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Discussion Starter #1
I've just started the restoration of a 1965 Giulia Spider Veloce (former owner should have been mr. D'Amico in Vineland, NJ)

The pistons are still there but I don't know:

  • If they are the original ones
  • If they could be recovered
I've talked with several Alfa guys, some say that the 121 engine pistons are different from the normal 1600 unit, others say they aren't but nobody can tell me exactly why. Is anyone here aware of such differences?

Capture.jpg

Queston #2: is the actual distributor the correct one?

25206274507_19542b82ff_z.jpg

Question #3: how high is the stock head of a type 121 engine?


Thank you in advance.
 

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To answer quickly some of your questions. The pistons are forged and not cast with a 9.7 to 1 compression ratio. The distributor is correct. The stock head height should be about 112 centimeters. Check the head fro cracks around the exhaust valve seats. It can be repaired successfully.
I would like to know more about the car for the 101 Veloce register. Send me a PM please. Thank you.
 

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Discussion Starter #3
To answer quickly some of your questions. The pistons are forged and not cast with a 9.7 to 1 compression ratio. The distributor is correct. The stock head height should be about 112 centimeters. Check the head fro cracks around the exhaust valve seats. It can be repaired successfully.
I would like to know more about the car for the 101 Veloce register. Send me a PM please. Thank you.
Hello Christopher, that's me, Francesco. You know the car:wink2:
 

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Grazie Francesco.
Check the top and 2nd ring gaps. No more than .003 thousandth clearance. Extra thick compression rings can be found.
There may be other opinions.
I would be more concerned about the condition of the liners.
 

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Discussion Starter #5
Grazie Francesco.
Check the top and 2nd ring gaps. No more than .003 thousandth clearance. Extra thick compression rings can be found.
There may be other opinions.
I would be more concerned about the condition of the liners.


Hi Christopher,
Liners are not a problem simply because are not there...I must buy them. I’ll must do some math as head is lower than 112 mm and I’ve seen that’s there are no 9.7:1 pistons for sale. Spruell has 9.5...


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I probably will dig my self a big hole here with some of my comments. Since you do not have any liners, call APE and ask Larry to sell you a set of liners. I am sure he has a nice stash of 1600 liners. You will need to have them honed for the rings you are going to use. The difference between 9.5 and 9.7 I would imagine is not that big of a deal in the final results of the horsepower derived. How are your cams looking? they should say 10121 on the markings. Check to see if there is a S or D on the cam to tell you where it goes on the exhaust or intake. It has been so long I might forgot that they can go either side.
 

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Discussion Starter #8
I probably will dig my self a big hole here with some of my comments. Since you do not have any liners, call APE and ask Larry to sell you a set of liners. I am sure he has a nice stash of 1600 liners. You will need to have them honed for the rings you are going to use. The difference between 9.5 and 9.7 I would imagine is not that big of a deal in the final results of the horsepower derived. How are your cams looking? they should say 10121 on the markings. Check to see if there is a S or D on the cam to tell you where it goes on the exhaust or intake. It has been so long I might forgot that they can go either side.


Hi Christopher, I’ll check for the liners but, first of all, I’ll verify if the pistons can be recovered. These are the cams:


@carl750 thank you very much for the photos, very useful


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Especially if you use the Veloce pistons, be very careful of prior head cuts that have made the valves to close to the piston. Also no extended reach spark plugs! If the head is warped ......... have it straightened ......... not cut!
 

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Discussion Starter #10
Especially if you use the Veloce pistons, be very careful of prior head cuts that have made the valves to close to the piston. Also no extended reach spark plugs! If the head is warped ......... have it straightened ......... not cut!
Thanks Carl. Actually the head is lower than stock, however I'll order a custom head gasket from Sangalli tall enough to compensate the lack of material.
 

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Discussion Starter #11 (Edited)
Ok these are the pistons, they look original, don’t they?
Unfortunately a couple are scratched so I’ve been told that the best thing to do, for a job like this, is to replace them.
Not easy at all to find that dome shape.




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Yes, those would cause hot spots.
You can have custom pistons made and I am sure there are folks on here that could give you some recommendations. Thank you for posting the photos. How is much ring land gap there with the rings installed? You should not have more than.003 That is the outside limit. Any more than that, you get ring float and then the ring will break. That is what happened shortly after I go my Veloce.
 

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I think this piston may be a standard GTA piston as evidenced by the arrow on the crown, and supported by the attached image from the Competition Advisory Manual, specifically the note stating that the arrow must face front toward the engine. With that said these should be forged 9.7 pistons, and could be used as a more or less proper substitution for the scarce proper velocity piston.
 

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Would electrolysis remove that rust and make the piston usable?

Ray
 
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