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Hi to all

does somebody know the differences between the two engines or engine blocks with following enginenumber: 1306 and 1308?

As much as i know:

1306 was installed in 1900 Super
1308 was installed in 1900 Super Sprint

but i don't see any differences in the engine block? :confused:

Saluti from Switzerland!
Andy
 

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Initially, the Alfa Romeo 1900 engine had a bore and stroke of 82.55 × 88 mm giving 1884-cc displacement, hence the model designation. For 1953-58, dimensions grew to 84.5 × 88 mm for a total 1975 cc. The cars with the larger displacement motors are the Supers.
 

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Photo of basic difference betwen 1306 and 1308

1308 was basically double chain and an idler to tighten double chain in reworked head. 1308 engine had 1975 cc, and 1306 (someone said had only 1844, but not sure myself the actual).

Basically 1308 block also was used for 432 of the first two liter engines, and they had first, third and fifth bearing broader than other two. After 432 the engines have only first and third wider or broader. Most of the 432 on two liter are fitted to specific chassis, but NO two liter matches engine number and chassis number. If someone claims to have matching numbers, someone has changed nubmers. After 1960 only the chassis number is stamped on the firewall plate and they are for all intents and purposes interchangeable. But on pre 1960 they are random, (e.g., my spider AR10204*00126 has engine number AR00204*0074, but engine number AR00204*00063 is in a car with a chassis number almost 100 later than mine), Go figgur!! as they say.

Not sure you can read Italian, but you should be alble to see the difference if I could only get the photo back to right size in jpeg and add as an attchment. But I don't seem to be able. Dontact me direclty. I'll try drireclty. Have too tight a firewall and it won't let me send out on my own email. Will have to call somebody. [email protected] in Seattle.
 

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Lets look at pictures for difference

Well, I am trying again. Hope I can get it to work this time. Engine on left is 1306. Block is identical to one on right, but uses gears to drive timing and has no second chain. There is, of course, a head giving only 1844 cc displacement. The Engine on the right is the 1308, using a double chain system to time the cams and a second chain tensioner idler. It also has a different head to give a 1975 cc displacement. Both have the old style valve adjustment, not the cam follower bucket, button and common system since 1900 version. As indicated, the two liter engine was a logical progression on the 1308 and used the blocks for the first 432 engines. Sadly it tried to keep the 10 mm stems valves, but with the upgrade to cam follower, etc. But to get buttons to adjust them now is almost impossible. Best to make entirely new 9 mm stemmed valves of stainless steel, use new valve guides, and new valve seats. Even using 45% modern procedure and being careful to have slightly flattened seat on exhaust will make head last far longer than the initual expected 25,000 miles we old two liter owners experienced before the first head rebuild. I suspect 1900 owners have also experienced same problem combined with the wearing on the "adjustable lashup" for valve adjustments. I have one, but lack driving time on it. In time, perhaps . . .

Sorry if you cannot read Italian. I can make out what it says, but I would never dare translate. Hope this gives you a good idea of what is different between the two engines. The 1308 has more displacement and more horsepower. It is combined with different gearing also to give higher speeds in the vehicles.
 

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Discussion Starter #6
Thanks for the answers!

Unfortunately i have 'only' a 1306 engine for my 1900 CSS (56). Form outside the two engines looks for my very similar.

So i have to look for a original 1308 engine for my 1900 CSS.


Andy
P6190006.JPG

P6250026.jpg

P6250024.jpg
 

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I have one

Look at the other thread concerning differentials. I have a series two touring Super Sprint Coupe with 1308 engine. Your series three touring coupe looks beautiful. It needs a 1308 engine, truly. However, I would do lots of horse trading and selling if someone got me set up with a good body shell and interior of series II so I could unload mine without having to do it stock and make one that I would enjoy with various modifications from my experience throughout the whole 1900/2000/2600 lines.

So look at the other thread. Most of the engines, however, are also noted as being with specific chassis numbers on documents. I wonder how it would be to merely have a 1308 engine, but it not be the exact engine.

Regards, Jay
 

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I have never actaully worked on a 1900 and only have various books on the model, plus register documents and Fusi. I think the 1306 or 1308 actually has to do with the motor having a single or double timing chain configuration, and nothing to do with displacement.

