View Full Version : mega talk


parish8
01-16-2005, 11:57 AM
lets talk in here rather than get any farther off topic on vho's thread http://www.ls1tech.com/forums/showthread.php?p=2320386#post2320386

parish8
01-16-2005, 12:01 PM
"Hey Parish,

Are you supplying fuel in a linear curve? and what are your variables? I think the mega squirt would be a cool retrofit on an older engine.

As far as fooling the injectors by installing a resistor: I think it would work easily unless the PCM measures a set voltage drop rather than just any voltage drop. I imagine a 1k resistor would do it, but I wouldn't know."

the mega is great on older motors and there are ways to tie it into distributors to control timing. there is a VE map that you adjust for your fueling. it is based on rpm and manifold presure. the mega makes adjustsments based on iat's and coolant temps and figures pulsewidth to send to the injectors.

parish8
01-16-2005, 12:04 PM
the best features are the tuning is on the fly, you click and the fueling changes are made, just that fast. here is a write up >> http://www.ls1tech.com/forums/showthread.php?t=245059

check that out and let me know what other questions you have.

NovaTime
01-16-2005, 12:05 PM
I am looking on the website. Well I do have an electrical engineering degree and I'm pretty good at assembly language coding. I think I will have to get one of these kits and mess around with it on my classic car.

NovaTime
01-16-2005, 12:13 PM
I think expanding the VE table would be a good idea....This is killer, I'll have to dig up an MPFI system to try this on.

parish8
01-16-2005, 12:17 PM
expanding? why. it goes from 0-250kpa(vacume to 21psi boost) and any rpm range you would want.

NovaTime
01-16-2005, 06:52 PM
I read somewhere that you were able to have 8 adjustable points. I haven't re-read closely yet, but I meant expanding the number of points you were allowed to have.

parish8
01-16-2005, 07:27 PM
the original mega had a 8x8 table, newer versions have a 12x12. the thing to remember is any data point between 2 points is extrapolated makeing the table prety much an infiniate number of data points. you basicaly set up a curve with 12 points on it. it is prety acurate. then combine that with the ability to use wideband targeting to actualy make real time adjustments to the a/f ratio. i think any more points will just make tuning take more time and not be any more acurate.

NovaTime
01-16-2005, 08:58 PM
I didn't realize the newer versions had 12 points. 12 seems like it would be just right for idle-6500.

Start2Fabrication
01-16-2005, 10:13 PM
parish, forgive me if you've said this before, but why did you go to megasquirt? i know it's a great retrofit for EFI conversions, but i would have thought HPtuner or ls1edit would have been a better solution for you.

parish8
01-16-2005, 11:23 PM
it has to do with flowing too much air for the maf sensor to read. once you max out the maf it gets hard to tune, basicaly tuning blind.

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