pdxfj

Hello everyone,

I have pulled the engine out of my 86 NA to address the usual 30 year oil leaks. I suspect the rod bearings need to be done as well since there is a nice amount of gold flake in the oil when I change it. Of course it could also be the main bearings or even the balance shaft(s).

The head is off and the bores are in good shape, no scoring or anything. Car ran great before pulling the engine and passed our local emissions testing with flying colors just a few months ago.

My car says it has 116k on it, but I suspect it's much higher than that and/or it had a rather abused life before me.

There is a chance I can get my hands on a recently rebuilt 84 engine that has been gone through from front to back. All new seals, bearings, valve job, etc.

It is very tempting since it would be just a drop in and go. I trust the person who rebuilt it, and it is currently in a running and driving car.

I realize the AFM is likely different and maybe even the idle control valve. I’m guessing the differences are mostly with sensors and such, but mechanically there are likely no differences.

Anyone point out anything that would be a major pain to deal with or ?

Thanks!

V2Rocket

the engine itself as a lump is plug and play. re-use all the sensors, brackets and plumbing and stuff from the 86 car.

the only change you may need to account for is the coolant temp sensor at the front of the block, driver side...at some point in 1984 they swapped it from the small "early" type to the larger "late" type but the function is more or less identical.

pdxfj

Are you referring to the DME temp sensor or the temp gauge sensor?

Thanks for the info. If the cost of parts and such to repair my engine is within reach of the rebuilt one, it seem the logical path would be to get it.

V2Rocket

the gauge one.


on early-early (82-84?) cars it had a one-terminal sensor and one wire to the gauge.
on late-early (84?-85) cars it used the late-late-type 2-terminal sensor but still only one wire hooked up to the gauge.

on late-late (85.5+) cars the two-terminal sensor has 2 wires running to the gauge.

all youd have to do is drill/tap the early-early block to fit the late-late sensor.

Kurt R

The 86 is going to have a better camshaft.

V2Rocket

barely...not worth swapping unless you've already got a reason to remove the 84 cam.

pdxfj

Hmm... Interesting about the cam.. Can you provide a bit more information?

Could swap the towers if I felt like it.. ??

V2Rocket

yes the cam towers are interchangeable.
the 82-85 NA and 86-89 944T camshaft is called the -05R
the 85.5-88 NA camshaft is the -09R

the cams are the same in all aspects, except the -09R has 8 degrees more exhaust duration and 1mm more exhaust lift than the -05R.

cam was pretty much the only significant change in parts from "early" to "late" engines...and contributed to the 85.5-87 engine making 147hp in US tune vs the 82-85 making 143.

pdxfj

Thanks for the insights. I figured both would be the same mechanically, just wondering about sensor differences between the years.

Will have to wait and see what pans out.

Legoland951

V2 is pretty much right on. The connecting rods are also different in that the early ones are forged and the late ones are cast if memory serves. Also, the piston skirts are of a different configuration but it will function in both cars.

Other than the block itself, the fuel injection rail, lines, and location are different. AFM is definitely different but you can use your original one to your car. The alternator is also different. These are things from the top of my head after almost a decade of 944 inactivity.

StoogeMoe

Hey long time no hear Legoland.

Your memory has gotten foggy over 10 years. Only the 83 came with forged connecting rods. (And turbos)

The only other difference I can think of is the balance shafts are different.

V2Rocket

^^back from the dead...

konakat

The forged rods did extend into early '84, so there is a chance depending on build date.