efi Megasquirt or not to Megasquirt?

[ShakeyC]

I worked with mega squirt on number of different applications and suggest the following to anyone venturing towards it

1. buy only from authorised source is only way to be confident its properly assembled and reliable

2. an authorised mega squirt will have proper info, diagrams and such to help you as there are mind blowing number of variables one tiny setting could give you months of headaches, most reputable suppliers will configure the unit for you.

3. power torque and efficiency is all down to the mapping and setup NOT the hardware or software, if your punch in stock dizzy timings 12, 25-30 BTDC you gain nothing over a carb! Find a tuner who can fine tune the map for you if you want absolute best figures.

4. cold start is major problem people have with mega squirt you need good cranking RPM and battery to start off with

5. please use new wiring not old corroded signal distorting wires, use the generic flying loom as much as possible with new power and grounds properly terminated to make your life easier throughout. Hence using 318i L-Jetronic is bad idea but easy stepping stone for most to add mega squirt afterwards BUT I still suggest using a new loom.

6. no fuel used on over-run is biggest single gain you can expect in terms of better mpg

7. if your tuning your engine your not restricted by fuel setups from carbs or mechanical injections you can map around problems i.e. turbos to make it drive better

8. The next best thing is ability to use a coil pack instead of dizzy for ignition timing even if you keep carbs for fuelling is next best thing for fine tuning and reliability.

9. read the relevant info several times before even touching any hardware, nobody will give you XYZ figures because every engine is different even with exact same specs, understanding what going on will save you money and you can improve things you feel need improving not someone mindless telling you to do this and that.

10. I say there is cheaper better standalone ecu on market these days, megasquirt is no longer the cheap hobbyists choice. In fact hardly open-source at all without commercial backup, after sales or support hence buying from authorised dealer gives you best quality of info available, whereas another manufactures will be able to give you a definitive answer to specific problems because the hardware is properly standardised.

11. its fun even if it runs like bag of nails you learn something new

[TKMad]

10. I say there is cheaper better standalone ecu on market these days, megasquirt is no longer the cheap hobbyists choice.

I would love to hear about better cheaper ECUs than Megasquirt. Always looking for alternatives.

[austinmf]

Great info!! I have moved from mega jolt to mega squirt. My only thoughts for change are itb 45 from racetep once they build my engine. In a way it seems straight forward.... . Monitoring this thread closely.

[ShakeyC]

For comparison sake here in UK a 4 cylinder megasquirt ecu and loom with base map from a proper supplier for MS3 (comparable spec to other systems) is £570 (ignoring ebay type fodder)

Having worked with all brands they all have thier individual qwerks

Emerald os £595 inc full mapping on dyno

Omex 600 £545

DTA S40 £495

MBE £500

Pectel T2 £500

KMS Mp25 £650

Adaptronic 420d £600

[eugene_'02]

Yes, there is maximum for certain throttle plate diameter - no I can't tell what it is. Does anybody have a formula?

I don't have a formula, but I remember recently hearing the 318i tb is around 150hp, 180 for the eta tb, and 220 or 230 for the I tb.

Another thing to consider with these, more something I noticed on the M20, is the length of the intake runners. M20 intake runners were somewhere between 20 and 24" long...that's fine for low end torque but could explain why it's hard to make hp.

[austinmf]

What spec engine? I would be happy with 150hp. No need to get a 325 tb..

[AustrianVespaGuy]

If you like to tinker and/or want an extremely reliable daily-driver 2002, than there's nothing better than Megasquirt. I would say it actually requires more electrical than mechanical knowledge though. Email me and I'd be happy to answer any questions and give you details about my experience if you'd like.

-Carl

ceichel zero two at gmail

[slash02]

There have already been some good responses which I largely agree with. Planning with MS I found was a key to a nice clean install, in addition to not getting overwhelmed during the process.

My guess, for a fairly basic setup with the 318 intake, would be about $1000. I agree that you sacrifice the cool look and sound of carbs, especially side drafts, this was partially the reason I've recently moved to ITBs. Still a lot of tuning to do, but they're fun indeed.

Could you email me? slash @ alberta02.com i'd like more pics of your setup!

[jmp88]

I started a megasquirt conversion in January of last year and made the mistake of tearing everything down and replacing everything at once. 15 months, ~$7,000, three different ignition systems, and many headaches later I finally got it to start again. There is no excusable reason that this project should have gone like that. It was more or less the perfect storm of lack of preparation. That said, I think I would still recommend it. Proper planning should take care of all of those problems.

First of all, it shouldn't take so long to complete but I decided to start this project during the peak of my undergrad thesis so I really had no time to spend on it. After graduation I started a new job and had a similarly little spare time. Plus, it's been parked at my dad's place and without it as my mode of transportation it was a pain in the ass to just get over there to work on it.

Secondly, the whole thing started because I got a whole bunch of money all at once and felt like I could afford to rebuild/replace everything! It turns out money evaporates pretty quickly when you start rebuilding heads, rebuilding brakes, buying shiny headers from Tom over at 02again (best thing I've bought for my car so far though!). It gets worse when you don't have many tools to begin with, After that initial bunch of money was gone I ended up stealing wrenches from Sears and scrounging pennies to buy miscellaneous stuff like wire. If I had budgeted the project well I think I could have done the basic MS setup for under $1000. For the basic setup the expensive parts are the MS its self, the wideband O2 sensor, and the fuel pump. Definitely make sure you've got your bases covered on all the parts before you start though. Like someone else mentioned, there's nothing worse than putting the project on hold until some obscure part shows up in the junkyard or on ebay.

Thirdly, I recommend going one step at a time rather than all at once. If I were to do this over again (Which I hope to do at some point knowing what I know now), I would install the MS with all the sensors first then replace spark and fuel one at a time, doing thorough checks at each point. It will make troubleshooting a billion times easier.

Hopefully I didn't discourage you from trying it out, it's a really interesting project and you definitely learn a lot along the way. Good luck!

-Jonathan

[austinmf]

Good info!! Nice write ups and I will need help.

My car has zero zing...it struggles up the rpms and never pulls... it just goes...

SLOWLY...

I have almost everything I need for the build expect the brain, injectors, O2 sensor and fuel pump. Still unsure about COP vs a standard accel coil.

Getting most of Toms stuff and will rebuild the head and go with a 292 cam.

I really could not do as much as fast without the support of this board!

[Harv]

When I did my 145 Volvo, I prepared many of the systems in advance, Like I got my fuel supply mounted and ready to go but just didn't hook it up. Installed my return fuel line, but left it caped off under the hood. Installed the MegaSquirt and relays but only had them controlling the low psi fuel pump that was feeding the webbers. When it came time to actually do the install, it was a matter of removing the webbers and installing the efi manifold.

Fired up on the first crank and I drove it to work the next day.

John