Re: Engine swaps

[George Graves <gmgraves@xxxxxxxxxxx>]

OK, I've not actually done this myself as I was lucky enough to find a 
very low milage Milano Verde engine, but I've seen the process done on 
someone else's car.

First of all, there is a fair documentation of the process available at

http://www.apedirect.com/larryjrprojects.html

But keep in mind that this is a 24-valve motor. The process for the 
12-valve motor is very similar, the main difference is the heads and 
exhaust headers on the 24-valve motor.

There are essentially, two parts to this process:
1) Changing the engine block over from a tranversely mounted FWD 
engine/transaxel to a longitudinally mounted RWD engine.
2) Modifying the fuel-injection system for longitudinal operation.

First thing is that the engine block WILL fit your current 2.5 liter (I 
presume you currently have a 2.5 liter V-6 in your car) oil pan with 
some modification. Some new holes must be drilled in the block and 
tapped and the rear motor mount from your old engine must be bolted up 
to the 164 block as the FWD engine doesn't have this piece. Also, if 
you get a late-model engine, you will find that the flywheel bolts from 
your 2.5 engine (you need to use the RWD flywheel not the 164 starter 
ring wheel) won't fit the 164's crank because they are a different 
thread pitch. Good luck locating the correct ones. If you get an early 
164 engine, you won't have this problem.

Next, the distributor must be moved. The FWD engine drives the ignition 
distributor from what will be the rear of the driver's side camshaft. 
This has to be moved back to the passenger side of the engine in the 
front, in unit with the oil pump. You can use the distributor that came 
with the donor engine, but you will need the drive gear from your old 
distributor. Frankly, it looks as if  you will be better-off to use the 
distributor from your 2.5 liter engine here. If your 164 engine is a 
late enough model to incorporate Bosch Motronic Fuel Injection, rather 
than the L-Jetronic used in the GTV-6/Milano, you should remove all of 
the "points" related stuff, as Motronic uses a timing disc on the front 
of the crankshaft for all of that and the distributor in a Motronic 
equipped system just distributes the spark and does not power the 
ignition coil.

You also need to purchase a cover plate to plug the hole in the back of 
the head where the distributor USED to fit or you won't be able to keep 
oil in the engine (!)

Luckily, your 2.5 liter exhaust headers will fit the 12-valve 3-liter 
heads, so your old exhaust manifolds will work fine on your new engine. 
If you decide to go with a 24-valve 164 motor, be advised that the 
heads are quite different, and new headers will have to be fabricated 
because the manifolds from the FWD donor car won't work because they 
are cast at an angle to facilitate front wheel drive with an engine 
mounted cross-wise in the engine bay.

Once the engine is installed You have to deal with the intake. I 
strongly suggest that you take the inlet air plenum from your current 
motor along with the throttle body, cold start mechanism, intake air 
hose and throttle actuating mechanism from your current car. Don't make 
yourself crazy by trying to adapt the FWD intake setup to your RWD 
Alfa. But if you have a Motronic engine, you'll have to deal with the 
Motronic system as a whole, and that includes the intake plenum and 
long runners unless, of course, you decide to convert it back to 
L-Jetronic. If you do keep the Motronic setup, this will involve 
getting a 'U' shaped connector fabricated from aluminum as the intake 
from the airflow meter will end-up in your glove compartment, on the 
cabin side of the firewall otherwise.

If you do keep the air intake plenum and throttle-body assembly from 
your 2.5 liter motor, be sure to order a new 3-liter airflow meter 
(AFM). This can either be ordered as a new part, or you can fit a used 
one from someplace like APE. Also, if you feel adventuresome, it has 
been said that some benefit can be gained by fitting an AFM from a 
similar vintage L-Jetronic equipped BMW 6-cylinder engine (63X and 73X 
models, available at junkyards). It has a larger diameter and the hose 
from the AFM to the throttle body must be soaked in boiling water to 
stretch it to fit the BMW AFM mouth. I'd give the article referenced 
below a careful read before trying it though.

http://www.gtv6.org/index.shtml

Click on "Larger AFM Installation"

Name on article is:

"Larger (BMW) Bosch Air Flow Meter Installation"

My own experience says that you DO need the three liter AFM if you're 
going to fit a 3-liter engine. The 2.5 liter AFM from your current 
engine might look the same and certainly will work, but it's not 
optimum and you might experience insufficient air at high RPMs making 
the engine run rich and reducing power where it should be at it's 
highest.

These are just some of things that I know about what has to be done to 
affect this modification. APE in Tracy CA used to offer 12-valve 164 
engines already converted to RWD for use in GTV-6s and Milanos for 
about $2000 with your old engine in exchange. You still had to use your 
2.5's oil pan and rear motor mount strut, if I remember correctly, but 
at least all the difficult stuff was done for you (like the drilling 
and tapping and the distributor conversion). I don't know if they still 
offer this service, but a quick call to them at 1- (209) 833-8330 
should yield you your answer.

BTW, if you are going to do this on a GTV-6, I cannot too strongly 
recommend that you also get a Power Steering conversion kit from APE 
and install PS in your GTV-6 while the engine's out . You'll thank 
yourself every time you get in the car from now on, believe me.

George Graves
'86 GTV-6 3.0S


On Wednesday, May 28, 2003, at 09:47 AM, alfa-digest wrote:


> Date: Wed, 28 May 2003 08:23:48 -0400
> From: Brooks Coburn <bacoburn@domain.elided>
> Subject: Engine swaps
>
> While the digesters are on the subject of engine swaps, what potential
> is there to swap a 3.0L v-6 from a 164 into the Milano/GTV6 models?
> I've read some notes others have written but they were incomplete
> regarding what needs to be physically done.  Was hoping to see more of
> the nuts and bolts of what parts and changes need to be accomplished.
> EFI mod was discussed a bit in Nizam's site but he started with a Verde
> not a 2.5L Milano.  Major mod for his installation was the Motoronic
> system.  That is grounds enough to gut a unfixable 164 but how much
> different is the 164's engine from the older v-6s?
>
> Anyone do one of these swaps without beating themselves to death in the
> process?  Fair number of 164s out there but no (or very pricey) Verde
> engines.
>
> Thanks,
> Brooks
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