[jetenginedoctor]

Originally Posted by Sizzler

Factory Ford SVO had a EEC-IV ECU that you could buy direct from them. It was intended to piggyback on the existing EEC-IV. It was designed to piggyback and override the programming in your existing ECU. It was basically a fully-functional EEC-IV that was also fully programmable. It could also be used by itself, as a standalone ECU.

The TwEECer R/T is money a lot better spent. The factory EEC-IV engine control strategy isn't difficult to work with if you take the time to read up on it a bit. For $550, you get all the programability you'll ever need in a MAF engine management system, and an almost unlimited CHEAP supply of replacement ECUs should you ever need one. In other words, I can put my hand on a working A9L ECU any day of the week for $100 or less. An SVO-EPEC is rare as hen's teeth, and relying on one for your car to run correctly is a big uh-oh if you actually DRIVE your car more than 100 miles from home.

To port inject a tunnel port, I'd try a spider intake and mount the injectors back a ways from the ports and tubes, giving the sprayed mixture a good chance of getting into the 'flow'. Having the injectors smack bang next to the port isn't as critical as some might tell you.

It's not a matter of being critical, it's a matter of being the smart way to do it. Putting the injectors further upstream from the intake valves increases the effect of port wetting (Tau) and makes tuning transients a huge pain in the ass. Furthermore, the injector fires on a stagnant air column far more than it does a moving column. The "importance" of firing the injector while the intake valve is open is simply not what many arm-chair engineers will try to tell you. Frankly, injector timing makes almost NO difference in performance, and very few tuners (much less OEM calibration engineers) have the equipment or understanding at their disposal to really get much out of manipulation of the injection phase events.

As long as they're in individual intake runners, well on the way to the port, they should work ok.

This really isn't true either. Because the injectors don't/won't/can't always fire into a column of intake charge headed past the intake valve and into the cylinder, there is a certain amount of fuel that will be carried into the plenum due to inlet charge reversion. The more aggressive the cam profile, the greater the charge reversion, especially at low engine speeds. Where this becomes a problem is the fact that you end up with a huge amount of cylinder-to-cylinder "charge robbing" that causes each individual cylinder to have wildly varying air/fuel ratios despite the fact that each has injectors firing the SAME amount of fuel into the inlet port. This will cause terrible idle and drivability issues that can only be tamed (partially) by adding a bunch more fuel to the calibration at those lower engine speeds resulting in fouled plugs, cylinder wall washdown, excessive fuel consumption, excessive emissions, etc. Bottom line, putting the injectors at the far end of the inlet port is simply not a good idea.

But I haven't injected a tunnelport, so I don't know that from actual experience. I have injected an engine where the injectors were a solid 8 inches from the intake/head interface and that seems to work alright.

Good Luck

I'd bet money that you were injecting into the plenum of a single plane 4bbl caburetor style intake manifold, right? Again, for the reasons mentioned above, it is a far better idea to fire the injectors onto the backs of the intake valves.

Brian Kennedy
BMEP Fuel & Tuning