CT spring GTG May 7th 2016

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I will say ahead of time that the piston is a one of experiment. I tried something different with trying to "cylinder match" the sides of the piston. This piston actually was in my 346 and I simply re-purposed it. A new piston will be going back in my 346. While it looks kind of cool, I don't see it really making any difference. I don't anticipate doing it again.

Mattyo, should I post stuff like this in this GTG thread, or rather your dedicated 350 thread?
 
My measurements were:

Squish - .014". It was machined based on my 346 where it wasn't that tight.
Exhaust -106°
Transfers - 120°/122° staggered with the mains opening first.
Intake - 81°

You may notice that the main transfers are about .100" wider than stock. I only cleaned up the width on the secondaries. When case matching the cylinder base, I didn't just taper it into the duct, but took it all the way up to match with the widened main transfer port. This was an experiment, something that I've not tried on this model. I will be testing this with my 346, comparing it to another cylinder where the secondaries are widened like I normally do.

The cylinder wall was raised about .100" along the transfer ducts.

Both the intake and exhaust are 70% in width along the chord as compared to the bore. The intake is squared up on both the floor and roof, and the roof raised just a bit. The bulge in the one side of the intake was removed.

All of these details make a difference. It all adds up. Like I told Mattyo, it's more in the porting than the 357 intake system. I originally had the 346 intake and carb on it when I made the video. I considered leaving it on there just to make the point that it's mostly in the porting. I wad talked into switching it out when I pulled it back apart to add the impulse passage.
 
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