NF vs. NG motors

[Stott Hare]

Close, but this still requires correction.  The 100 didn't use the NF motor.
It also used the NG motor, except the head doesn't have a vacuum pump.  Only
the later model 5000 non-turbos had the NF motor (which didn't have the
vacuum pump either).

Don't worry, we get this straight eventually.
HTH,
-S

Stott Hare
85 Callaway 4ktq(NG Callaway conversion in planning)
89 100q(NG)
89 200q (MC2)

-----Original Message-----
From: quattro-admin at audifans.com [mailto:quattro-admin at audifans.com]On
Behalf Of Huw Powell
Sent: Monday, April 09, 2001 4:31 PM
To: Michael Gough; quattro at audifans.com
Subject: Re: NF vs. NG motors


I'll list the differences one more time.  Please listen louder...

the NF and NG are identical from the oil pan gasket to the head gasket.

Generally, the NF is used in the "big" cars (5000/100) and the NG in the
"little" ones (cgt/80/90).

the big car oil pan is a bit different - there is a "dent" in the little
car oil pan to allow room for the radiator and AC condenser.  All i5 oil
pans are interchangeable except for this little difference.  IE you can
use your old one.

from the head gasket up there are radical differences.  The NF looks
like your 4kq/cgt engine, except for the lack of a vacuum pump.  The
intake manifold is a bit different but bolts up exactly the same.  This
is the engine you want to use.  You use your fuel/exhaust system, and it
is plug and play.

The NG uses a two piece intake manifold, and the injectors are mounted
in the manifold.  If you want to use this engine you will also need the
fuel injector lines as they are routed differently, and the black boot
from airbox to throttle body, and all the clutter on top of the intake
manifold (cruise, throttle stuff, etc) since it is different.  Your
throttle cable may not be a simple hook up either.  These heads also
have the vacuum pump.

you will use your engine mounts.  You will also use your old distributor
and cam cover, in order to use your engine management system intact.

There are many pictures of an NF being rebuilt and installed in a 4kq on
my website starting with this file:

http://www.humanspeakers.com/audi/rebuild.htm

I do not have many pictures of the NG set up, but there is a poor photo
of an 87.5 cgt bay here:

http://www.humanspeakers.com/cgi-bin/humanspeakers/audi_img.pl?image=engineN
G.jpg&desc=NG%20engine%20in%2087.5%20CGT

> I was wondering if anyone can tell me all the differences between the NF
and NG code engines. Is the only thing different the intake manifold and
where the injectors go? Speaking of injectors, will my 4k cis-e injectors
plug in to the head/ manifold? Lastly, do both engines have the same cam,
and the 40mm valves?

no, see above.  yes.  yes.

> Which is better to swap into a 4k? I am going to use my fuel and ignition
system and my intake/exhaust manifolds.

the NF

> Do these engines have more low end torque than my 2.2 JT? Lastly, should I
use the whole long block, or just the short block with my head and my 38mm
valves?

yes they do.  more over the entire rpm range.  use the whole long block.

[ > Beats me what the difference is. One is for the 87.5 Coupe GT, the
other is a 5ks engine. Since the 5ks went into my CGT trouble free,
whatever the differences are must be minor and insignificant.

spurious logic that means nothing]

--
Huw Powell

http://www.humanspeakers.com/audi/

http://www.humanthoughts.org/