Thread: Crazy EFI idea?

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I mentioned on Dave's FAST EFI thread that I was interested in getting into EFI. The new self tuning ECU's look like they will give someone like me a chance since I don't have access to a dyno anywhere close.

My latest project is going to have a 383. I have a couple of old TPI units laying around, but the general consensus is that without a lot of expensive high flow parts, a TPI will severely choke a 383 above 4000 RPM. It will make a ton of low speed torque, though.

Over the last few years I have managed to get a decent machine shop set up in my shop. I'm also wanting to get into aluminum casting. Hopefully I'll get that done this winter. I can build what I'm about to describe without spending a lot of money, just time.

The other day I was looking at the TPI base manifolds and it dawned on me that they look sort of like a cross ram manifold. I started thinking about converting one by fabricating 4 two barrel throttle bodies to go in place of the TPI runners. The TB's would extend out more or less horizontal over the valve covers with stacks. The stacks could either be capped with long narrow air cleaners or a tubular log that connected to cold air induction forward of the radiator support.

I think the injectors can be turned 180* so that the wire connectors are pointed toward the middle of the engine and the stock fuel rails can be reused. A decorative cover panel would hide the wires and the old EGR valve location(I wouldn't be using the EGR valve). The old EGR passage connects all the runners together and I think that it would serve as a vacuum balance tube.

Another crazy idea is to add an idle air valve to the old EGR location. Theoretically the common EGR passage would allow idle air to bypass the throttle blades. The EGR passage would be blocked off on the exhaust side. A tube would supply the IAC with filtered air from above one of the throttle blades. Sounds like it would work anyhow.

Here is a pic of the TPI base. It sure looks like a cross ram manifold to me.



It would be similar in concept to this.



You could also do something similar to this easier than my original idea using junkyard throttle bodies. This would be a natural for cold air induction and the stock (from whatever?) TB's would already have IAC.



The TPI base can be opened up pretty easy for better flow and the throttle bodies could be fabbed any to any size so it should flow better than a stock TPI. Yeah, it's a lot of work, but it sounds like an interesting project to me. It would look cool too.

OK, so talk me out of it. Any potential problems?