Any problems in dropping an 86na engine in an 83?
 

I'm picking up a fresh 86 na engine to drop in y 83 na. My engine is good with 89000 miles but the new one has a aftermarket cam, new belts, seals, clutch, water pump and more. Will the 86 motor bolt right in or do I need to swap things over? Also mine is not power steering and the 86 is. I don't want powersteering. Any problems there?

How much of the 86 engine are you getting?

The major difference is the fuel rail. You will want to take your fuel rail off the 83 engine (don't disconnect the hoses) and swing it up out of the way then put it back on the 86 engine. Reason: The hoses from/to the fuel tank connect differently.

I've found that the newer temp sender for the dash temp gauge uses the same resistance scale so you can hook the old single wire to the two pin sender. One of the pins is an on/off for the 86 dash idiot light so you will need to try both to get the right one.

The oil filler and breather has a larger hole on the bottom than the one off of the 83 so be sure to get the one that comes with the engine.

As to the power steering mount on the bottom of the engine: Just leave it on till you redo the counter balance shaft seals. You have to pull the back or engine side of the belt covers to get to the bolts.

If the 86 engine comes with the steel tubing exhaust be warned that this cracks in the base of the Y on the 1-4 section. I had to go back and use the cast iron headers because of this.

Note that the AFS (yes it is a Sensor as it does not meter or control the intake air) for the 86 uses a different base voltage than the 83. You can't use this on the 83. Now if you wanted to take the time and transfer the DME and AFS and the harness and a couple of other DME items over it would be to your long term benefit.

You will also need to use the polyrib belt pully off of the 83 as it has one less rib than the 86. You could use the alternator off of the 86 with just a minor bit of rewire. Think it has about 20 some odd more amps.

If you want to remove the 86's power steering pully then you will need a really big breaker bar as the bolt going into the crank is one tough MF!

I'm getting the ENTIRE engine and clutch assembly putting a lightweight flywheel on it. Dropping it in and slpping the supercharger on it.

"As to the power steering mount on the bottom of the engine: Just leave it on till you redo the counter balance shaft seals. You have to pull the back or engine side of the belt covers to get to the bolts."

"Note that the AFS (yes it is a Sensor as it does not meter or control the intake air) for the 86 uses a different base voltage than the 83. You can't use this on the 83. Now if you wanted to take the time and transfer the DME and AFS and the harness and a couple of other DME items over it would be to your long term benefit. "

Can you explain these a little more. Are you saying the 86 engine wont work without changing the dme or????? I Don't want any of the PS stuf installed either. Ahhhhhh......why can't this be easy???

It is easy. Don't use the 86 AFS. Don't use the 86 fuel rail.

Change the clutch disk to a spring center if it's not already.

Use the oil filler from the 86.

Change the font crank polyrib pulley (three small bolts) and leave the power steering pully on till you have to change the front seals.

Figure out which of the two pins on the gauge sender is correct.

Be sure to remove the speed and reference sensors BEFORE you pull the engine. Use the 83's bracket to reinstall.

Use the motor mount and AC/alternator brackets from the 83 engine. You have to use the same polyrib belt.

Watch out for a cracked steel tubing header.

These are not complex things. All of this is part of pulling and replacing an engine. You have to do these things anyway -- do them right.

WAIT! doesn't the 86 engine have the auxilary air regular deleted from the injection system? I could be wrong but that would be a very serious problem if you are using an 83 brain still. :confused: But updating to the 86 brain could be to your advantage in case you ever wanted to add a performance chip later.

As for the fuel rail, it can remain the same from what I heard. If the lines are long enough to run from the middle of the firewall on the 83 (85.5-on ran the fuel lines through the right front fender to the fuel rail) than you don't have to worry about changing the rail. I am not sure about sensors though.. guys would TDC and speed sensors be the same on late cars as they are on the early ones?????

The 86 fuel rail may have to be used if/when a turbo is installed as it's best to have a better adjustable fuel pressure regulator. The 83 fuel rail doesn't lend itself to this. But since the turbo will be added later use the 83 fuel rail for now.

Yes the idle bypass valve for the 83 has to be used as the older DME's don't have the circuitry to drive the newer ones. Good call! By the way the current for the old style comes from the fuel pump circuit.

Speed and reference sensors are the same in the same location. There is a third sensor on the 86's bracket for dealer testing. It drives some crazy thinking it's supposed to be plug into something!

Sounds tough to me but I'm sure you guys can talk me through it when the time comes. Is there anything else from the 86 car besides the engine that I will need. What if I use the 86 ecu? Would that simplify things or make them harder or neither? How long should it take to do the switch with 2 people?

FWIW guys IIRC SoCal installed a 86 engine in his 83 last year, I got the sunroof motor and Todd ended up with the carpet and some tranny parts out of the doner car.

Good luck!

ok......whats FWIW anIIRC i've been wondering for a while.lol

For What It is Worth = FWIW
If I Remmeber Correctly = IIRC

Ther is a three page document somewhere on the net with all the silly acronyms listed.

HTH

I would do a minimum swap just to get it up and running.

One NA engine replacing another NA engine. No fancy stuff. No turbo.

You will also need the top radiator hose from the 86. The cooling system bleed is in the aluminum elbow on the top of the block. Don't loose the bleed screw. It doesn't have to come all the way out to bleed the system. It's worth the price of a radiator hose if you didn't get on with the engine. It's a better bleeder that the red plastic plug in the rubber hose.

Once you get the engine up and running then think about swaping the DME out. You will also need the DME wire harness, the AFS and the vacuum tubing for the later idle control valve.

Hang on to the 83 block as it has the forged rods in it you will need for a turbo. The 86 doesn't.

If you can put some time into the change over about 20 hours. It's not the two workers that takes time it's making darn sure you have things set up right before tightening bolts or cranking the engine over.

Scott. Have the retracting section for the rear cargo cover if you are interested. Should take 30 minutes to R&R yours.

So do you think since I'm putting the supercharger on it I should take the pistons and rods from the 83 and put them in the 86 with some new rings. Also should I do the rod/main bearings? I don't want to have to re-time the engine since it has new belts on it already.

The Sachs cluth has the spring clutch center right?

You'll find out if the clutch has springs when you take it out.

Just get the engines swapped and running first!

ITC = I'm totally confused
IRFC = I'm really F'ing confused
TSF = Todwic, stop farting
IWJLAI = I was just looking at it!
N= nopers
Y = yip
D = dunno
IS = I'm stupid
IWS = I'm with stupid
ICSC = I crashed stupids car
SCIMC = Stupid crashed into my car
YAPH = you're a poop head


Frank B

IAPS = It's A Porsche Stupid!