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Discussion Starter #1
Hi folks,

I'm looking for a new transmission for my car and found one for sale. It's a five speed, so of course later, but I believe my car originally came with a split-case. The numbers cast in the case are 1010-13100 and AL C3, and the numbers hand stamped in the case tangs are 99400 and 5M9/41. Can anyone verify that this transmission and bell housing will work with my engine? I've requested photos from the seller and hope to have them soon.

Many thanks,

Tony
 

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Hi Tony

What's the chassis number of your Spider & do you have the production date from the Archives ?? That'll tell us what transmission it had originally

1010-13100 is a casting part number
AL C3 - No idea
99400 - no idea
5M9/41 - 5 speed Manual and the speedo drive is paired to a 9/41 rear axle ratio (4.555 to 1)

Ciao
Greig
 

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Richard Jemison
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Trans

I`m pretty certain your 58 came with a tunnle case. In any event the mounts for either 4 speed trans will be different than for a 5 speed. As well the spacer between the engine and split case trans are very different.
Opening in the tunnel is in a different place than for a 5 speed.

#s other than the 9/41 mean nothing. he 9/41 indicates speedometer gears for a 4.56 rear diff ratio.
 

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The split case was introduced in September '58 and the tunnel box ceased to be used.

Richard is right, the sheet metal of the floor is different between the tunnel case and the split case. The transmission supports and the prop shafts are very different for the 2 different boxes.

Ciao
Greig
 

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There is a recent thread on this subject. I don't recall the title but there is a lot of info available there if you can find it. In essence, the conclusion is that putting a later 5 speed into your car will entail drastic spacing down of the cross member with uncertain impact on the universal joints. There are cross members available that have a deeper recess that may avoid the spacers but the question about the u-joints remain. The alternative is modification to the floor pan.
 

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I'm sure it's been written elsewhere on this forum, but to help the discussion along, I will add that Spider and Spider Veloce from 1495.04811 had the split case transmission, according to the shop manual supplement. My car is 1495.05875, which was ex works as of January 1959, per Centro Storico. I have a split case 4-speed in mine, and I am practically certain that this was original.

Tony, from memory, your car was a split case, too. I do not know whether a 5-spped slips into place, but I suspect that a different rear mounting cross bracket will be needed or that you have to change the tail housing to get the smaller mount for the 750. I do not know whether the bell housing will mate up either, but you're welcome to bring it by to mate with my spare 750 block for a trial fit.
 

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I am installing a 101 1600 5 speed transmission in a late 1959 Spider Veloce that had a split case 4 speed transmission. I know that if you car had a split case transmission instead of the tunnel case transmission it should not be problem using a 101 1300 SS/SZ or 101 1600 transmission. The 105 1600 transmission has a larger diameter rear transmission mount and may not fit in the 101 1300 transmission mount.
 

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Discussion Starter #8
Thanks for all the excellent advice. My serial nos.:
Body: AR1495.F.05176
Engine: AR 1315 31976
Body: 24158

Mr Fazio says it was built 17 November, 1958, so Grieg and Tom are correct that it was originally supplied with a split case. The transmission that came with the car (not sure if original) is indeed a split-case, number stamped on flange: 40780. Cast into both the exterior under the shift rod, and inside the bell housing is 10112-13102. I poured a quantity of water out of it along with transmission fluid, and while the water was not orange, I suspect it will need extensive work!

I know the veloce transmission mounts require a set of 6 steel bushings (and longer bolts) because of the different engine mounts and position- this is getting complicated! I'll search for that previous string, and thanks again to all.

Tony
 

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Hi Tony

Fortunate man, it's a split case car, so the sheet metal on the transmission tunnel is the right shape & height for the taller split case box

Your split case should have the external screw adjuster on the turret for the push-down-lock-out reverse function and would have had the early syncro's and synchro hubs to take Dentax oil. 10112 is the part number for the later 1600cc 101 Series Giulia's so your car has received a 5 speed upgrade - it's a good thing, keeps the revs acceptable at freeway speeds.

Water in the oil will necessitate a comprehensive rebuild.........unless you have someone who is *very good* at boxes, I'd suggest you contacted Richard Jemison - see Post #3 above. RJ is good...actually better than good and he really knows his stuff, especially the gearboxes. Shipping to & from Florida plus the rebuild will be expensive, but doing it on the cheap & then pulling it out several times afterwards becomes just as expensive & is a real PITA........plus risky to the paint work. Do it once and do it right.

"Veloce transmission mounts require a set of 6 steel bushings" - No they are actually aluminium 'bushes' or more correctly lengths of aluminium round bar. What works for one car may not work for yours, these things are easy enough to turn on a lathe & your critical task is to get the measurements right so that output shaft the & short drive shaft are in line. Takes a bit of fiddling.

SWB with the split case & an added 5th gear - a really sweet combination for a Spider

Ciao
Greig
'57 750D
'60 10103 project
'60 10103
Others
 

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What about the rear mount? Is this the same in 101 and 750 cars? In other words, will the rear mount on the 101 gearbox fit into the cross member of Tony's 750 Spider?
 

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The rear mounts are transmission specific, not car specific, so Tony's car will use a split case rear mount - basically the same as a 101 chassis

The tunnel case rear mount is a completely different animal as is the rear mount for the later 1600cc Giulia 101's

Judicious shimming will keep all in line

Ciao
Greig
 

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I don't want to drag this thread out but if anyone can learn something from this here is a picture of two cross members. The one in the foreground is a standard cross member which could be used in conjunction with the spacers( both my '60 Normale and my '62 Veloce came with spacers). The one in the background would accommodate a later transmission without the spacers. The difference is obvious
 

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