What's the purpose of this?

[Z.hb71]

The little devider in middle of the exhuast port, curious.

 

[Teejay112]

The little devider in middle of the exhuast port, curious.View attachment 48262

I think it supports the ring because those engines have a large exhaust port stops the ring snagging just a guess

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[Z.hb71]

I think it supports the ring because those engines have a large exhaust port stops the ring snagging just a guess

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That is a very logical guess.

 

[Basher5iveT420]

Maybe for some type of back pressure ??
I recently looked into the engine in my 5iveT and didn’t notice this

 

[Phill2]

Maybe for some type of back pressure ??
I recently looked into the engine in my 5iveT and didn’t notice this

My Zen doesn't have it and neither did my CY?

 

[Z.hb71]

My Zen doesn't have it and neither did my CY?

Maybe for some type of back pressure ??
I recently looked into the engine in my 5iveT and didn’t notice this

I think it's what @Teejay112 said, the zenoahs don't have huge exhuast ports

 

[Top Dead Center]

@Teejay112 is spot on. Page 109 of the actual document has the answer you seek. http://www.amrca.com/tech/tuners.pdf Somewhere around the mid 20s he talks about piston crown expansion. I think it serves both purposes.

 

[Seandonato73]

Its the ring bridge like mentioned above.

 

[TODD]

True like what was mentioned. Keeps the piston from rocking over and guillotining the ring. With wide exhaust ports there is no support for diameter of the piston to bore. So a manufacturer will have to add a bridge to it. Some motorcycles and water craft have these also.