MYSTERY 901 gearbox

POR71 · 07-15-2010, 12:08 PM

Hi,
I've been offered a 901 gearbox with small LWB spindles on a normal 911/912 shifting mecanism. The 901/XX or 902/XX number isn't readable anymore.
The only thing he can provide me is with the serial number.
7399102

The owner claims it's a 901/06, so 4-speed indicating that number.....

What could it be 4 or 5 speed regarding the serial number 7399102?
ATB, Ivan

Grady Clay · 07-15-2010, 01:21 PM

Ivan,

7399102
You have a “find”.

This is a 1969, mag case, ‘Ratios-to-order’ transmission.
The transmission number range is 7399101 to 7399111.
You have the second example of ten made.
These transmissions did not have a type number.

Please post images so we can decide what axle flanges it has.
Normal would be 108 mm diameter, four M10 bolts and two 10 mm roll pins.

If this does not have a ZF LSD, then it has the ‘simplified’ differential and needs an update.

Best,
Grady

POR71 · 07-15-2010, 02:03 PM

Hi,
"Ratios-to-order", mmm and is it 4 or 5 speed? or not defined,
He claims it was attached to a 901/03 engine 61912XX, and that's a 2,0 L engine from 1969...T engine so not a lot of power there, where they only suplied to the S types?

The axle flanges are the ones you state....
Are these valuable to racers i suspect? I was just looking for a 5 speeder....:-)

Unfortunately no picture yet
ATB, Ivan

Matt Monson · 07-15-2010, 03:06 PM

Ivan,
It's only as valuable as the ratios inside. You need to find out what's in it...

djpateman · 07-15-2010, 06:33 PM

Very interesting. No telling what is in there until it is disassembled. If you are looking for a ready to use box, then it may not be your best bet. If the price is cheap enough, then it could be worth the risk. If you decide to pass, let us know.

Grady Clay · 07-16-2010, 05:39 AM

Ivan,

Yes, it could be a 4-speed or a 5-speed but I would bet it is 5-speed.

Does it have a LSD?

I recommend you carefully inspect the 901/03 engine, It may be it is a rallye engine as Porsche built some that were supposedly a 911T but the performance of 911S and more.

Can you find the VIN of the 911 the engine and trans are from?
Any other information?

Best,
Grady

daepp · 07-16-2010, 08:42 AM

This looks promising!

kenikh · 07-16-2010, 09:18 AM

I'd buy it on speculation value alone. Cracking it open is easy and the gear letters are typically stamped on the gears. Heck, there may even be a 904 mainshaft in there! If you pass, I'd love to buy it!

POR71 · 07-16-2010, 01:35 PM

Hi,
Just bought the lot.
Apparentely he bought the car for parts.
There is another engine with number 619186X lying around, some missing parts , I'll be checking that one too whilst I'm there. Probably sunday late for the pick up....so have some patience for pics till next week.....

How do I spot difference between LSD and simpel diff.?
I'll see if he's still got the shell or VIN number whilst I' m collecting....

Any other information? Yezzz the 901/03 engine is missing exhausts/alternator/cooling fan/carbs/cooling plate and intake. He's still got the spares but wants the use them in other projects....we'll see maybe I can twist he's arm to loosen the parts....

And it's a long drive but price is OK and it's apparentely a suprise what's inside, Whom can resist to that....

Keep you posted!

ATB,
Ivan

tcar · 07-16-2010, 01:51 PM

Quote:

Originally Posted by POR71

How do I spot difference between LSD and simpel diff.?

Turn one axle, if the other axle turns the opposite direction, it has LSD.

If the same or intermittently the same, Not.

There may be some tag or something to id it, too.

djpateman · 07-16-2010, 03:25 PM

If you are looking at any 2.0 engines, please see if you can get the info detailed in this thread:
Third number on engine case - Pelican Parts Technical BBS
essentially: serial #, type #, build #, and if you can see the top of the case, get the case pairing #'s please.

On special trannys there is often a metal tag with the gear letters stamped on it.

Zeke · 07-16-2010, 04:07 PM

How do you tell if it has a limited slip? Turn the hubs. If they don't spin the same way, it's not. If it's in gear, one won't turn the other very well at all.

POR71 · 07-19-2010, 10:09 AM

Hi,
The car appear to be a 1972 Targa. Was heavily damaged (time ago) at the front.
And has a dent on the mount on the rear shocks. Guess the parts didn't originate from this car...No porsche paperwork with the car. Car originates from Germany,only TUV papers from the body kit.

Rest to follow..

POR71 · 07-19-2010, 10:13 AM

Hi,
As for the gearbox. If I turn a spindle on one side the other turns in the opposite direction.
No identification plate for the gears.
How do I go further from here, take it apart or inspect it through a hole to see what's inside? Is there an easy way to tell it's a 4 or 5 speeder?

POR71 · 07-19-2010, 10:14 AM

Just got the chassis number: 9112510880

POR71 · 07-19-2010, 10:20 AM

Hi,
As for the 901/03 engine (according to the owner was bolted to the gearbox)
It appears to have cast iron liners and intake port is 32 mm. so nothing special here I guess.

POR71 · 07-19-2010, 10:23 AM

Hi,
As for the other 901/03 engine:
It has aluminium cylinders, intake ports are 32 mm and the cylinder heads got an opening (whch is plugged) for an injector, the other 901/03 hasn't got these features....

Matt Monson · 07-19-2010, 10:45 AM

Ivan,
According to the Porsche spec book, all of the boxes in the range that Grady listed above would be 5 speed. If you pulled the tailcover off of it, it would be really easy to tell. Either there would be reverse and first there under the cover or just reverse. If there's a first, then it's a 5spd. This would also help determine the ratios because almost all the special ratio boxes had either an AA, B, or C first gear instead of the standard A.

But even an A in first is no guarantee of what follows. To really know all the ratios you've got to pull out the whole stack, which isn't terribly hard, but may be something the seller isn't too keen on happening prior to the exchange of $$$.

djpateman · 07-19-2010, 05:43 PM

Ivan, a couple of things. Is there any type # stamped into the transmission case at all? What about a casting date; generally on the opposite side from the diff cover along with the casting part # for the case. If you need a step by step procedure to check out your gearbox I'm sure we can help.

On the engines there are build #'s like the one pictured (23500 or is it 23508) if you wouldn't mind, the build #'s, serial #'s and the case pairing #'s (on the bosses on top of the case at the parting line) would be very useful for my research.

POR71 · 07-21-2010, 12:14 PM

Hi,
No type number stamped into the gearbox.
For the year code will check this tomorow.

As for the engines:
The one with cast iron liners
*6191283*
901/03
21362
901.101.101 2R

The one with the aluminium liners
*6191866*
901/03
23508
901.101.101 2R

Will check for the case pairing numbers tomorrow, thought you meant the 901.101.101 2R numbers...
The difference between the engine numbers is 583 engines, and the difference between the smaller numbers is 2146, is this normal?
The second engine 6191866 has much sharper numbers in it, especially the 1...
ATB, Ivan