Fuel computers described/explained

[gijoe985]

Alright, I've been trying to learn more about the different options available for fuel computers, piggy backs, and whatnot. I'm going to write some basic statements, that I believe t be true, if I am wrong in any way, please correct me. My primary goal for this post is for me to learn, but hopefully be the time some other people chime in, it will be fairly comprehensive.


Options-

A'pexi AFCs- SAFC I, SAFC II, AFC Neo-
All of these should hook up to any DSM. SAFC has 12 points of tuning, 16 points for the neo. You can also adjust timing with these. Pretty simple. They don't monitor knock. The neo is the newest with some extra options that don't apply to us, like the Vtec control. Some people like the fact that SAFC I uses buttons instead of the single knob on SAFC II. From what I was just reading, the A'pexi piggy back products may be limited to 650cc injectors and lower due to the limit of correction that they can make.

Megasquirt-
I don't even know the models, but I do know that there is a lot of wiring that needs to be done to get this hooked up. I've also read that there are more options with it. If you know what you are doing, you can rival an AEM system for a third the price. MS seems to have some options that allow you to make changes if you added water injection or other features. From what I've seen it seems like a very complete system, I don't know how compatible it is with other vehicles (I know the Apexi stuff could be taken out of a Honda and dropped in a DSM.)

DSMlink-
I'm not even going to go too in depth on this. There is tons out there on it. DSMlink has many many great options for DSM vehicles. It is specific to 1g and 2g cars. So you need the right one and it won't work if you switch gens. I am not certain what you do if you put a 6 bolt in a 2gen. Probably keep the 2g ECU, so 2g dsmlink. So, IMO, if you have a DSM setup that you are wanting to go all the way with, you don't need to move your AFC into another vehicle make, and you aren't making an 8 second car (I just assume you'd need AEM for that, maybe I'm wrong) then DSMlink would probably work great for you.

GM MAF(t)- There are two sizes of GM MAFs, 3" and 3.5". The MAF Translator (MAFT) is a box that converts the signal from the GM output to an output our car can read (Karman Hz). The basic MAFT has 2 adjustments in it. One lets you select the MAF size (3" or 3.5") and the other is used to set your injector size. It is often recommended to use a GM MAF / MAFT in combination with an AFC device to fine tune it. As airflow increases, the GM MAF becomes more and more sensitive to air flow. Also, different piping sizes/shapes before the GM MAF can alter the reading, furthering the need for an AFC device. (from knochgoon24)

AEM- My focus wasn't on stand alone setups, so all I'll say is that I know the AEM system is very complete, can do most anything, but takes some serious tuning to accomplish it. I am not certain if the AEM is made Mitsubishi specific at all, or if their units can be moved from one make to another.



-Alright, I'm sure I left someone out, please give your thoughts on anyone missed.
-If you can correct anything that I have said, or wasn't sure on, I'll make the change to my post.
-Something I could not write about was the ease of installation and the basics of the tuning process with each of these. If any of you have experience installing these or tuning them, I'd love to hear about it.

As for me, all this research began in the attempt to find a system that would work on multiple vehicles to allow me to change fuel trims and timing. I buy and sell vehicles frequently, but want to keep the AFC, so I need something that is versatile. (Hence why DSMlink isn't for me, but I think it is awesome.)

Thanks Everyone!

 

[gijoe985]

Ok, I've been continuing my research since I wrote the above post, and as for my application I think going with SAFC-II is what will work best for me. I think AEM is too costly and too much work if it isn't staying on a car long term. Same with Megasquirt for the too much work. I don't think a GM-MAFt would work on some other vehicles. (Maybe I'm wrong there.) And obviously DSMlink is limited to what vehicles it'd go on.

I decided on the SAFC-II instead of the Neo because of the two setups that can be saved. I like that.

 

[matthewdesigns]

As for me, all this research began in the attempt to find a system that would work on multiple vehicles to allow me to change fuel trims and timing.

I decided on the SAFC-II instead of the Neo because of the two setups that can be saved.

The SAFC does not give you direct control of timing. Timing will change as a side effect of your airflow numbers decreasing as you compensate for larger injectors, but not in any way that's particularly useful. This is not to say that an afc is not a decent tool...it can be. Just don't buy one thinking it will do anything other than make it possible for you to use larger than stock injectors, up the 650's you mentioned.

 

[gijoe985]

The SAFC does not give you direct control of timing. Timing will change as a side effect of your airflow numbers decreasing as you compensate for larger injectors, but not in any way that's particularly useful. This is not to say that an afc is not a decent tool...it can be. Just don't buy one thinking it will do anything other than make it possible for you to use larger than stock injectors, up the 650's you mentioned.

Thanks, I must have gotten confused with all of the reading I've been doing. Does the Neo do timing? Maybe that's it... Or maybe not... But thanks!

 

[dsmfa9nutter]

Ostrich- Works the same way dsmlink does, just $425 cheaper than dsmlink. Has some different little options but all the basic things are there, fuel/timing/limiter/stutterbox/NLTS/injectors/etc.

 

[matthewdesigns]

Does the Neo do timing? Maybe that's it... Or maybe not... But thanks!

None of the Apexi AFC's, to my knowledge, can adjust ignition timing. I'm fairly sure that at least one model can control v-tec actuation on Honda's, so maybe that's the "timing" you read about.

For ignition timing control, you are either going to have to pay for a program like ECMLink which offers a nice GUI and a lot of control or a custom eprom chip which is programmable, or learn how to use an Ostrich emulator with eprom chip, or build MS. MS is probably the one which would allow you the most flexibility with respect to swapping platforms, since the others would be tied in some way or another to our native ecu.

 

[gijoe985]

Yeah, I agree MS has the most flexibility, but it also looks like a lot of work. Not that I am opposed, but if you only own a car for a few months, it's nice to plug and play...