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Discussion Starter #1
My engine was smoking too much because valve guides were worn.
I started with the head and finished rebuilding the hole engine.
Kept pistons and cylinders that were in good shape from the previous rebuilt in 1985 but had to change the crankshaft.
I also lightened flywheel, about 900 grams less, machined edges were smoothed.
Everything was balanced.
Camshafts were already modified (but I have no specification).
Now the engine runs great (reached 6200 rpm) and no more oil clouds following me !
 

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Wonder why you lightened the flywheel? I understand this on high HP engines, but here it seems you just created a situation where when you shift the inertia is less so rpms will drop more. Please explain my error?
 

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A lot depends on the particular engine. The 1300 105 Jr engine is not the same as the 101 or earlier 750 1300's. In this case, the engine will be able to accelerate more quickly, overcoming flywheel inertia as 22# flywheel is too heavy for any Alfa engine at higher rpm. The wear on synchronizers is also reduced with imperfectly matched shifts. I lighten performance ALUMINUM wheels for 1600's to as little as 7#. In racing, steel 1600 flywheels to about 11#. His 105 1300 is very similar to my 1600's. 7# is difficult for some only on launch, with the car stopped. I have no problems down to 7# on the street, but have found that anything less can hammer the transmission with the engine power pulses.
My opinion only, from my experiences.
 

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Discussion Starter #7
My flywheel was lightened about 10-15% of its weight on the outer diameter (where a weight reduction really counts), as Gordon explanes, for serious performance and racing weight reductions are more radical (50 - 60% of reduction).

The engine had hotter camshafts before this rebuilt, regarding output what changed was:
- lightened flywheel
- balanced mainshaft & flywheel
- new carburettor setup (30 mm Venturis instead of 28 mm, different jetting)

It is difficult to say how much improvement comes from lightning and how much from balancing and carburettor setup. It feels like the engine accelerates quicker, I don’t miss any inertia and idle is at 900 rpm.
I’m really happy about the result and can only recommend this modification.
 

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Richard Jemison
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Lighter flywheels

Wonder why you lightened the flywheel? I understand this on high HP engines, but here it seems you just created a situation where when you shift the inertia is less so rpms will drop more. Please explain my error?

The whole idea is to get the RPMs to drop faster to ease syncro engagement.
 

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Discussion Starter #9 (Edited)
I really don’t notice any excess in rpm drop while shifting.
As I wrote before, it feels like the engine accelerates quicker, but I can’t say how quicker.

The work was done by people that know these engines very well, one of the machinists is nearly 80 years old, he told me about the long time he spent working at Autodelta and testing the cars they built. He is quite angry now because his sport driving license hasn't been renewed and he can't drive on the track anymore. It was really a great experience to speak with this man. Those times were really different from today.

I must admit that at the beginning I was a little skeptic about lightening. This people told me that for a light tuned 1300 street engine the best is to reduce weight by about 1 kg (standard weight should be around 9,5 kg).
So this lightening is quite mild compared to what I suppose Richard means with a light flywheel.
I think excessive rpm drop while shifting will occur with a 3 or 4 kg flywheel.
I can’t be scientific in my statements, only sensations, theese cause a lot of smile in my face while driving and this is what all of us are looking for.
 

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If Alfa engineers only knew what we know now !!
;^)
I'm sure they did, but selling to the general public where 90% of buyers are posers who only want Sporty cruisers, not real canyon carving temperamental beast, means they compromise more than 10% of us like.
 

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You left out that they often cannot operate a clutch or match engine speeds at gear change either. Further Alfa dealers did a lot of business rebuilding transmissions, and replacing clutches. They made money off that. Today we all know about the dreaded second gear crunch and the cost and irritation of replacing synchros. Why hasten wear on a great transmission with a heavy flywheel?
 

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So an Alfa is a poor design for sporty driving AND the dealers benefitted by their poor design and unskilled drivers by the frequent trans and clutch rebuilds.

