Easy to Learn EFI?

[Orange65]

I currently have a MS2 that I am planning on using on my 489 that I am building. BUT it looks like time is going to be a problem. I want to do Drag Week this year, but I have some new obligations that are going to take up my time for the most part. So learning the MS and setting it up is out of the question from what I have seen of the installation and learning curve.

So- what EFI system (port injected) is the easiest to install and setup? The application is a 650 HP NA BBC. I would not mind a TB injection unit, but they seem to be limited to 600 HP or less. Cost is a minor concern if I go this way. I already have an EFI ready intake. I am concerned about the amount of time it will take to get the system operating correctly once it is installed as well. Any thoughts on Accel, Holley, FAST, or even the upper level Big Stuff (or any others, for that matter)?

[dieselgeek]

I currently have a MS2 that I am planning on using on my 489 that I am building. BUT it looks like time is going to be a problem. I want to do Drag Week this year, but I have some new obligations that are going to take up my time for the most part. So learning the MS and setting it up is out of the question from what I have seen of the installation and learning curve.

So- what EFI system (port injected) is the easiest to install and setup? The application is a 650 HP NA BBC. I would not mind a TB injection unit, but they seem to be limited to 600 HP or less. Cost is a minor concern if I go this way. I already have an EFI ready intake. I am concerned about the amount of time it will take to get the system operating correctly once it is installed as well. Any thoughts on Accel, Holley, FAST, or even the upper level Big Stuff (or any others, for that matter)?

The learning curve is going to be the same on any system you choose to run.

Your best bet is to get help from a friend who's done it before, then you can pick it up as you go along yet still get the car done on time.
Also, I know you see a lot of "BigStuff's" on drag cars, but it's not an "upper level" system by any stretch. It's the last one in your list I'd recommend. FAST XFI is a pretty easy interface to use (but the tuning interface sucks - it only offers a spreadsheet view, same as BS3, DFI, Holley).

Where do you live? maybe we can help you find a megasquirt guy locally.

[BBR]

My advice?

Install the MS while you still have a carb on it, get used to fiddling with it, log some data and use that as a starting point for your efi mapping.

It's not hard to do. It does take time and having a running car already is a MAJOR plus.

[dieselgeek]

Ya know what? BBR is right. Do it in baby steps (which the MS lets you do easily) and you will have no problem. Like squirrel is doing!

First, just hook it up on the car and try to get a clean tach signal. Then hook up the Temp sensors, MAP sensor. TPS can wait until later, it's not that important.

Then once you're comfortable looking at the data, make the FUEL switch only. Leave your ignition alone and just use the "Tach Output" of your ignition box to feed the "tach input" on the Megasquirt. Tuning "Fuel Only" is a breeze, honestly.

Once you have the fuel down, then migrate the ignition (it's just a few wires) and test it out.

That really has to be the best method to learn EFI. There's some good reading on DIYautotune.com's website about this approach too. Plus there are a ton of us here who would be glad to help you out,
-Scott

[TheSilverBuick]

I'd bolt on the EFI intake, put a square bore carb on it and run it looking at what the AFR's are doing at certain load points across the rpm range (off throttle, cruise and WOT) then you can either set up the MS AFR table to match those AFR's or you can build a VE table. Tuning from way rich to lean is easier than starting way lean and trying to richen it up.

On my TBI'd T-bird I've been playing with the Self-Tuning function, which requires the AFR target table to be set up (it's like 12 or 16 cells on the MS1?) and it works pretty good once I let it have free range. I had a few lean spots on the fuel table that it would add fuel until it maxed out at like 50% greater than it was set for. Thought I'd let it have free range and changed 50% to 5000% and it's been good since.

[Orange65]

The learning curve is going to be the same on any system you choose to run.

Your best bet is to get help from a friend who's done it before, then you can pick it up as you go along yet still get the car done on time.
Also, I know you see a lot of "BigStuff's" on drag cars, but it's not an "upper level" system by any stretch. It's the last one in your list I'd recommend. FAST XFI is a pretty easy interface to use (but the tuning interface sucks - it only offers a spreadsheet view, same as BS3, DFI, Holley).

Where do you live? maybe we can help you find a megasquirt guy locally.

Two assumptions made here- I have a friend and I live near someone....

I live near Tupelo, MS. I just moved here and have not made any car friends. The carb to EFI migration that BBR mentioned sounds promising. I had not thought of that. After reading a lot on the FAST EFI this morning, it looks like a good system but the $4400 price tag is a bit steep. If I could start out with a baseline once it is installed, that would help alot. Is closed loop tuning part of MS2?

[dieselgeek]

Two assumptions made here- I have a friend and I live near someone....

I live near Tupelo, MS. I just moved here and have not made any car friends. The carb to EFI migration that BBR mentioned sounds promising. I had not thought of that. After reading a lot on the FAST EFI this morning, it looks like a good system but the $4400 price tag is a bit steep. If I could start out with a baseline once it is installed, that would help alot. Is closed loop tuning part of MS2?

Yes, closed loop tuning is part of MS. Although, I'll say that once you get to the point you are ready to tune, there's really no fear - you will 90% likely want to do the tuning by hand because it's super simple to do, and despite what you might hear or think or read online, it's nearly impossible to screw up an engine from a tuning mistake.

