Thread: EFI Options

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It's a separate part, not for highway use and all that. I think they use the brain out of a STS and take out all the whistles and bells and leave the engine management system then tweak it. It comes with generic program to get you going then you can tune to your specific needs.
Ken

I learned a few things today talking to Erik at the House of Boost, a tune/install shop in the KC area that generally works on outrageous HP engines, like an 1100 RWHP Mustang - crazy fast, but still streetable. These are my interpretations, and my limited understanding after an hour with the guys doing the installations.

It seems that 600HP is the real break point - below you can use what you want from TBI to direct port injection, and from batch fire to individual fired injectors. The real key to having to spend the extra money to fire injectors individually (more ECU) is that the big injectors that are needed to flow to the >600HP engines generally can't turn down far enough to give good control at idle - batch firing (groups of four, generally) pushes the engine too rich at idle so individual firing is the answer, or even going to multiple injectors per cylinder, and turning some off at idle.

For an engine in the <600HP range the ECU can control the A/F ratio across the load range in batch fire mode, or even using TBI. In fact, there are said to be some advantages to having the injectors farther away from the head, to gain the cooling effect of the fuel in the air which tends to increase the density of the charge. It really comes down to the "look" that is desired for the "lower" HP applications (I'm still having trouble with a 425HP engine being "lower" HP One can go "trick" and eliminate the distributor, firing hidden coil packs from the ECU, and an "in your face" throttle body and air cleaner setup; or keep a traditional distributor/MSD box for timing, and let the ECU handle only the A/F ratio, hiding the TB under a traditional air cleaner, looking like a four barrel carb to the casual observer. The beauty of the better aftermarket ECU's is the A/F ratio map that lets you tune point by point, for all power conditions, viewable via serial port on a laptop. The ugly is the ECU cost

Not sure what I will end up with yet, but I feel I have a little better understanding of the basics, and that I don't "need" direct port, individually controlled injectors for a "little" 347

I don't know Ford systems, but for GM it's really hard to beat a GM computer IMHO. OEMs have spent millions on developement, so why not take advantage of that? advantages are: lower cost and able to learn your setup, whereas most aftermarket systems only know what you teach them from day one. some OEM systems have been hacked wile many have not, so of course you'd look for a well know OBD1 system. I tried to post a you-tube link here a day or two ago to show what can be done with mostly stock components and some fabrication time, but the moderators apparently haven't "approved" my post yet. . bottom line is not to over-think it. EFI isn't as hard as we tend to make it.

lotsa

The 600hp break point is right at the max a stock Ford smallblock will handle without splitting down the middle. I'll never be shooting for that unless I buy an aftermarket HD block. I build to please me and not a dyno with a run to Bremerton for an afternoon of T&T seeing if the car is running better. Thirty miles over, thirty back, four bucks for bridge toll and a 12mpg average including racing. Cheap and the most fun you can have with your pants up.

Originally Posted by lotsatoys

I don't know Ford systems, but for GM it's really hard to beat a GM computer IMHO. OEMs have spent millions on developement, so why not take advantage of that? advantages are: lower cost and able to learn your setup, whereas most aftermarket systems only know what you teach them from day one. some OEM systems have been hacked wile many have not, so of course you'd look for a well know OBD1 system. I tried to post a you-tube link here a day or two ago to show what can be done with mostly stock components and some fabrication time, but the moderators apparently haven't "approved" my post yet. . bottom line is not to over-think it. EFI isn't as hard as we tend to make it.

lotsa

From what I have seen so far I cannot disagree, and that is why I asked Ken if his GM computer could accept an assigned firing order. The problem with Ford is the break to modular motors in '95/'96 which means you are looking at a 15 year old computer. Another thing I have against the OEM units is the lack of a serial or USB port, so you must rely on finding someone with a OBD1 or 2 to help get to the source of any problems. I cannot argue with your logic on the learning mode, and the millions spent on R&D, nor the "don't over think it" advice. It is not rocket science.

Nor is it brain surgery. Crack the 15 yo Ford ecm and clean the epoxy off the contacts and it is ready for the interface with the computer. Not that you would need it for 425 hp. An Obd 1 or 2 reader isn't expensive as a tool in the shop. Probably a lot less than some of the computers in question.

Only problem with EFI and some cam selections is idle quality and that can be solved with a hotrodder work around add on to the IAC servo base. If I decide on more power then I need to recalibrate the MAF sensor and plug in bigger injectors with an adjustable fuel pressure regulator. Next bump would include a bigger fuel pump, higher rated press reg, bigger injectors and new plumbing for the fuel lines as the stockers won't handle the pressure.

Were I rodding a mod motor, I might consider that ecm although they will put out incredible hp with a stand alone dis and a sheet metal intake with a 750+ carb.

end of page one. my you tube link "appeared" finally.

lotsa

Nice vid. Like it a lot.

Originally Posted by lotsatoys

end of page one. my you tube link "appeared" finally.

lotsa

Your You Tube link was there yesterday, I watched it, very nice work by the way!!

Mike

Originally Posted by w2zero

Nor is it brain surgery. Crack the 15 yo Ford ecm and clean the epoxy off the contacts and it is ready for the interface with the computer. Not that you would need it for 425 hp. An Obd 1 or 2 reader isn't expensive as a tool in the shop. Probably a lot less than some of the computers in question....

w2zero,
I'm interested in your comment about interface to a computer being so easy. Is the contact wiring that is required documented on the Ford forums somewhere?

I'm interested in that information also. I mean shucks, us GM guys just plug into the diagnostic port that comes with the car. it must be a Ford thing

lotsa

I'll have to do some digging in my favorites. That will be fun with the utter lack of organization there.

Well that was less than fruitful. I did find this on google though. It wasn't available back when I was looking before. http://v8tvshow.com/content/view/104/28/

What I was referring to before was a bunch of engineering students that had come up with a site that had freeware to do the trick. Could they be behind this Tweaker program? Damned if I know but then it has been about ten years since I was digging into this.