MegaSquirt newbie (again) looking for Bay t4 install info

[type11969]

Greetings. I have a 1976 Westy with a camper special engine in it. It is currently running stock FI, and it is pretty finicky, both due to the worn out stock FI components and the redesigned engine. Its time to go digital . . . if I had only devoted all of the time I've spent over the last few months trying to get my current setup dialed in just right, I would have a working MS system. So, a few questions.

1) I've just started to dig, but if anyone can quickly point me in the direction of some good t4 bus megasquirt builds/installs, I'd love to see what people have already done.

2) I have a MS1 sitting around from one of the group buys back in 2003 - a leftover from grandiose plans to fuel inject the t4 in my beetle. Am I wasting my time by using this as the ECU? Should I buy a more up to date kit, or is the MS1 still relevant? I'm mostly interested in fuel control, but it would be great to have the option to do spark as well. I'm not afraid of soldering nor of a system that is somewhat cobbled together (as long as it is reliable).

Any help would be greatly appreciated!

Thanks,

Chris

[Clonebug]

Nothing wrong with MS-1.

What version board do you have??? That would probably make a difference.

Mario Sells a nice trigger wheel for crank fired ignition on a T-4.

http://www.thedubshop.net/shopping.html is where you can find his products.

There are so many options out there you need to do a little research on how far you want to go.

[Piledriver]

I have run MS3+MS3X on a v1.01 mainboard from the first MS group buy...

The V3x mainboards are much better made/heavier traces and better design, but the early boards are 100% electrically compatible.
(the primary difference being the v3 added 2 channels of VR circuits, but those are optional and not needed in some setups)

It's actually ~the best thing to happen to a v1.01 or v2,2 mainboard as pretty much all the "mods" you would have to do to it are dealt with via the MS3/MS3X, so zero mods //hacking required on the mainboard other than routing some IO out on the spare pins on the V2.2, and even that is optional.

This is of course not a supported configuration, (It Is Not Something We Talk About) and depending on what setups you try you may or may not cuss your lack of VR amps on the mainboard, but otherwise electrically it works just fine.
To bolt the MS3 down you have to drill 2 holes and reroute a couple traces, I did one corner (no trace reroute needed) and ran a 1/4-20 nylon bolt through the MS case to clamp down the MS3 daughtercard--- much more secure than the std design.

You MUST be your own tech support to run this sort of config as the devs will not want to hear about it, the MS3 docs are strictly written for v3x mainboards. YOU must be able to translate/work around any differences.

I'm currently running on a v2,2 mainboard as it had the spr1-4 pins routed out w/o hacking.
(you can do it on a v1.01)

There are also trigger wheel options other than crank based that are available and about to be available at a reasonable price.

...On an ACVW you do not get huge amounts of timing jitter at the distributor unless the distributor and.or drive gear are trashed.
... One missing tooth wheel at the distributor and you can run sequential with one sensor.
Redline Weber sells a modded 009 with a 24-1 wheel and VR for this purpose
Mario is likely to have something electrically similar but much better looking (and running on ball bearings) RSN.

This is a bolt-in and twist to set your timing setup, very intuitive setup if you are old skool.

[luftvagon]

I strongly urge you to go with ignition and fuel... Makes things much easier in the long run. I started with FUEL ONLY with my setup, and quickly hated all the quirks that come with it. I am so glad I did the ignition too... for not much more, dollar and time wise.

[Max Welton]

Actually, I can see going either fuel-only (which I did), ignition only or even just using Megasquirt only for its considerable logging capabilities to begin with.

Any of these approaches allows one to learn the entire system incrementally. I found this to be a very practical approach.

Max

[luftvagon]

I respectfully disagree.. Because you can just "copy" over distributor ignition curve into the ignition table, and leave it as is if you don't want to mess with it.
Having to mess with unreliable tach signal from negative side of coil is a disaster, even if it is opto-isolated.

[Max Welton]

I respect your viewpoint. You may have had a different experience getting a solid tach signal from the negative side of the coil. Mine just worked.

I will say that when I did switch to a 36-1 trigger wheel and VR sensor, it took some fiddling to resolve some self-inflicted issues. I had the VR wired backwards and the sensor-to-wheel distance was inconsistent. When I did have to work that all out, the fuel side was already working well.

Everybody works differently.

