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[zp]

hi everyone

the other day i was having a look at some tech data concerning the 33.
so for series 3, fitted carbs are :
- two weber or two dellorto 40 for 1.3 engine
- two weber or two dellorto 36 for 1.5 engine
for previous cars, carbs are :
- weber 32, solex 32, or two weber 36, or two dellorto 36 for 1.3 engine
- weber 32, solex 32, or two weber 36, or two dellorto 36 for 1.5 engine
- two weber 40 for 1.7 engine

well i thought that the carb number (ie 32, 36, 40) reflected the size of the carb. so i don't understand why the carb size is the reverse of the engine size on the series 3 (or perhaps my data are wrong?)
besides, what are typically the bests carbs ever for a 33, i heard a lot that weber are better than dellorto, is this true? and what is the most desirable model?

thanks everyone for your answers

regards,
zp

[Admin]

Hi

Although the 33 series 3 1.5 is listed with carbs in the workshop manuals, I have never heard of one being sold. As such I suspect it was developed and then not put into production

My experience with the carbs is on earlier cars fitted with Dellortos and later cars with Webers, so this is biased a bit as they played with the jetting for emmisions reasons. However I prefer the Dellortos, with the later Webers giving a horrible jerky throttle

All the best

Keith

[zp]

Basically, as engine size increases, so too does the Weber / DellOrto size. For the 1.5, the 36 IDFs are specified. For the 1.7, it's 40IDF.

Webers tend to be easier to set up than DellOrtos - although those who stuff around with the latter will say the opposite! Essentially, they work in the same way, although DellOrtos tend to have a more complicated air mixing system. Best? Academic really. All things being equal, either will do, as long as they are properly set up and well tuned to match the engine. If you want to fiddle with either, change things one step at a time. For instance, don't change emulsion tubes and main jets at the same time.

[Admin]

Hi

By the way, forgot about this. Knocked it up ages ago. Page listing some of the jettings for the 33's

http://www.alfa-pages.co.uk/carbjet.htm

All the best

Keith

[alfafan]

"Although the 33 series 3 1.5 is listed with carbs in the workshop manuals, I have never heard of one being sold. As such I suspect it was developed and then not put into production "

This is not correct.
It depends on the different Markets.
Here in Portugal, you see "lots" of series 3 33 1.5 with carbs.
But after the beginning of 1993 the only version was the 1.5 IE (Catalitic).
I have a 1.5 V - My wife´s car - It´s Series 3 1.5 with Hidraulic Tapets, 40 mm Webers, sun roufe and AC.

Regards

Carlos Oliveira

[Admin]

Yey, another bit of info to add.

I had never heard of a series 3 fitted with carbs before now. For the UK all the series 3 cars were fitted with injectio, with the 1.5 dropped from sale for 1993 (the cat cars we got were the 1.7 8V and the 1.7 16V). I know Ireland (another rhd market) got 1.3 carbed series 3 cars

The question is where got the 1.7 with carbs, or the 1.2 (not sure if it is a typo in the manual fiche)

All the best

Keith

[neo]

Hi.

I also have a 33 (3rd series) 1.3 91' with factory fitted 2 IDF 40 carbs. The engine also has hydraulic tappets.

[Admin]

Hi

Think most of the cars went to hydraulic tappets around 1987. Not sure exactly when though

I have a lhd 1.3 from Belgium which is an early series 3 with carbs factory fitted. I also have the remains of a 1992 rhd 1.3 which again has factory fitted carbs

All the best

Keith

[Guest]

[alexj]

Just to clarify the above post, the earlier 1350 and 1500 twin carb engines all used 2xWeber IDF/Dellorto DRLA 36mm carbs. My understanding is that all the 1500 engines had 30mm main venturi and 1350 engines had 28mm main venturi.

For determining the character of the engine, it's the main venturi, not the carb barrel/throttle size that matters most.
Lex