| Author | Message | ||
     M1combat |
I just read through most of the mega squirt website and have come to the conclusion that the device will NOT work on a sequentially injected system w/o MAJOR modification. Can anyone confirm that the XB's are indeed sequentially injected? | ||
| Wyckedflesh |
What your not realizing Don is the megasquirt is a stand alone FI and not an add on. It doesn't matter if the XB is sequential when you use a MegaSquirt system as the DDFI disappears from the picture. | ||
| M1combat |
It does matter... sequential FI is triggered by a CPS. There would need to be some massive re-working of the MS code for it to be able to figure out the pulse timing based off of the CPS (unless the CPS triggers once per crank rotation, but I doubt it...). If you have the cam position sensor triggering the injector pulse now, and you have an FI system (the MS) that can not decode a signal moving at any other speed than the crank, what would you do? You would have to fabricate your own crank trigger... Probably worth it if you were already punching out the engine, but not if you were just going to set this system up now in anticipation of the big bore goodness about to happen  . I realized this while reading through the megasquirt manual (which is quite extensive mind you). Sooo, can anyone confirm that the injectors are triggered by the CPS? If so... is anything else (I suspect spark timing would be as well)? If not, does the cam/shaft where the trigger is located operate at 2X or 1/2X the RPM? If it's 1/2, maybe one could fabricate a second trigger on the cam for the CPS to fool the MS into thinking it has only one crank trigger that is operating at the same RPM as the crank? Of course, it would have to be VERY precisely positioned. Maybe you could tell the MS that it's installed on a VERY low RPM 2-stroke? There is at least one person who has made an MS work on a harley but it was a 94 FX as I recall. I don't think he has anywhere near the same system we do. I think the only solution is a crank trigger. I do have a post on the MS forum that seems to be getting at least a little bit of attention so we'll see. Most of the people over there are wondering why I don't use the Screamin' Eagle system though, so who knows what will come of it. I've already explained that it's not a Harley and the EFI systems are not the same. | ||
| Opto |
Don there is mention in the beginning of the manual re batch vs sequential injection, and there is heaps of info there about triggering. It can be triggered from the ignition coils or hopefully even better the tacho out pulse. The FM states the XB's use sequential port injection. The cam runs at half engine speed, the CPS lets the ecm know at what position the crank is at so the ecm can control spark and FI. To run the MS on an XB would require either getting another ignition system and tossing the ecm, or keeping the ecm for all functions except for triggering the injectors. Tossing the ecm could open Pandora's box, keeping it would require making dummy loads for the injector outputs to keep the check engine light off, and there could be some major issues like drifting AFV which could affect the spark map if you take the FM DDFI "general" description on page 4-3 2004 Lightning models literally. I really hope this isn't the case. The advantages could be smoother running and no more "playing up" when the weather changes and waiting for the ecm to re-learn. The fuel delivery should be pretty spot on all the time since the MS also uses a built-in MAP sensor. You can also choose when it will run closed loop, if at all. | ||
| Fullpower |
i think a stand alone ignition such as an HI4 or dyna 2Ki will fit right into to the cam cover. i dont think the the piston tops are real picky as to who gets the first shot of fuel, just so long as their portions are roughly equal they will get along fine. | ||
| Rr_eater |
My brothers VW is running on megasquirt, and its only timing reference is the tach signal from the dash! It's a 1.8ltr 4cyl, fires in batches of 2, running a contant datalog through his laptop (could be tough on a bike) is FULLY programable, and the box would indeed fit inside a gutted airbox (tried last weekend, no problem fit)!! THE catch is, tuning. But baseline maps are out there on MSEFI.com and yahoo groups, and baselines run REAL fat, so you are always tuning down the fuel, not up. when the factory warranty is up, I will most likely go this way, as by then he and i will have at least 2 cars running full time on it. Sensors are the tough part, if you want to call it that, and it is not a plug and play system by any means. Yes, check engine lights could be an issue, unless you leave the ecm in and dummy load it, but there ways around everything, if you are willing to work at it. It can control cold idle solenoids, fuel pump relays, has hard and soft cutoffs fully adjustable, the list goes on and on....... Do some reading on msefi.com, poke around in the motorcycle stuff, see all the guys who do make it work (not seen any XB buells yet, but there are tubers running it in there). The only thing I have not looked into, is most of the documentation talks about 4,6,8 cyl's, but the sampling rate on the tach input can be changed as well, so i dont really see a problem there either, just have not researched it yet is all. Dont throw it out the door just yet, do some reading there, then decide if it is too hard (NO WAY, its really way simple) Bruce | ||
| M1combat |
It seems pretty simple... There's certainly a little math involved, but it's simple math. Also, there are additions to the MS that will control spark. Maybe I read that when I was reading through the MS1 manual... I read a good deal of that before I even figured out that there was an MS-II... Go figure . It seems like it should work running off the tach or coil... I don't have the hardware but has anyone checked the accuracy of the tach from 900 RPM's and up? If I go this route I'll most likely end up running the MS spark timing module as well. Can any of you think of a reason why a person couldn't use both injectors for both cylinders? | ||
| Opto |
You'd have to use both injectors and they'd fire together. As Bruce said it's not that difficult but it does require effort. Don there is an Ultra MS coming out soon that will do the ignition map as well, but as Fullpower said there's proly no reason you couldn't run a HI4 or Dyna. | ||
| M1combat |
Soooo, It looks as if the Buell uses a Hall effect sensor (as most late model harleys do?). This sensor seems to have a few (five) triggers. Does anyone know exactly what events those triggers are aligned with? I assume TDC for one of the cyl's and open/close of the intake valves. Would a new trigger need to be machined? Understood about the Ultra Squirt... I think you can get all of the functionality of that box by adding the current boxes together? I'll have to do some looking around and see if one of the MS type DIY boxes will do single fire... (Message edited by m1combat on September 10, 2004) |