Max

[luftvagon]

I respect your viewpoint. You may have had a different experience getting a solid tach signal from the negative side of the coil. Mine just worked.

I will say that when I did switch to a 36-1 trigger wheel and VR sensor, it took some fiddling to resolve some self-inflicted issues. I had the VR wired backwards and the sensor-to-wheel distance was inconsistent. When I did have to work that all out, the fuel side was already working well.

Everybody works differently.

Max

We agree to agree!

[Max Welton]

Absolutely. I did do them both, just not at the same time.

Max

[type11969]

Awesome, thanks guys. Looks like I have a v2.2 board, sounds like it is a reasonable starting point. Time to do some research - any noteworthy Bay t4 build threads?

Chris

[luftvagon]

I have microsquirt running in my Vanagon. Not sure what firmware you will or can load on that board.. but if you have any questions regarding msextra and stock FI hardware, let me know.

[type11969]

Cool, I'd be interested to know what stock hardware you did end up using. I was planning on using the stock plumbing, TB (I have a throttle position pot), injectors (recently had them rebuilt), resistor pack (new, needed for the stock injectors, right), CSII as the coolant temp sensor, AAR for cold idle air bypass (for now at least), hmm what else. I was thinking about using a gutted stock ECU housing to mount everything and use the stock harness as much as possible for wiring (just rebuilt it, all new). What did you do for an air filter? Connection for PCV?

If you have a build thread, please point me towards it.

Thanks,

Chris

[luftvagon]

well, i say i used everything.. but in reality, i'm using stock intake runners, plenum, throttle body (didnt need tps), stock fuel pressure regulator, $30 vanagon fuel pump alternative, stock fuel lines (updated to SAE 30R9)....

[] HighZ Injectors - Newer Vanagon Injectors (direct replacement and lets you eliminate old aging resistor bank). They are $25/pop with AutoZone/Advance/Oreilly discounts.
[] Ford Taurus cold air intake with ford intake air temperature sensor
[] GM CTS threaded via adapter into TSII spot.
[] GM 1-Bar MAP Sensor from NAPA with life time warranty
[] Mario's T4 crank trigger (did not require removal of the fan housing, but requires long socket extensions..) + Mario's Distributor Hole Plug
[] IGN4 Coil + DIYAUTOTUNE QuadSpark (only two drivers used, and two drivers are backup)
[] New Coil Wires
[] Corvette canister purge solenoid for FAST IDLE (http://www.shoptalkforums.com/viewtopic ... 6&t=142410)
[] LC-1 WideBand o2 Sensor
[] $30 Fuel Pump (http://www.itinerant-air-cooled.com/vie ... 50&t=11381)
[] 2 x Bosch Relays
[] Various pig tails for all sensors
[] Wiring, and cable management tubes
[] non-insulated butt splices
[] shrink tubing
[] various electrical connectors.
[] 12 gauge, 14 gauge, 16 gauge, 18 gauge, and 22 gauge wiring...

If you want a better TB and TPS, you can adapt older Hyundai Elantra's (http://www.thesamba.com/vw/forum/viewtopic.php?t=574508).
That will be my next upgrade, and fixing tidying up my wiring... I ended up "Y" merging my grounds all over the place -- while very fast and effective... looks like total poop.. Instead.. I am going to run common ground bus, using fancy 12v distribution blocks.....

[type11969]

Whoa, awesome, thanks. I thought the tps was needed in conjunction with a MAP - is it just redundant? I do like the idea of highZ injectors - mostly to tidy up wiring, but since my injectors were recently rebuilt and my resistor block is brand new . . . hmm. I seem to recall using ford mustang injectors the last time around - think they dropped right in to the stock runner ports.

Thanks again,

Chris

[Max Welton]

TPS is not vital. But it can be useful.

The main function that is only available from TPS is something called "flood clear". Flood clear, as the name suggests, is used to clear a flooded condition. Basically you define TPS value above which the injectors are turned off (if cranking and not running, something else you get to define).

TPS can also be used to trigger the accelerator enrichment, kind of like the accelerator pumpon a carb. OK, actually that is TPS dot (the rate of TPS change). But some folks use MAP dot (rate of MAP change) to do the same thing. TPS dot and MAP dot can also be used proportionally.

Of course it's also nice just to see the throttle position in the logs next to all the other parameters.

Max