Lightning Performance,
From some of your previous answers about technical things on saws, I figure this question might be easily explained by you on some older saws I have.
I know it is not specifically on track here in the 400C thread, but it is top end related. I thought maybe you might have an answer for me.
A few years ago, I bought 2 well used and a little abused, Stihl 1111 series saws. An 075 and an 051. I pulled the top ends off both to find scoring and aluminum transfer so I got OEM top ends for both. The markings are all correct, and the boxes etc, But upon eyeballing things, I found quite different looking cylinders than what I presume were the original factory ones. Basically the differences amount to fatter casting of the fins which leave less air space vs thin fins and more air space on the old ones.
Ever seen this and know why they look different? I can think of one possible reason if I compare what I know about 044 cylinders for example. Mahle vs KS etc. I didn't think to look to see if a different "vendor" made the new ones I got.
Here are 2 examples from ebay that illustrate what I have.
1st pic is thin fin, 2nd is fatter fin.
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