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Discussion Starter · #1 ·
Hi all I would like opinions based on experience. I am rebuilding the engine in a 1600 sprint GT I have the original block but it was fitted with a later cylinder head when it arrived. I can source a correct cylinder head for the engine but it is without cams and cam caps. My question is can I source some cams and cam caps and make it work or will it involve line boring and lots more cost?
Tim
 

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In my experience swapping cams - no problem, it's no different than any other engine in that regard. New tappets and proper break in. Cam caps are a different story. They were assembled and then align bored at the factory on a torque plate (that is the reason for the 1/2 moon relief at the back of the head). You can try to gather a set of caps and torque the head to a block with an old head gasket. next install the cams and attempt to turn them (ALWAYS PRE LUBE). Mix and move the caps around until you have a proper fit. Double check clearances.

Bear in mind I am not the smartest or most experienced member here so a grain of salt is provided with all advice.
 

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Richard Jemison
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Cam caps

Best to find a head with caps. They are line honed and caps from other heads will have to be machined to fit. It requires a very small honing bar and you will be hard pressed to find such in machine shops.

Another issue is the clearance required between cam and the head/cap bore. It is only .0008 to .0015. Worn cam caps are the primary reason higher milage Alfas have low oil pressure at idle.
All of the wear is primarily on the caps due to spring pressure pushing the cam upward (and opening the clearance gap under the cam where oiling can easily escape lowering oil pressure). The more the caps wear, the faster they wear due to lack of oil pressure to lube the cap side of the cam journal.

The other wear point is the cam bearing in the #1 (exhaust) bearing area on the head area from the force of the cam chain pulling the cam down as it runs.

I made a tool to cut caps and straighten the cam bearing bores, to restore clearances. It is a tedious and time eating process, but makes the oiling efficiency as designed.
 

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If you are looking to build a concourse car, you need to understand some 101 1600 history. What~ year was your car built? The first 1600 101 cars had a head derived from the 1300 101 head. Intake port runner size was increased along with valve size, and CC from 74mm to 78.
This head worked pretty good on Normales, but on Veloces, combined with the Veloce cams, was noted for a lumpy idle and poor low end torque. About late '63- early '64, another problem appeared, more serious. These heads began to develop combustion chamber cracks. They began at the spark plug hole bottom thread, and extended to the exhaust valve seat. Alfa was already using soduim cooled exhaust valves by this time on both Normale and Veloce versions. The cracks initially would appear on the C.C. surface, and over time deepen until they penetrated to the coolant passages. At first, owners were forced to buy new heads (101), but some owners had those quickly fail as well. PreRecall! Owners WERE ANGRY!
Alfa was well into the 105, design and engineering, by '64, and began to offer FREE replacement heads with a 105 casting number to owners with failed 101 heads. You still paid for labor. This head was 105 SMALL PORT, and was a redesigned casting. Same size valves. With the Veloce cams, it idled smoothly, and had better low end torque! What's not to like? Well, they did not offer a FREE 105 small port matching manifold. If you wanted ports to match, you needed that, or to do some porting work. The engines ran fine with mismatched manifolds and heads.
Today, most 1600 101's that are and were driven, will have the 105 casting number head. This has NO front cover hold down bolt holes, and appears just like the 101 casting number head, BUT it was a major engine build improvement. 101 casting number 1600 heads were possibly used to the very end of pre Duetto production. My car, a late '65 Veloce came with a 101 casting number head. This car, an Ausca Spider, had complete GTA running gear installed as new in '65 at Ausca.
Both Ausca, and Knauz Continental Auto's in Lake Forest Illinois did considerable 101 casting number head replacements with the later 105 casting number head on 1600's.
So, if your 1600 has a 105 casting number head WITHOUT front hold down bolt hole ears, it IS concource correct as a factory replacement head, authorized by Alfa Romeo.
From my experience.
 

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Discussion Starter · #5 ·
Thanks to all who commented, I will ask the owner if he knows where the other parts are but I fear they were separated long ago in which case it does sounds like I should search for another cylinder head. The car is a 1964 Giulia Sprint Gt.
Tim
 
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