What should the reading be on both injection wires (black and black and pink) when disconnected from the injector and ignition on?

I'm still very new at this and taking things one step at a time.

 

Injector windings would usually read between 12 and 16 ohms.

 

Except that's the resistance reading on the injector connectors themselves. I think he's asking about reading on the harness side while they're unplugged.

And as far as I know, you won't get any readings on that side except during the milli-second one is getting pulsed. THat's why noid lights were created and used.

 

If I am getting readings on both sides, would it be an indicator that there might be a short, or something may be hooked up incorrectly?

 

With the injector unplugged, you should have ignition voltage on one and a pulsed ground on the other. This means that with the engine off, you should not have any kind of voltage or continuity to ground, HOWEVER, if the other 7 injectors are plugged in, you will get voltage backfed into the circuit, since ignition voltage will travel to the injector windings and out the ground side. You will notice that if you ground the ground wire for one injector, the other injectors will also pulse, since the grounds all all tied together (batch fire fuel injection system).

 

That makes perfect sense. So, if I unplug all the injectors there should be 0 reading on the ground side of the plug? I'll give it a try.

Now, while I have you.... I am putting this motor into an older model and don't have any smog concerns. It is a 305 and I was going to run 2 1/4" exhaust pipes. Seem OK? What else do I need to know about TPI motors and exhaust?

Thanks again,

Ken

 

Two 2.25" pipes merged into a 2.5" single over the axle will be good for a 305.

As far as what else to know, it would be easier to to answer specific questions then try to type everyting I can think of.

 

I'd love to ask a few questions, and I really appreciate your help.

My plan is to run dual exhaust, one off each header with a muffler on each (flow master probably). The muffler people mentioned a cross over. Anything specifically I should know or require?

I have the O2 sensor mounted on the collector on long headers. Will this distance cause me any problems.... if so, would a heated sensor help.

 

Heated sensors are almost required with headers. I have seen one-wire sensors work on a few shorty style headers, but I wouldn't even try on Longtubes.
Here is how to install a 3-wire heated sensor http://sethirdgen.org/HO2S.htm

You can also use a 4-wire by putting the 4th wire to ground as well.

Duals are a tight squeeze in these cars, but it has been done before.

 

Big hello again to GMTech. Miss seeing you around.

I'm guessing it's not going on a thirdgen, but for h-pipe discussions, pop over to the exhaust board and search in there there have been a few good threads that covered the info I think you're looking for.

 

Thanks! Always glad to help out.

 

I'll check out the "H pipe" thread. You are right, it is going into a 69 impala which is smog exempt. I bought a 91 Z28 convertible and became enamored of the TPI. My thinking was that I am of average intelligence so going to computer controlled fuel injection won't be that big a deal. It is. Now, I am about 7/8th done with this project (mechanically speaking) and want it done.... so I can get the z28 going. These final throws seem to be the most difficult. Once I have the exhaust on, I'm taking this bad boy to a mechanic and getting it finalized.

Thanks again for all your input.

Ken