We could find you a baseline tune or build one, to get you started.

Is your MS2 assembled or does it require assembly?

[TheSilverBuick]

Closed loop is an option, that I'm guessing most use. I run open loop on my Skylark, but have been running closed loop on my T-bird.

I was driving my Skylark the same day I fired it up with EFI. Sure the tune was a bit rough at first, but after about a week the drivability was good for normal driving. With my experience with it now I think I could get good drivability from it in a couple drives rather than a week, and that's me doing the work not letting the MS autotune do it.

The method I use now is get the idle happy and steady, AFR's may or may not read well depending on how big the cam is (mine reads fine). Then get the free revving smooth and the holding higher rpm's (~3,000+) in neutral/park. From there you can "guesstimate what the fuel map should look like when driving. Just make the fuel map have more fuel in it than the free revving and unloaded higher rpms, ie make the fuel map slope upwards as load increase (vacuum drops). Then do some low/normal load cruising. Get it happy with AFR's there, either using the Autotune, datalogging and changing later or a friend in the passenger seat. Then once normal drivability is good and you are happy with the AFR numbers, see where you haven't really touched the VE table (at high load and high rpm) and add a crap ton more fuel to those areas than you had on the normal driving part of the table. Then go do some romping on the throttle in various gears and see how your AFR's look. Mine always seem to be in the 9-10:1 range when I do this, then I back out some fuel and try again. You'll get a feel for how much "X" fuel you have to take out of the VE table to change the AFR "Y" amount. There is no set number because it depends on a dozen factors, like what injectors you are using, your "required fuel" setting, engine efficiency, etc. It's pretty straight forward, IMO. At idle and in neutral I think it's about impossible for the tune to hurt the engine (can't melt pistons, etc. with no load can you?), then with the regular driving part, short of pinging from too much compression and not enough octane, then running lean, it's pretty hard to hurt an engine. That's why I run them fat and lean them out. WOT is the only worry on being too lean (carb likewise), but it's easy to extrapolate the VE table to make sure you don't go lean if you have a good driving around set up.

I ran my Buick 455 with a Q-jet and 4-pin HEI first to make sure the engine was good to go before I swapped on the EFI. Now I'm comfortable enough with the EFI to actually fire up a new/rebuilt engine with it. I have 2 cars/engines under my belt, one with an MS2 and one with MS1.

[Orange65]

I bought mine assembled. I can solder and have some electronics experience, but I had a few bucks.... I am looking at getting the expansion board that has the relays and fuses on it. I would mount that in the engine compartment and the MS2 in the cab. That should simplify wiring some.

What type of injectors do I need? Saturated or peak and hold? I am looking at RC Engineering injectors. At 80% duty cycle, I need 51+ lb/ hr out of the injectors. I already know that I have to use resistors in line with low impedance injectors...

[dieselgeek]

I bought mine assembled. I can solder and have some electronics experience, but I had a few bucks.... I am looking at getting the expansion board that has the relays and fuses on it. I would mount that in the engine compartment and the MS2 in the cab. That should simplify wiring some.

What type of injectors do I need? Saturated or peak and hold? I am looking at RC Engineering injectors. At 80% duty cycle, I need 51+ lb/ hr out of the injectors. I already know that I have to use resistors in line with low impedance injectors...

You don't need injector resistors if you have a v3.0 or v3.57 circuit board. Is your board Blue? I hate injector resistors!

Also, you can get injectors in high impedance (low current = lower noise) at the size you need. I'd try to get those if you can.

[Orange65]

I don't remember the version of the MS2 that I have. I will look this weekend.

[dieselgeek]

I don't remember the version of the MS2 that I have. I will look this weekend.

It's not really the MS version (1, 2, or 3) it's the Printed Circuit Board it's all mounted on. Look in Stiney's thread, the board is Blue. The Blue boards (3.2 and 3.57) both have "high current injector drivers" built in. Thus no need for resistors. But, if you go with high impedance injectors, which you should be able to find pretty easily, it doesn't really matter what PCB you have.

[TheSilverBuick]

I run low impedance injectors on my Thunderbird's TBI (2 85 lb/hr) with a 3.00 board and MS1 processor. There is a setting in the Engine Constants for pulse width modulation to lower the voltage/current going through them. No resistors necessary.

[dieselgeek]

I run low impedance injectors on my Thunderbird's TBI (2 85 lb/hr) with a 3.00 board and MS1 processor. There is a setting in the Engine Constants for pulse width modulation to lower the voltage/current going through them. No resistors necessary.

Caution, that's only do-able because you have a small number of injectors. Can't be done with 8 MPI injectors unless you have the circuit board upgrades to support it.

[TheSilverBuick]

Caution, that's only do-able because you have a small number of injectors. Can't be done with 8 MPI injectors unless you have the circuit board upgrades to support it.

Why wouldn't it work with 8 injectors on a 3.0 board? Isn't running a set of 4 low impedance injectors per bank easier on it than a single low impedance injector? With the injectors tied in parallel the resistance would be the same as a single wouldn't it? Might require a tad more current because the 4 paths instead of one, but more than a set of 4 high impedance injectors?