Megasquirt project recommendations

[efi-diy]

Re: Megasquirt project recommendations


I think the adapter board doesn't really give you all that much. It takes maybe an hour or two to just take a factory harness, snip off the old connector, and connect the leads to your MS harness. I'd recommend wiring it yourself first, then if you find yourself mass producing them, go with the adapter boards later perhaps?
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Close - the Megasquirt DB37 connector is a pain to wire up - most of the automotive wire insulation diameter is larger than what used in the telecomm applications so its harder to get the wire on the contacts if using a solder cup style connector or to get the contact into the housing if using crimp on contacts- you can do it but its a pain. Depends what you start with for a harness.

If your starting with a GM TBI harness it'll save you a bunch of time as the adapter has the required relays to allow the engine to start on base timing like GM intended if using the 7 pin HEI module, and it inverts the fuel pump signal so you don't have to rewire with the GM fuel pump relay. MS switches the fuel pump relay to gnd. and the GM one need +12 to turn on. Also has output to control the lockup converter for automatics and the needed parts to hook up the TBI style knock sensor. Although the stock TBI harness doesn't support an electric cooling fan - the adapter board brings the control signal out on pin A2 of the TBI connector. So with a little bit of wiring by using the EGR wire - just moved it in the TBI connector to pin A2 and hooked it up to a OEM type fan relay andf now have fan control.

[shaun callaway]

Re: Megasquirt project recommendations

diy has the 4bar map daddy that goes right on the board and has a baro sensor next to it.

http://www.diyautotune.com/catalog/mapdaddy-sensor-with-barometric-correction-p-117.html

[shaun callaway]

Re: Megasquirt project recommendations

dont neep a big mass air flow sensor if you put the map sensor on the board or the one that bolts on to the firewall then all you need to do is run a vaccum line for it and the wires of course. (speed density)

IAT (gm style/ac delco)
CLT (gm style/ac delco)
Widebands from Innovate (DIY AUTO TUNE)

should be good to go with these basic sensors

[JoeyG]

Re: Megasquirt project recommendations

Just downloaded and browsed the C source code. Been awhile since I did any real C development. Used to write a lot of serial datacomm stuff, way back when, serial packet protocol design, process control and the like. It'd be very interesting to see a high level flow and logic design on this stuff. I understand that besides mass air flow, oxygen sensors in the exhaust help keep air/fuel mix in range. Outside of tach input, what other sensor input does the unit monitor or rely on ?

And, how sophisticated is MS, in regards to tweaking power / torque curves at different RPM bands, etc. ? Not that I know a lot about it, but it'd be interesting to have that degree of control over performance.

Also typically looks for MAP (Manifold pressure) probably a knock sensor of some sort, inlet air temp,ad engine coolant temp. ;)

Re: Megasquirt project recommendations

Just downloaded and browsed the C source code. Been awhile since I did any real C development. Used to write a lot of serial datacomm stuff, way back when, serial packet protocol design, process control and the like. It'd be very interesting to see a high level flow and logic design on this stuff. I understand that besides mass air flow, oxygen sensors in the exhaust help keep air/fuel mix in range. Outside of tach input, what other sensor input does the unit monitor or rely on ?

And, how sophisticated is MS, in regards to tweaking power / torque curves at different RPM bands, etc. ? Not that I know a lot about it, but it'd be interesting to have that degree of control over performance.

[dieselgeek]

Re: Megasquirt project recommendations

Thanks for the info You do cool stuff.

Is there a website (hopefully with photos) that documents the build on The Exterminator ? I found Barrys Speed Shop online, and a few references to The Exterminator, but no real meat on the build.

The Exterminator is nothing!! At Spectre, our CFO had a clean 1950 Dodge B2B pickup truck, with a flathead six. The motor was in *perfect* condition. We hit the junkyard, found a TBI off another Dodge Aries car, got an adapter plate made, and put a return fuel system in the truck. You have NEVER heard a flathead run so damned smooth, it would happily idle at 400rpm... perfect cold starts, practically doubled the fuel economy, and the guy uses it every weekend for trips to Home Depot, etc.


Build details on the Exterminator, this is all I know: we got a call because the car had completed it's "tv show" but ran really rough. It had a "Carabine" EFI system on it. We were asked to make it drivable for the new owner. In Carabine's defense, there was a wiring mistake on the original install, but was Alpha-N only, so we replaced it with a speed-density eMS-pro. It had 2 160-lb injectors, and 2 60-lb injectors in the "Hat" (or whatever you blower guys call it) with the BDS injectors, hoses, and dist. block. Looked exactly like a mechanical setup! Anyways, we got it running really good. When we'd run it on the dyno however, it kept having valvetrain problems. carjunkiechad to the rescue it was fixed and sent out the door. Never heard anything good or bad about it since, and that was 6 months ago. All I have from the install are some pics my girlfriend took.

-scott

[dieselgeek]

Re: Megasquirt project recommendations

Dieselgeek would mind divulging in a little more detail why your recommending MSnS Extra.

In respect to using this as a learning experience how would you approach it?

TBI truck with MS 2 and adapter boards, MS-1 doing the wiring myself, MS-1 extra?

I like MS1-Extra because it's no harder to learn than the other versions, but it's got by far the most features. To me, it's really the only Megasquirt version that's truly comparable to other commercial standalone EMS's.

That being said, MS2 Extra is *so* close to being my new "default recommendation" - they have almost everything working in there, that the old MS1-Extra had.

