Researching DIYEFI

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alucardx
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Researching DIYEFI

Post by alucardx »

I'm thinking seriously about building an EFI system for my 1974 Chevy 3/4 ton 4x4 with a 350. I really like the idea of having control of everything in the system, unlike what you get from manufacturers of other systems. I've been browsing around the DIYEFI site and forum and from what it looks like the site is mostly about the developement of the system and software and doesn't include much how to about what parts to use(of course I just may not have found that info if it does exist). What is a good resource for building an EFI system from scratch so that I can control it using FreeEMS? I was thinking about trying to scrounge up injectors and coils from a GM LS engine and the figuring out what sensors I need from there.

I know this is a total noob question but everyone has got to start somewere.

Thanks
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Fred
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Re: Researching DIYEFI

Post by Fred »

There is nothing about which parts to use because the goal is to be able to use any parts at all.

LS coils are good. Injectors should flow 20% more than you need, and not much more. Maybe CC/min = hp for your 8 cyl. So 330 or 440 or 550 cc/min max?

Inject at the ports with an EFI manifold, or build your own.

Get a couple of Spartans from Alan here: http://14point7.com

Get a Jaguar from Andy here: viewtopic.php?f=27&t=2176

But read this first: viewtopic.php?f=41&t=1699

Decide if you're still up for it, it's NOT ready for "users" yet, you NEED some technical competence.

If so: Wire up the coils pseudo wasted style and run 4 injections per bank with two banks.

Fred.
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alucardx
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Re: Researching DIYEFI

Post by alucardx »

I'll think this over a bit more. I'm pretty technical, though not as experienced with electroncs as I'd like to be. That was the other reason this appealed to me was getting more into electronics than I currently am. I am a system admin by day and a motorhead in my [not_so]spare time. I want to do something different with my truck and I also want to use Free Software in doing it.

So right now this system is not a sequential injection system at all, just banked?

Also, this might seem like a dumb question but is this a Mass airflow setup or a speed-density type setup? I might not have my terminology completely correct there so if you need me to clarify my question, just let me know.
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Fred
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Re: Researching DIYEFI

Post by Fred »

It supports sequential on up to 6 cylinders (with no ignition), or by using Sean's XG BB code which means you get NO support from anyone but him. What THAT means is that you effectively get no support at all, because even I find it hard to get hold of him these days :-p Read this to understand: viewtopic.php?f=54&t=1084 I suggested banked to you because of your cylinder count and likely specific power levels.

As for MAF, MAP/SD and TPS/AN, all are supported, but you'd be crazy not to use MAP/Speed Density unless you have a wild cam, in which case an AN/SD blend would be good.

Fred.
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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