looking for good info on 3.2 swap into an early car

cnielsen · 01-13-2004, 03:39 AM

I have tried searching the archive but I did not come up with the kind of info I was looking for. Does anyone have any good info on installing a 3.2 into a '69-73 chassis. Mainly, I am looking for wiring help. What does it take to hook up the brain to the rest of the car? Any other pitfalls to look out for???

Thanks, Chris

IROC · IROC's Garage

Having swapped a 3.2 into my '76, I'll throw in my two pfennig. Interfacing the "brain" with the rest of the car isn't that difficult, really. All you really need to do is get a couple of 12V power sources (from your fuseblock) to the DME/DME relay. The DME really only connects to existing components on the engine itself and not so much into the rest of the car (aside from the above mentioned power needs and a connection to a tach).

What you will have to sort out is supplying fuel to the engine (not a huge deal, really) and sorting out the wiring from the engine that controls the starter and all of the signals from the various sending units. Porsche seemed to be relatively consistent on wiring of gauges, etc., over the years, so this is also not a *huge* task.

My advice would be to gain a good understanding of what connections exist on the 3.2 (gauges, power, tach, starter, etc) and then figure out the best way to interface them with your particular car. In the end, it's probably not going to be as bad as you think.

Mike

cnielsen · 01-13-2004, 05:13 AM

What is difficult about the fuel supply? I will probably need a carrera fuel pump but what are the other problems? Is it a circulating system or just a supply line? Do I need any of that "stuff" that is found on the left engine bay of a carrera? Accumulator???

Chris

IROC · IROC's Garage

Nothing difficult - just things to sort out. The fuel supply from the pump needs to interface with the fuel filter in the engine bay and to make that happen on my car, I had to fiddle around with some fittings to get it to work.

Plus, you'll need to adapt the fuel return line from the engine to the tank. On my car, I simply cut off the threaded fitting that comes out of the fuel pressure regulator on the 3.2 and replaced it with a barbed hose fitting and then ran a new fuel line down to the threaded return line on my car.

Nothing major - just things to tend to...

Mike

mjshira · 01-13-2004, 08:48 AM

send me a PM and I'll give you my number

kiesan · 01-13-2004, 08:48 AM

Hey Chris I noticed you're in Seattle as I am. I have some 3.2 Carrerra stuff (Fuel rail, DME wiring harness) left over after I converted my car to PMO carbs and Electromotive. If you need it let me know and I can sell it at a fair price.

cnielsen · 01-13-2004, 08:56 AM

Thanks Kie and everyone else! I will try to sort things out. I have not tried the transplant yet but want to eliminate any surprises when I do!

Kie, sounds like we have some similar interests...Ducatis and Porshes. I'll definately contact you if I need any of those 3.2 parts!

Chris
cnielsen@u.washington.edu

chuckw951 · 11:04 AM

Quote:

Originally posted by cnielsen
I have tried searching the archive but I did not come up with the kind of info I was looking for. Does anyone have any good info on installing a 3.2 into a '69-73 chassis. Mainly, I am looking for wiring help. What does it take to hook up the brain to the rest of the car? Any other pitfalls to look out for???

Thanks, Chris

Chris,

I believe the wiring for the 69, 70/71 and 72, 73 is different and would also vary depending on where the car in question is a 911T or 911E/S. For 1969 there is no 14 pin connector for the wiring harness for the engine/gauges, but rather a set of 3 or 4 6pin plugs behind the motor. Seems to me that the 3.2 conversion would be easier with a 70+ car because you already have the 14 pin connector in the engine compartment. I've seen a "pin out" diagram for 3.2 motors posted on the internet. Wiring diagrams are available from pelican parts pages.

Another thing to consider is that the early cars had an alternator with an externator regulator where as the later cars had a an alternator with an integrated regulator so that should make the wiring a bit easier.

You'll also need to consider your transmission choice. The 69 901 will not bolt up to the 3.2 without a special flywheel, but the 70/71 901 and 72/73 915 will. The 915 would be the preferred transmission for the 3.2 because it can handle the torque. (edit: note that some mods might be needed to the transmission for the sensor pickup which I'm not familiar with)

You may need to install early sensors on the 3.2 motor so that the stock gauges (oil temp, pressure) work or I suppose you could update to later gauges. I don't think the stock early tach will work with the 3.2 motor.

Adapting the fuel lines shouldn't be too hard, but again that will vary depending on the year of the early car and whether or not it orginally had carbs or fuel injection and if the 3.2 motor needs a return line. I'm not sure where the fuel pump is for the 3.2 cars. But please check the quality of the fuel hoses. The early cars had lower pressure fuel systems than the SCs and Carreras.