I think the adapter board doesn't really give you all that much. It takes maybe an hour or two to just take a factory harness, snip off the old connector, and connect the leads to your MS harness. I'd recommend wiring it yourself first, then if you find yourself mass producing them, go with the adapter boards later perhaps?

Re: Megasquirt project recommendations

Ok, so tell me if this stuff has possibilities for me.

I'm currently running a BBC with 2 x 750 cfm 4150 HP carbs on top of a 671 blower. I have an MSD Digital-6 Plus box, Blaster-2 coil, Mallory Unilite distributor and a pretty raspy roller cam. I'm also using a TH400 with a transbrake wired into my MSD two-step rev limiter.

Can I adopt/adapt Megasquirt to work something like an old style Enderle injector hat on top of this blower ? That would be a pretty cool thing, using old school injection hardware with new injection management technology. This is the sort of project that could be a ton of fun to dive into but I don't want to introduce something that will hurt me on the street or on the track.

Any feedback would be helpful.

Thanks

Answer = YES.

BDS makes some cool accessories for running old school injector setups, with newer style electronic injectors. They have distribution blocks, braided line, and threaded injector bodies so you don't have to run a new style fuel rail. And the stuff is surprisingly cost effective too.

We did that car "The Exterminator" for barry's Speed Shop, hid all the electronics but ran the BDS stuff on top of a 8-71 blown 454 with a lot of success. Just make sure you size your injectors (quantity also) properly to the application.

-scott

Thanks for the info You do cool stuff.

Is there a website (hopefully with photos) that documents the build on The Exterminator ? I found Barrys Speed Shop online, and a few references to The Exterminator, but no real meat on the build.

[dpaqu]

Re: Megasquirt project recommendations

Dieselgeek would mind divulging in a little more detail why your recommending MSnS Extra.

In respect to using this as a learning experience how would you approach it?

TBI truck with MS 2 and adapter boards, MS-1 doing the wiring myself, MS-1 extra?

[JeffMcKC]

Re: Megasquirt project recommendations

Yes, that intake would be close to the second harmonic, and make lots of TQ.

[dieselgeek]

Re: Megasquirt project recommendations

I have been fiddling with the idea to take an old Crossfire setup, mill off all the extranious crap and megasquirt it with a decent fuel pump and identical throttle bodies. Be kind of cool looking - a crossram with throttle bodies. For torque it should work well with those long runners.

Do it!! it's not like you wouldn't have help here. Quote a few MS-literate people on this board.


Goat Racer
CDMBill
carjunkiechad
shaun callaway
efi-diy
me
The Silver Buick
revolutionary


there are more I am sure.

-scott

[RacerRick]

Re: Megasquirt project recommendations

I have been fiddling with the idea to take an old Crossfire setup, mill off all the extranious crap and megasquirt it with a decent fuel pump and identical throttle bodies. Be kind of cool looking - a crossram with throttle bodies. For torque it should work well with those long runners.

Re: Megasquirt project recommendations

A little off-topic, but...

At one time I was a diesel mechanic (among other things) many many moons ago. I looked at the possibility of using a Roosamaster injection pump on a toughened-up small block chebbie to produce an injected smallblock engine (either gas or diesel). Idea was to replace the distributor with the Roosamaster and pretty much adapt the SBC to handle injection. I still think it'd be a pretty cool project but prolly not too cost effective, given todays electronic management packages.

well, you'd have to put a throttle on it for gasoline. Also, would the gas engine be "direct injected" since the injectors on the Gm diesel are run into the precombustion chambers? I know for sure the roosamaster would need to be doubled in size just to make stock gasoline HP since the gasoline BTU content is a lot less than diesel. Then there's the timing thing, you would have to modify the roosamaster to have a variable timing (not just "cold or warm" like the originals... it would need to inject before the spark event. Sounds like a lot of work to me!

Hey, I never said the idea was based on common sense <laffin>. Over the years I've had a gazillion ideas about building one-off stuff like this. There was the sliding block / variable venturi carb I designed but never got around to building, and the crank-trigger-magneto direct ignition system (way before crank triggers came into vogue) and a couple dozen other hair-brain concepts. In another life I prolly would have been a mad scientist.

[dieselgeek]

Re: Megasquirt project recommendations

A little off-topic, but...

At one time I was a diesel mechanic (among other things) many many moons ago. I looked at the possibility of using a Roosamaster injection pump on a toughened-up small block chebbie to produce an injected smallblock engine (either gas or diesel). Idea was to replace the distributor with the Roosamaster and pretty much adapt the SBC to handle injection. I still think it'd be a pretty cool project but prolly not too cost effective, given todays electronic management packages.

well, you'd have to put a throttle on it for gasoline. Also, would the gas engine be "direct injected" since the injectors on the Gm diesel are run into the precombustion chambers? I know for sure the roosamaster would need to be doubled in size just to make stock gasoline HP since the gasoline BTU content is a lot less than diesel. Then there's the timing thing, you would have to modify the roosamaster to have a variable timing (not just "cold or warm" like the originals... it would need to inject before the spark event. Sounds like a lot of work to me!

[dieselgeek]

Re: Megasquirt project recommendations

Hey Scott, I have a driveshaft rpm set up for my tach I have never hooked up can I set that up like a speedo and log drive shaft rpm instead ? It reads two magnets on the u joint

yes, it requires a little "customization" on your emspro, I'm doing one for parish, GoatRacer, and on a bench here at home. I'll have it ready when you're ready for an install. Your EMS's should be in my mail box any day!!

also testing out a new plug & play harness for LS1 engines. MS has a lot of new stuff coming soon,

-scott