motor swap need help

[kenmosher]

The intank pump can be a restriction ... definitely make sure it's powered and operating or it'd be like sucking thru a collapsed straw.

If the intank pump can be used as sort of a "lift" pump and the bigger pump can pull thru it without major restriction (when both pumps are running), it can work fine that way (I did it before all the nice in tank pumps were available "back in the day" ... provided enough fuel to almost overwhelm the stock pressure regulator).

If the intank is too restrictive, I'd remove it and put in the pickup. Easiest way to tell what's what ...

1. With stock in tank, time how long it takes to pump a measured gallon of fuel.

2. Put the puller pump inline with the in tank and repeat.

3. Time the puller pump by itself

[jmcgrath_22]

Well the harness is in. As far as I know everything is installed and connected properly. I am to the point now where I am sifting wire by wire on the in car portion of the harness, to see what all I need. Unfortunately it looks like just a big pile of wire. I know it's a veg question but could someone give me a brief run down of what all is needed out of this portion of the harness to run the motor. I would like to retain the main functions like gauges but I want to keep everything as simplified as possible. Thank you if advance

[Keller]

It'd be best to have a OEM diagram for the 84/85 cars.

Power to the fuel pump relay is fairly important, but you can work around that.

The ignition wiring will be critical.

There is an oil pressure switch that will not let the car run (will not power the fuel pump beyond the initial prime) until it sees adequate pressure. That may be a stumbling block. The good news is it is integrated as a separate prong on the OEM oil pressure switch, and replacements in the aftermarket are available.

[pfredricks]

How did you handle the Vehicle Speed Sensor (VSS) signals? I don't think they are used for engine controls. I believe that the ECM and VSS simply control the transmission torque converter lock up, i.e. in 3rd or 4th gear above a certain speed and the car gets better fuel economy. But the question I have is do you ground them or leave them open to the ECM?

If you are using the 86-87 ECM you'll need a Intake Air Temperature sensor. Caspers, thankfully, has them.

If you are using the 86-87 C3I module you'll need a adapter for the 84-85 harness to the 86-87 C3I module. Caspers, thankfully, has them.

How about your Mass Air Flow (MAF) sensor? If you are using the 86-87 ECM you'll need an 86-87 MAF in which good ones are hard to come by. I've converted to the LT1 MAF and a box to convert the signals expected by the ECM.

Are you using a narrow band or wide band O2 sensor?

Thanks.

[kenmosher]

Originally Posted by pfredricks

How did you handle the Vehicle Speed Sensor (VSS) signals? I don't think they are used for engine controls. I believe that the ECM and VSS simply control the transmission torque converter lock up, i.e. in 3rd or 4th gear above a certain speed and the car gets better fuel economy. But the question I have is do you ground them or leave them open to the ECM?

Yup, although some of the snazzy new chips may use the Gear Switch Signals (NOT the VSS) to alter settings on the fly (like the Commander and TurboTweak? I'm not sure about that, but it's worth researching). You'll need the actual VSS ... it's pretty important.

As far as the "ground them" issue for the gear signal switches, you can just leave them open if you're not using them to do some sort of programming in the ECU (assuming fancy chip or aftermarket ECU). Just be aware you won't get any TCC lockup with a standard chip.

How about your Mass Air Flow (MAF) sensor? If you are using the 86-87 ECM you'll need an 86-87 MAF in which good ones are hard to come by. I've converted to the LT1 MAF and a box to convert the signals expected by the ECM.

The translator would definitely be the way to go.

Are you using a narrow band or wide band O2 sensor?

The stock style computer will have to have the narrow band signal (even if you use a wide band controller, you'll need to hook up the narrow band output to the ECU). Disregard if using an aftermarket ECU with wideband capability.

Thanks.[/quote]