In general, the US Spec '85 and '86 motors ( S3 32v ) are the same. However, while swapping my '86 motor for an '85 motor, I did come across some differences. I figured it might be worth documenting here.

First thing was pointed out in another thread, so I am repeating here:

PET shows different part numbers for the S3 wiring harnesses:
85: 928 607 002 01
86: 928 607 002 10



The consensus there was that it _may_ mean a Japanese spec harness and it made no difference in any case. This is the one difference I did not see personally, as I reused the same harness.

 

Second change I noted was that the bracket that holds the diagnostic port and the holds the TPS connectors were different.

The '85 version made the Diagnostic port unusable, but did make the TPS connector a little more accessible:



The '86 bracket makes the diagnostic port accessible, but pushed the TPS connector to the rear:

 

Next thing is that the bracket in the rear of the motor for the fuel return host and the CPS sensor was different. The black one is from the '85 ( I powdercoated it) and the bare metal is the '86 version.

 

Most annoying thing I have come across so far: The drivers side Cam belt covers are different.
If you look at the '86 version, the upper cover has a mounting bolt in ithe inner corner and the outside "leg" only comes down 2 or 3 cm:



However, my '85 version, the outside leg comes all the way down to BELOW the PS pump bracket and has a mounting bold dead center, but not one in the corner inside of the leg:



This is actually a really big deal if you want to take that cover off, for instance to check your cam timing with Porkens PK32V'r

You can't get the cover off with the PS pump in place. Well, you can, but it requires above average force and extreme language, and you will leave some of your nice powder coating on the PS Pump bracket ( you can see where mine scraped and left paint on the bracket). And, as Porken predicted here the cam timing was way off.

 

I've noticed the timing belt cover difference too when I pulled the parts car apart.

By the way, the valve cover bolts are different too but that's an internal difference.

 

Center TB cover is and dipstick tube are different as well.

 

I had forgotten the center cover and had forgotten about the dipstick tube ( and crappo wire coat hanger dipstick) Good call!

Center cover makes sense of course, since upper cover is different.

 

More on the Dipstick, from this thread:

The '85 dip stick is the ugly bent coat hanger style. You can't even easily upgrade it with the '86 dipstick because they are different lengths:



Different tube lengths:

 

And the Center cover differences:

The Dipstick tube mounting scheme is entirely different:
'85 Cover:



Versus the '86 cover. Note the extra bulge and mounting point for dip stick tube?

 

There's also differences between very early '85, early '85, and late '85, vs. '86.

Yours is an early '85, with the 16V type dipstick and cam covers, and rearward test plug placement.

Early '85 cam gears don't have the 10mm alignment holes and no front timing mark.



The large front cam gear timing notch is paired with the revised cam gear covers, with the breather tower moved forward (so you can check the timing down the hole).

Here is my old mid/late '85 (#1972), with factory mix and match covers (note position and height of L vs R breather tubes), forward mounted test port, and late dipstick.



Early '85 have an odd FPR return hose. For some reason the single FPR was originally planned to be on the left (as shown in the WSM) but was moved to the right, necessitating a long hose plus a small bracket at the rear throttle body housing bolt for a blue plastic clip.




Don't forget '85 paper vs. (very expensive) '86 metal intake manifold gaskets! ('86 can use the paper ones, too.)

 

The timing cover are different because the tensioner idler arm is cranked forward on 86my.

 

KenRudd what's the VIN on that '85?
I have one that is "0888" out of "2219" and it doesn't have the things you posted, my other two are #'s "2159" of "2219" (I know, scratching my head too) and "1744" of "2219".
All mine look like PorKen's.

The numbers are from the 928 Registry.

Dave

 

I have 0865 and my engine has everything that Ken's does with the exception of the diagnostic port configuration, which I assume was updated at some point.

 

Wow that's close, they may have been on the assembly line floor at the same time

 

That early style fuel return line looks nice, actually. On the later ones it's tricky to cut a new line to the right length. Too short- kinks. Too long... also kinks.