Alp Sungurtekin 666 Vincent Speedweek SCTA BNI August 8-14, 2020

litnman

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With fuel injected nitro the barrel valve controls the pressurized fuel in conjunction with the opening of the carb slides. Like David said, the carbs are used for air control only while the
fuel is injected through nozzles between the carbs and the heads. This dwg is a typical layout.
Injected.png
 

greg brillus

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If that's a Joe Hunt mag I hope Alp has checked the timing on both cylinders as the ones I have both used or helped others with were out quite a lot. My guess is the cams they use have lobes for a 45 degree twin, as per Harley........I had to modify the front cylinder lobe to change the timing to the 50 degrees.......... actually 205 degrees apart.
 
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davidd

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If that's a Joe Hunt mag I hope Alp has checked the timing on both cylinders as the ones I have both used or helped others with were out quite a lot. My guess is the cams they use have lobes for a 45 degree twin, as per Harley........I had to modify the front cylinder lube to change the timing to the 50 degrees.......... actually 205 degrees apart.

It is a Morris mag. Dave at Morris showed me several 50-degree rings he had made, so I don't think that will be a problem. However, there has been some delay by the postal service on a different repair or mod and Alp may have to run a standard mag. The start-up and running are all about testing.

David
 

Gene Nehring

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Looks like in some of the photos he was using an alloy idler is that suitable for this type of racing? Hope he does not blow the crank through the bottom of the cases like dave Matson did with the burns rapide engine.
 

greg brillus

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The concerns I would have on a nitro engine is lack of clamping force with just four studs on each cylinder........a major worry with Nitro fuels is hydraulic locking from the cylinder going dead from an ignition failure.
 

davidd

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Gene,

I think it is just an older style of steel idler that had a different hole pattern. Pat made an effort to give Alp useable parts.

_MG_6283.jpg


Alp has done quite a bit of work with nitro and I think he is fairly conservative. His Triumphs use stock cast pistons and they have been timed running as fast as 189 mph. But, that is what testing is all about! He is running on petrol for testing.

David
 

Monkeypants

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Some beautiful work there!
Alp mentions using 2 ball bearings on the drive side. I wonder why he did not go with 1 roller and 1 ball as per stock?
The two ball bearings would give more lateral holding strength if both are with fixed in place outer races, however you lose on loading. The bearing load must be quite high with Nitro?
Also, I see the crank appears to be a fairly standard type Maughans full round with recessed nuts.
I wonder if the mainshafts are standard size?

Glen
 
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