be more than happy to help as much as I could or supply you with a timing vs rpm vs MAP table to get you started. Sounds like it could be a really cool project and a worthwhile upgrade.
Eddie

The Daytona Box works with the TBolt Dist's. Big plus. Some others don't.

Another big plus is that they sell a phased TBolt rotor. Back when it was a Crane Box (Crane wasn't programmable but it had a bunch of different curves you could chose just by turning a dial) , you had to mod the dist rotor yourself. This was a big turnoff to some people.

I've been close (mentally) to buying the Daytona Box even for my mild small block. Has great features.

I used to have a Crane HI-6M (made by Daytona Sensors) and that was dead realiable and a great box.

Nothing like good box ! LOL.

I think I'll definitely be calling if i buy them. I understand the features it has, and the principle behind it. However, setting up a multi dimensional timing map, I'm gonna need some help! Thanks !

I have the Crane Boxes now. They are the 6000-6440 box, without the built in ign curves. But it does have the internal rev limiter. I've been extremely happy with them, they just work. Just feature limited.

thanks mild,now you have me think about droping 1500. bucks and try this.