Which exhaust are you using and will it have an O2 sensor? I believe the fuel ignition needs that sensor.

Finally you may consider back dating your heating system by using the early engine tin on the 3.2 motor.

I know I haven't provided the really specific info you're looking for but hope I've outlined some things to think about as the project moves forward. I don't think anyone has written a comprehensive 911 hotrodding book yet.

Rick Lee · Rick Lee's Garage

I participated in this 3.2 swap. JW helped out by phone too.

http://www.pelicanparts.com/MotorCity/marcesq1/

chuckw951 · 01-13-2004, 11:01 AM

Quote:

Originally posted by Richard LeSchander
I participated in this 3.2 swap. JW helped out by phone too.

http://www.pelicanparts.com/MotorCity/marcesq1/

There are so many "small" issues with these swaps. I didn't even think about notching the bellhousing or that the male 14 pin connector would have to be moved forward. Great project.

In my last post I don't raise issues with the oil cooling system. For my swap I used an early engine cooler on the 3.0 motor so that the S oil line from the cooler to the early oil tank could be used. I did need a special line (flexible hose rather than hardline) from the oil scavenge pump above the trans to the oil tank.
So I think if you are installing a 3.2 into an early car you need to think about the cooling system. Did your car come with a front oil cooler?

cnielsen · 01-13-2004, 03:32 PM

Wow, thanks for this link!!!

http://www.pelicanparts.com/MotorCity/marcesq1/

This goes into the wiring details and fuel/oil line details that I was looking for. Even though this was not for an early car, I think most of the info can be applied or at least help for a better understanding.

Thanks!

Chris

ZCAT3 · 12-02-2004, 01:40 PM

I am looking at doing a 3.2 into a 69 911S. I would like to try this using the stock 901 trans if possible. With that in mind, what is the special flywheel that is needed to mate the 69 901 to the Carrera 3.2?

Jim Garfield · 12-02-2004, 03:29 PM

Bill, did you just get that 3.2 yesterday? Seemed like a good deal if it's the one I'm thinking of. I was thinking of bidding but the local pickup was a problem.

I think that PowerHaus? in Arizona might do that flywheel.

If you don't mind me asking, what is the header/muffler setup on that engine? Sportmuffler?

pu911 · 12-02-2004, 03:35 PM

Patrick motorsports sells flywheels for that application. Just don't do any drag race starts in first gear.
Phil

Jim Garfield · 12-02-2004, 03:43 PM

Oops, Patrick is who I was thinking of.

randywebb · 12-02-2004, 03:44 PM

Right, as does Kennedy.

__________
You will need to put the old oil press. sender in the spot near the breather cap (there is an oil temp. idiot light sender there now).

I also found that my oil temp. gauge does not work. I haven't figured out why yet. If anybody knows whether the 3.2L sender is or is not compatible with the '73 gauge, pls post.

You will need to move a few wires in the 14 pin engine compartment connector.

If you keep the DME, you are out of my league.

randywebb · 12-02-2004, 03:49 PM

Oh - one other thing - I posted a few months ago about how to make an adapter for the trans. so you can use the 915 style trans crossbar with the nice replaceable rubber -- or Wevo -- mounts.

Search it up.

randywebb · 12-02-2004, 04:10 PM

couple of corrections to a post near the top:

- the stock 1973.5 tach will work with the 3.2 motor just fine, at least using a MSD box - just run the tach wire into the end of the box

- the 911 type trans uses a 225mm clutch; it still needs a special adapter flywheel, I think.

ZCAT3 · 12-02-2004, 05:11 PM

Jim - yes I went ahead and bought that 3.2. I have yet to see it, but it supposedly has all the parts for transplant into an early car (other than the fuel pump and lines, and the ECU and harness are there any other parts I should look for?). It does sound like I will either need to get the special flywheel or a 915. As I have seen several 915s go for less than $1000 and the 3.2 includes the pressure plate and clutch kit for a 915 it may be cheaper (and certainly more durable) to go this way.

Akkurat, the shop that has the engine, was unsure what the headers were. They said they look like production fabricated headers, as opposed to one off custom jobs, but they did not see any manufacturer marks. They have no heat and are said to be of excellent quality. To be getting 224 RWHP out of a basically stock 3.2 those headers must be doing something right. TThe muffler looks like a standard sport muffler from the pictures. The prior owner wants to get more hardcore at the track and is going to a 3.6 or 3.8.

I am going to look at the engine and parts tomorrow and can take some pictures. It will likely be a few days before I bring it home.

Any advice on the 3.2 swap is appreciated. I presume the external cooler on my 69S should be sufficient for the 3.2 as it is about the same as what was on the Carreras.