jnman

Guys, first let me say that my car is pretty much stock and everything works now. The plan is to remove all the smog stuff and all unnecessary clutter, while retaining the ac, heater and cooling fan functionality. Also want the stock gauges in the dash to work. Just trying to clean up the engine compartment up a bit.
I started disconnecting things under the hood and my question is what to do with all the extra wires & vacuum lines. There is 3 or 4 electrical connections going to the carb alone. The new carb (Edelbrock) only has an electric choke. What is the best way to handle this, I really don't want to start cutting up the wiring harness.
Looks like to me a lot of the extra vacuum lines have to do with the smog and heater controls. I know when the smog stuff comes out I will loose a lot of them, but I'm trying to figure out which ones I have to keep, so that the heater works properly.
Last question (for now LOL), my LG4 has a mechanical fuel pump, so I'm guessing there is no electric pump in the tank. Is this correct?
THANKS in advance for any help!!!!!

Damon

You can keep everything functional. Including all the HVAC stuff.

Carb you use the old choke heater wire to power the new choke. The rest you leave unplugged.

Distributor and coil gets swapped out (non-computer controlled large cap HEI is the usual go-to solution). You take the 2 wires from the vehicle wiring harness to your old coil connector (87 should have small cap distributor with remote coil), snip off that connector, and extend the wires over to the BATT and TACH connectors on the large cap HEI. Big pink wires goes to BATT, smaller white wire goes to TACH.

Oil pressure gague and temp gague each have their own senders/wires that just run the gagues- no connection to or through the ECM. Temp sender is on the side of the driver's cylinder head between plugs #1 & #3. Oil pressure sender is screwed into the block just above the oil filter boss.

HVAC requires a vacuum line to work the servos under the dash to direct where the air comes out. That vacuum connector is somewhere near the rear of the intake, pass. side. It goes through a check valve and then splits in 2 directions- one line to the vacuum reservoir in the driver's inner fender, up near the front and the other is a hardline that follows the main wiring harness up through the firewall to the HVAC controls on the dash. Leave all those vacuum lines in place and HVAC controls will work normally.

A/C and the electrical plugs going to it have nothing to do with the ECM- just plug them back on the compressor where they normally go and A/C will work as normal.

PCV valve and power brake booster are your other required vacuum lines, in addition to a vacuum line to the vacuum advance canister on your new (non-computer controlled) distributor. That's it.

Your 87 should have an electrical "helper" pump in the tank already. All V8s got them around 1985. It should not be relied on as the sole source of supplying fuel to your new engine. Either put a mechanical pump on the block, like your car has now or use a proper electrical fule pump with a return-style regulator (Mallory 4309). Personally, I would very much try to use a mechanical pump again. Much simpler that way.

The only thing that won't work when you're done is the lockup function of the torque converter. That you need to buy an aftermarket kit to activate it or rig up your own switch to activate lockup. Not recommended to run without it, but I have many times- just don't lug it in overdrive at too low a speed for any significant period of time.

That's pretty much the highlights.

jnman

THANKS Damon for the reply! This is going to help!

five7kid

iTrader: (14)

Why not keep the q-jet on it? A highly superior system to an Edelbrock carb.

jnman

five7kid, the Edelbrock is new and price was right. The q-jet has been a good carb but will need a rebuild, something that I'm not sure I can do.

The main reason again for swapping it out is that I'm trying to clean up under the hood. On that note, it there any way too get rid of the un-used wiring, without cutting up the harness up?

Damon, you said that there may be a helper fuel pump in my tank. My question is if it happens to go out in the future, will a after market electric fuel pump pull thru the old one?

ZZ3 Z28

I dumped the LG4 in the '90s and I'm still cleaning up the wiring under the hood. It's a never ending battle and you'll always seem to find something that can be done better. If and when you add something like a new electric fan assembly, you'll be wanting to make the wiring look like it came from the factory.

Damon

Generally speaking, a dead in-tank pump is NOT something you want to be trying to suck fuel through with another pump upstream. Even a straight piece of tubing is greatly preferable. But if you have that issue, you have to drop the tank to deal with it anyway. So..... you know.....

Understood why you are asking.

five7kid

iTrader: (14)

Okay, so the price was right on the Edelbrock. Did you add up all the costs?

The computer carb distributor will not work right with the Edelbrock. You need a vacuum/mechanical advance distributor. You can get a cheap coil-in-cap HEI for about $60. One you can depend on will cost you about $150.

The throttle valve cable requires a specific geometry to avoid burning up the transmission. A bracket that attaches to the Edelbrock carb throttle arm is available. Don't leave home without it.

The computer provided the torque converter clutch lockup function. With the Edelbrock, the computer will be braindead. Lockup kits are available to avoid burning up the transmission. Don't leave home without one.

The best thing you can say about an Edelbrock carb is they are cheap. Until you add up all the costs, that is. You're spending, what, $3k on this engine? Why top it off by going cheap?

Well, I suppose you could also say Edelbrock carbs are shiny...

It is possible to clean up the appearance of a CC carb engine. Rerouting wires and hoses isn't that hard. But, I'm a function-over-form guy, so I'm sure that taints my recommendations.

Having said all that, it's your car, and your money, so do as you like.

jnman

five7kid, THANKS for the comments. I knew when I started this project I was going to spend some money and have some questions.

As for the distributor differences, I already have an MSD 8360 Pro-Billet Ready-to-Run Distributor with a Blaster 2 coil to cover ignition issues.

Will order TCI 700R4 vacuum Lock-Up Wiring Kits (376600) for the Trans. lock up issue. I will also pick up the Jet bracket for the TV cable.


Damon, THANKS for the answer on the tank question. Guess I'll leave things as they are in the tank, and deal with it down the road if and when goes out. At this time I will be putting a Holley electric & regulator.


Again THANKS for answering the questions