touring 70 monte, convert to FI

[deadeyedck]

I have gotten some great help here before so I thought i would ask here about the fuel injection.

A little overwhelmed with the right choice for the injection system. not sure which intake injector size or ecm to run.

I want to make sure I have the right air volume, enough fuel with good reliability.

I need it to be very reliable as a top priority.

This car is a daily driver touring car 1970 monte. I worked with mark at sc&c and did the whole suspension front and rear. The car handles great now would be very smooth if not for the 20 inch rims.

engine and exhaust just got done

Did the 3 inch oval from ram air restoration into the long spintechs and 3 inch over the axle. kinda loud but sounds great.

engine 1969 427 bored .60 with nitride sleeves

heads rectangular port

11:1 compression

forged and balanced internals



comp cams 290 degree hydraulic tappet

I'm not really a fan of the carburetor style intake as far as the look but maybe its the best choice i'm not sure.

I would like to be able to control everything to take full advantage of EFI i.e. timing by using a dual sync distributor. Just tune it once and have some versatility if i decide to add some air to it later on.

thx

[Six_Shooter]

I would suggest looking at the Delco ECMs that come in the '80s to mid '90s GMs.

They are very reliable, have limp home mode (if the proper MEMCAL is selected as a close match), on board diagnositics, will control fuel and spark, come in a variety of flavours, TBI, MPFI, N/A, forced induction, etc. They can be used with a dizzy or with DIS as well.

Check out http://www.eagle-mark.com/Forums/ for information along with wiring diagrams, and many other files for a variety of applications.

I use Delco ECMs in my conversions, easy to tune, inexpensive, and just plain work.

I have a Delco ECM running the Nissan engine in my 1973 Datsun 240Z.

[MonzaRacer]

I would use Megasquirt 3, add in cam sensor, crank wheel and use 8 LSx coil near plugs, sequential fuel injection, full timing control, and it can be integrated into trans control, GPIO board all CAN connected. and its owner serviceable. No sending things off, some basic electronic testing and a stimulator board and you can diag and fix just about anything there is wrong.
90+% of the parts are available at and good electronics warehouse like DigiKey or Mouser.
Nothing against the "GM" stuff but its slow, old tech and not near as fast or adaptable as Megasquirt.

[Six_Shooter]

Nothing against the "GM" stuff but its slow, old tech and not near as fast or adaptable as Megasquirt.

That's funny...

I keep hearing that, but is simply not true.

The only MS that even compares to a Delco ECM is the MS3, only because it's finally added VSS integration, and some other things that the Delco ECMs have used all along. The MS3 has added some other capabilities, like SFI and sequential ignition, which are not needed, in 90% of applications, and only for bragging rights in the ones that do.

I haven't had to service any of my Delco ECMs, just plug them in and run the car. In the 18 years or so that I've been playing with EFI, I have had one ECM fail on me, and that was only because it got some water in it, on a particular rainy day when there was a leak above the ECM, but any electronics would have problems with that.

I've been following the MS stuff since the late '90s when it was EFI 332, and the public releases, have always lacked stuff that I felt was important, that the Delco ECMs have always had.

There's only one company that I know that offers an almost automotive grade harness connector for the MS, the computer connector that is used is simply not designed for the automotive environment, and this has been an issue for some people.

The MS is neat as a learning tool, and yes I have considered it myself, now that the MS3 is out, but I will still use the Delco ECMs, since they are easily adaptable to just about anything, they are VERY reliable, and easily tuned.

I have/am considering the MS3 for a particular project, but I don't think the ROI would be worth it.

Getting back to the topic at hand, SFI and trans control are not needed (There are OBD1 Delco PCMs that will control 4L60E and 4L80E as well FWIW), and sounds like it would complicate matters at this point.

[MonzaRacer]

Well up until the mid 90s the GM ECU was running no faster than 8 MHZ, and as for reliability, well I just prefer to use something I can build AND fix my self. AS a tech I have replaced many GM ECUs with intermittents and odd failures, each costing me time and frustration. Nothing against them, but up until the newer units that are reflashable I wasnt impressed, AND I am the guy who advocates using them a lot.
As for missing features, it was the added features I liked about MS2extra and now MS3. Heck only down side I have on Microsquirt is it doesnt control 8 injectors/coils.
As for the connector I have guys running them for years and no issues. And on the other note I have had issues with GM computer plug in terminals and having to find/buy/crimp the factory connectors.
I wont push GM over MS2 or MS3 because I have seen performance tuning issues using GM, including slower reactions to engine changes.
I have a family, 4 cars, mom,dad, son, and daughter. They all drive Fbodies and all had stock computers, for reliability they all use same engine and trans. Cars range from dads first new car an 84 Firebird, mom has first year Iroc, some has a GTA and daughter has Firebird. All cars use different suspensions as kids drive theirs.
sons car wound up with odd idle issue that made him lose off line several times, finally found it to be crappy ecu, daughters car would start shutting down while driving to school,,,,bad connectors at ECU, moms car had myriad of wiring and connector issues and dads, well after killing 4 computer sitting in garage between racing events.
Now all had same harnesses either bought from GM, pulled from clean cars or were stock. All cars had same ECU and like I said all the same.
One season on no one making final points and we did something different. These were after I went looking for different unit to replace the GM stuff.
The kids cars now have well over 100k on MS2extra installs, same TPI/HEI units, even retained knock function and cars all got faster as we incorporated wideband O2 into them. And so far no connector issues, and only harness issue was one time on sons car his O2 wiring got melted.
Now they all have different engine/trans combos. Mom just took a business trip in hers and the car had over 3k miles and she saide it got better mileage (hers was last one to get swapped out) and she hadnt done any long drives but since the new fondling orders from up on high her company has let people drive inside US, and saved cash too.
Not sure how on that, but any way, she now has an MS3 recently installed and got it cranking some serious mileage as she monitored O2 and knock sensor and with her AFR headed 355 all coated and such she was cruising in the 16 to 1 range with no issues. and I even made them vapor recovery kits and such, which really isnt hard if you can find the pump.
But as for reliability, kids in college, drag racing and away from home with no issues, when at home and drag racing with issues.
And since everyone in the family LEARNED how to pull units, hook them up and test and to deal with issues and nearly everything is replaceable on the cheap.
This is why I do recommend Megasquirt. Heck I am working on an old Hilborn mechanical unit we are going to run on batch fire with Microsquirt and DIS. My biggest issue was time and tools involved using GM stuff.
Tuner Studio is free, updated and all you need is cheap laptop.
But to each his own, if reman GM computers and repair services hadnt gone out of site, and it got harder for me to find units to use I might have stayed with GM stuff. but $300 for newer GM stuff at the low price made MS so much better.
At least for me.
and being able to overnite parts from Digi Key was an added plus.