How did they ever stay in buisness ?
 

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Don't you remember? They DID go outta business in the USA.
 

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I think it says more about the Amertican market than Alfas ability to build great cars.

Acalvi can tell us about the European Alfa models and some of their 'poser' owners......
 

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Discussion Starter #16 (Edited)
I was born in Milan 1961, in the late sixties / beginning of the seventies my father used to drive a 1750 Berlina and later, after it was stolen, a 2000 Berlina, my mother (german) drove a BMW 1602 and after a BMW 2002 Touring, so, for those days, fairly good cars in my family.

The approach to these cars, we now define as sporty classics, not only Alfa Romeo, also Lancia, BMW etc. is very different today compared to the time those were on the market,.
Further, the differences between US and Europe regarding market, customer requirements, taste, way to drive, roads, petrol cost etc. were a lot bigger in the sixties - seventies than today in the globalized market.

So the discussion about quality of design and driving skills might become complex because there are so many aspects to consider (this might become a new interesting tread).

Cars like Giulia or Lancia Fulvia were cars for the middle class.
GT 1300 Junior or Lancia Fulvia Coupè were dream cars for young people, normally lucky to drive their mothers Fiat 500.
2000 Berlina or a Lancia Flavia were a cars for a lawyer or a boss of a small/middle company.
These cars were all daily drivers for italian roads, mostly driven by men, in some rare cases by women.

Automatic transmission was completely unknown in Italy at that time (in some way, even today), people knew how to operate a clutch because everybody learned to drive on cars with non synchronized gearboxes, to shift down they had to know how to make a “doppietta” (I don't know the english for that). I wonder how many of you are able to shift down a non synchronized gearbox, at those times also grandma knew how to do it.

Cars were designed to last >10 years and engines about 100.000 km; today a car is mature for the scrap yard after 4 - 5 years with not many more km. So, considering the different times, one could say that design isn’t much better today.

At that time a clutch had to be replaced after 40 - 70.000 km, depending from the driving style.
Shops had a lot of normal maintenance to do like oil change every 5000 km etc. and it was normal to rebuild engines more than one time during the entire life of a car. The work of a mechanic was very different from today.

Cars with poor design didn’t stay in business at that time like it happens today.

And regarding quality, I can remember my father, after the 2000 Berlina, bought a Volvo, I think a 244, a nightmare! No power, high fuel consumption, no brakes, bad suspension, parts falling off etc. Volvo is still in US, Alfa had to leave. So things used to be / are very different seen from the two sides of the pond.

Im looking forward to read your comments!
 

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Excellent commentary, with a real world point of view.
 

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Cars were designed to last >10 years and engines about 100.000 km; today a car is mature for the scrap yard after 4 - 5 years with not many more km. So, considering the different times, one could say that design isn’t much better today.
That is not the experiense I have, In my oppinion modern cars are built to last much longer. They are carefully designed and protected from factory to resist rust much better than 20-40 years ago. At that time it was not unusually that a brand new car could show signs of rust. Nobody would accept that now.
Modern engines are not designed to be rebuilt, but it is still possible if somebody wanted to undertake such a task, the price of man hours are just to high to make it profitable.
In return modern engines are designed to last much longer. Most european engines sees at least 350.000 km and if properly maintained most of them lasts way more.
 

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The engineering analysis of the initial design is better today, as computers can accurately predict the street life of a specific spot weld related to body flex and so on. However even the best engineered cars made today, are designed with a specific anticipated service life, otherwise, any auto builder could put themselves out of business by building a car that could be economically repaired, essentially forever!
 

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Discussion Starter #20
I totally agree with what Lani and Gordon say.
My statement wanted to be a little provocative, a reaction to the idea about poor design of Alfa Romeo.
The design just was up to date, based on the technologies and Knowledge of those days.
Alfa Romeo were designed at a high level, with something magic other makers didn't have, the demonstration is our love and passion for these cars.
 
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