If you look at the attached production chart, there are both 1306 and 1308 series motors near the beginning of production of the 1900 series (1950), and the 1975cc motor did not come out until 1953. The 1884cc motor is simply called 1900, and the 1975cc motor is called Super. TI relates only to the berlinas (with the exception of a handful of coupe built on the longer chassis), and means the car had two, 2 bbl downdraft carbs. As to the conv'ts, I believe all had one 2 bbl downdraft. Some coupes had one 2bbl downdaft, and some had two 2bbl downdrafts. The sidedrafts on some cars are a racing modification ususally done later, but some are actually period. I belive some of the very early berlinas had only one 1bbl downdaft.

All very confusing....and the chassis numbering system is even more confusing!

As to the Touring bodied cars, I would call the car above a Series 4 and not a Series 3. Series one was the five window car in which the doors went through the running board down to the bottom of the sides of the car. Series 2 was almost identical, but the doors stopped at the running boards. Series 3 has the larger 1975cc motor, a different front end, and narrower rear window pillars. Series 4 is the car as above, that looks kind of like a big giulietta.


http://home.comcast.net/~m.vallee/serialnums.html

As an example, Fusi says the 1st series of 1900 coupes had 1308 serial number motors. They were 1884cc and not 1975cc!

1900 Sprint 1st series S/N 1484
Chassis 1900C.00051 to 1900C.00058
Motors 1308.00001 to 1308.00008
 

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1306 versus 1308

Hi All,

Between the 2 iron-cast of the later "super" >1956 1306 and 1308 are no differences, the only differenc is that :

the 1308 :mounted in (1900css )

has an alu sump and a diagonal mounted oilfilter base plate

the 1306 : mounted in berlina super has a steel oilsump and vertical oilfilter and also I (think ) a heavier flywheel


REGARDS FRANCO
 

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1306 vs 1308 engines:
1306 is both 1884 and 1975 (Super) and is used in 1900 (1884 Berlina) and Super (1975 Berlinas).
1308 is both 1884 and 1975 and used in TI (1884 Berlina), TISuper (1975 Berlina), LWB Coupes and all SWB cars (mainly Coupes), 1884 and 1975.
Differences are many, both between 1306 and 1308 and 1884 and 1975. Blocks are basically identical between 1306 and 1308, all carrying 1306 part numbers, but from chassis 10001 (this will be the post-56 cars Franco is refering to) there is a 1308 part number block (no clue to what the difference is, but several other changes occured here, ie. flywheel and both engine end covers).
Change from one to two timing chains was at the 1884/1975 change.
1884/1975 increase is due a longer stroke crankshaft.
Many internal engine parts specifically used for the 1308 engines carry a 1306 number, so this is a cunfusing matter.
Carbs: at least 5 different single carbs were used on the berlinas (1884 and 1975), the very early ones a single sidedraft Weber 36 DO, as used in double or triple on the 6C2500. As Stu says, two twin vertical carbs (Solex 40PII) was used on the 1308 engines.
Oil sumps were all the same steel one on all 1884 (1306 & 1308), on the 1975 there were two different steel ones (one for 1306 and one for 1308), and an aluminium one for the post-10001 1308.

Hope this helps a little (and that I haven't made too many errors).

Erik S
 

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I don't think I have ever seen a 1900 with a 36DO sidedraft as was used on the 6c2500s, but the books show it as an option. I believe some of the early 1900 1884cc berlinas used one, 1bbl downdraft, but I am not sure of the carb type number.
 

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I don't think I have ever seen a 1900 with a 36DO sidedraft as was used on the 6c2500s, but the books show it as an option. I believe some of the early 1900 1884cc berlinas used one, 1bbl downdraft, but I am not sure of the carb type number.
Me neither, but there is one very early berlina in NZ which has the 36DO5 carb and manifold still with it. My early berlina (no 396) is totally missing its original engine, but I have indications that it was delivered with a 36DO5. After the sidedraft they changed (probably at car no 400-500) to a Solex 33PBIC, and later a Solex 40PAI.

Erik
 
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