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2600 TwinSpark Plugs - Engine

8K views 37 replies 19 participants last post by  tubut 
#1 ·
Hello,
here the Pic from the special 2600 Engine with TwinSpark Plugs.
Bernhard
 

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#3 · (Edited)
Bernhard,

That is a beauty! What is the 'back story' about this engine and is the head stock or modified for twin spark plugs? What distributor does it use? Also will the air filter housing be modified to allow more airflow for the Webers?

Finally, can we see a photo of the car it will go in? I hope you built an alloy body for it too.

Mark
 
#4 ·
Looks great, Bernhard -- I'm glad you got it finally made!!!
In addition to Mark's questions, what cams and piston were used and how much horsepower and torque does it create?
 
#8 ·
Hello,
owner of 2600 Sprint from France, I am new on the forum but not the first time I follow here the splendid restoration works that are presented here!
I am particularly interested by this work because it is what I have in mind since I have my 2600, among others modifications, in order to give this 6 in-line engine its real potential!
Bernhard, could you show us a picture of the combustion chamber in order to have a better view of the implementation of the second spark plug in the combustion chamber? Did you measure the thickness of the wall of combustion chamber in this area?
Do you know if some drawings of the cut (longitudinal or transversal) of the cylinder head exist?
As the others, could you tell us more about the other modifications of the engine?
What is the origin of the distributor you will use, and how will you fit the spark advance curves?
Will it go to the test bench before installation in the car?
I am sorry for the long list of question, but I am very excited by this transformation!!
So impatient to hear about your answers!
Have a good day,
Xavier
 
#9 ·
FYI, Bernhard let me know outside of AlfaBB that he is traveling abroad until Nov-22 and that he will try to answer questions after his return.
 
#18 ·
Twin plug 2600

May I ask how you came to estimate these 240 HP. It seems quite a lot to me and I wonder if you had the engine actually running on a test facility.
In my schooldays we used to have waterbrake and electric brake equipment. But at this moment of time I would not know of anyone with such equipment on the market in Holland.
 
#21 ·
Hi. Im new here. Is this engine original or had it been modified. Was the Zagato ever delivered with a twin spark engine?
There never was a 2600 twin spark engine in period (the one shown above is the first one I know of). The 2600 SZ engine was identical to the Sprint/Spider engine, except for the motor mounts (rubber blocks being 8-10 mm shorter required geometry adjustments) and using all-Bosch electrics with an alternator (instead of generator), internally referred to as AR*00612 engine, but stamped with a specific number range of AR*00601*10xxx.
 
#22 ·
Bernhard,
This is splendid. I echo the questions of others. As in the specifics of how you increased the fuel and Airflow. And did you increase the compression ratio- if so by how much? And how did you achieve this increase in compression?
Your work can be considered art because of the way you continually re-interpret these 2600 engines, who beg for improvement!
 
#26 ·
Bernard,

I have a spare 2600 engine being completely modified for a 2600 Sprint. Practically everything but the engine block, cylinder head, oil pan and cam covers will be changed out for improvements and the finished engine will be completely controlled by a Cosworth SQ6M ECU. Unfortunately, the Cosworth ECU can only control eight spark plugs so my question for you is if you designed the dual plug cylinder head with the idea to fire both plugs at the same time or one after the other for each cylinder. Normally, as I understand it, you want a dual plug cylinder head to fire the spark plugs one after the other.



However, I can't resist asking you what you would want to be paid for a twin plug cylinder head! It is such a neat product!
 
#32 ·
Another reason for the dual coil setup for hemispheric combustion chambers with very high compression ratios is the fact that the domed piston blocked flame travel from a single spark plug hence the need to have two plugs for proper flame travel after ignition. While a hemi combustion chamber, with a centered spark plug can product excellent combustion, modern high compression engines led to new combustion chamber configurations in order to have proper flame travel, particularly when you see the size of modern intake valves today and the amount of lift for them.
 
#34 ·
For some time I have wondered about a white 2600 Giulia Sprint that I remember seeing in the mid sixties, it had platinum plugs and the bit I can't find is that I remember it had a built in rear spoiler much like a DB4. No picture I have found to show this particular model, any help in identifying this model would be appreciated.
 
#35 ·
It sounds a bit like a 2600 SZ, see example here.
 
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