MPEFI, need questions answered

As of a few weeks ago I was planning on just yanking the 170 and dumping in a 200. After some cost checking I've decided to keep the 170 but switch to a D7 head.

And instead of the Tempo EFI as originally planned I'm looking at going to multiport. (The main reason I was first looking at the Tempo route was the bolt on factor, now that the car is down for a while and I'm doing a head so I figured on multiport.)

What I'm looking at doing is 6 injectors and three throttle bodies. Now, I realize I may be opening a can of worms by wanting three throttle bodies as it's supposedly a "carb method" of thinking and doesn't apply to efi. However to me (and I'll be the first to admit I'm no authority on this issue) it would seem like three smaller throttle bodies spread across the log would distribute the air more evenly to the cylinders as opposed to one larger throtle body centered on the log. More even air distribution coupled with far more even fuel distribution due to each cylinder having its own injector should lead to a better atomization reaching each cylinder resulting in better wet point distribution (IIRC stock setup is around 35% WPD), better WPD means timing doesn't have to be as radical which leads to better reliability, efficiency and power.

So with that in mind, my questions are this:

1) What pound injectors should I use? (right now I'm looking at 19lb injectors for a 5.0 from CJ Pony Parts)

2) What should I use for the throttle bodies? (I'd prefer something from a salvage yard due to cost)

3) This is a shot in the dark, but if I were to get 2 more 1100 carbs, disassemble them, junk stuff such as the float, ball checks, choke assembly, etc and modify/sleeve the venturi so it's just a straight shot for the air could I use the 1100s as the throttle bodies?

Why make it even harder? One throttle body gives you IAC, TPS. Presuming you want everyday driveability and tractability out of this engine, then a single unit will be preferable.

wouldn't more TBs give you more air coming into the engine though?

although, technically i guess if you were using a Speed Density system as opposed to a MAF, you could just open up several holes in the log, mount a throttle plate to it, plumb them to the filter, and use one TB as long as you factored in how much the other holes would add to the air flow of the engine

8) you probably want to use tempo efi throttle bodies as they have the throttle position sensor already installed. three of them would work just fine, though i would hook up only one tps sensor. another option is to open up the ends of the log as though you were going to use three carbs, and build a manifold that runs from each of the openings to a single throttle body from say a 5.0 mustang. those are a 55mm opening and have the iac motor as well as the tps built in.

I wish I had a nickel for everytime someone comes up with the multiple TB setup on their engines. The most famous stock setup would have to be the 4AGE, but even then enthusiasts swap them out for the DCOE injection bodies.

The 170 is not a high strung engine with pedigree geometry. It needs all the help it can get from better breathing and individual TBs won't provide that as they are more suited to high reving lumps where the VE would otherwise tail off and reversion becomes a secondary consideration.

A static regain plenum mated to a single throtlle body will be your best solution, both for breathing and stable idle. The plenum is a cushion box and not only serves to raise static pressure and reduce velocity pressure of the incoming air, it also allows the higher pressure wave coming up the runner from the closing intake valve to shunt air into the runner of the opening inlet valve.

170 cubes is not a lot of power production, especially in a wheezer, but injection should give it a boost over carby, if only for the better fueling ratios. Depending on the engine code the stock gross power is circa 105hp at 4400 rpm. So if you were able to push that to say 116hp your injectors would be ~= 13lb.

50mm TB, 60mm charge pipe, 1700 cc plenum. The intake runners willl have a harmonic length of 2400mm , but space being what it is you need to reduce greatrr than the 5th harmonic which means you won't get much purchase out rarefaction. = make them as long as feasible.