The MegaSquirt Project has experienced explosive growth other the years, with hundreds of new MS installations occurring every week - a phenomenal success! MegaSquirt has been successfully used in all aspects of Internal Combustion engine applications including R&D, Industry, Race, and Research. The MS project has transformed itself from a simple R&D project into a full-featured mature engine control system. To reflect this the support structure has also changed to meet the needs of MegaSquirt Users.
Moving forward, the R&D forums for MegaSquirt project are in a read-only mode - no new forum posts are accepted.
However the forums will remain available for view, they still contain a wealth of information on how MegaSquirt works, how it is installed and used. Feel free to search the forums for information, facts, and overview.While the R&D forum traffic has slowed in recent years, this is not at all a reflection of Megasquirt users, which continue to grow year after year. What has changed is that the method of MegaSquirt support today has rapidly moved to Facebook, this is where the vast majority of interaction is happening now. For those not on Facebook the msextra forums is another place for product support. Finally, for product selection assistance, all of the MegaSquirt vendors are there to help you select a system, along with all of the required pieces to make it complete.
This forum is for discussion of MicroSquirt (TM) from Bowling and Grippo. The MicroSquirt information site is at www.usEasyDocs.com
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Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
I am just getting started on tuning new huge v8 motor with essentualy a throttle body setup. Of the people that have MS2 up and running on X-Tau and Normal AE.... What sort of settings are you finding works. Are you running normal AE? Are you tapering normal AE off as RPM raises. What sort of TPS thresholds are you using? ....
Eventualy I would like to help Lance wright a "guidlines for X-Tau setup"
I recently tuned my first MS-II car(s) and I found the TPS-based enrichments to be a little more tricky.
I always disable accel enrichments and first try to slope the VE table upwards at MAP pressures just above idle, all the way to 100kpa. Try to get a good free-rev this way, then I add TPS enrichments on top of that. I noticed that reducing the lag filters (by raising the TPS and RPM lag filter numbers to around 85) seemed to help the TPS enrichments. I also have noticed, people tend to use too short of an accel time, and too much fuel. My ears tell me that accel time should be more like .3 or .4 sec at smaller pulsewidths.
Right now I have X-Tau set to .1 thruout the entire 12x12 table with default settings on all the options. I get PW1 of close to 2-4 ms at low RPM and low tps readings. AE at about 2ms off idle and 4%/sec trigger. All standard AE is off by 3000 rpm. This thing is a way over-camed 426 Hemi with 4 650 cc injectors set to 4 squirts/alternating. Idles ak like 75 KPA cruses at around 45 KPA. Idles at like 950 in gear 1400 out of gear. Right now there is no IAC. I am close to stoch thruout all steady state idle and cruse under about 65MPH
Note: The ini has been screwed with to get all this stuff optional at the same time.
I set my VE Map like Scott does, allow more fuel just above idle and drop in a bit of AE. With my manual trans car I have found that if I weight AE toward mapDOT more I get a smoother transition between gear changes etc.. TPS is very tricky to tune the 'tip-in' throttle (especially if your VE isn't 100%) where mapDOT will detect a change in load and respond accordingly.
With the X-Tau side of things on my particular setup I had to reduce the puddling factor to about 22% but leaving the Tau table alone, otherwise it would bog down then launch. After taking my brother for a 15km run last night I was impressed with how 'streetable' it is now and commented that whatever I did (X-Tau AE) has made it work as well as an OEM computer.
Sydney, Australia
Successfully MS2 v3.0 squirted 1971 Holden Monaro HQ
400 Pontiac, ported #16 heads, Tomahawk intake with custom plenum using LS1 78mm throttle body dialed in with a TechEdge 2E0 Wideband Controller.
Here are some thoughts from my testing on my car, it represents extremes of throttle sizing, displacement and mass which have made it tricky to tune.
I now have it dialed in using 2.6 x-tau only AE after alot of experimentation, here are a few things I've found:
The x-tau table shouldn't have large value changes. I settled on a range between .04-.14 and tried to have no more than .01 differences between boxes, higher value changes resulted in fluctuating pulsewidths.
I settled on a puddle factor of 34%. Going too high on that value would probably also result in excsessive pulswidth changes.
There seem to be good benefits from using x-tau with the even the lightest of values and increasing them too much can cause wildly fluctuating pulsewidths.
I see no reason for the decel value, during normal x-tau corrections, there seems to be plenty of fuel cutting going on just from the large drops in the VE table when the throttle is lifted.
With x-tau there is no reason to use other AE. Yes, my msq has some TPS activated AE but that's just because of my worst case motor that's hard to rev from a no-load idle condition, that AE is just a bandaid.
Here's my .msq: The motor is a 7 liter v8 with 56 mm ITBs and injectors pointing at the intake valve. The motor has a small, light clutch, hence the AE bandaid.
