If I do a big bore upgrade from a 96" to 103". Is there any Benefit in the way of noticable power gain when going to the biggest over sized pistons .010" over or would I be better off to stay with standard bore for durability and cooling?
I do like the idea of keeping the cylinder walls as thick as possible. I know you can take the stock bores to 107" but again I worry about reliability and longevity of my motor...not to mention that I would have to reeplace the entire cylinder if I had mine bored to 107" and needed to go oversized in future as opposed to a small oversize boring..

 

Short answer: No

 

Longer answer.

Bore to 3.938"; been done for years now, very common once everybody got over the "sky is falling" fear of thinning the cylinder spigot when folks first started the practice about 8 years back. So what if you have can't re-bore the cylinders after 75K miles. you can buy a set of take off OEM cylinders for not much more than the cost of the re-bore.

 

No worries whatsoever with boring to the 3.937" dimension.
We have over 825 in service since 2006(98" and 107" combined).
Our #HMM0107's and #HMM0980's(your cylinders) with a complete Cometic top end gasket set, rings are gapped and installed on the pistons, cylinders precision bored, and Sunnen torque-honed, measured with Mitutoyo bore guages................only $700.00.
Scott

 

Been done longer than I remembered.

 

I'm running a 105 incher. 103, 30 over forged 10:5:1 pistons. Pulls like a locomotive!

 

So what head gasket size are you running? 3.905" ? I'm curious what is the rest of your build?
Cheers

 

I have gone with a S&S 106 BB upgrade 10.1 kit, S&S crank,S&S TC3 oil pump and cam plate. I have 103 ACR heads. I am either getting a refresh with a radius valve Job or a stage two that will include the radius valve job, 1.9 intake valve.with heavier springs. However, leaning toward the first option.
I have an SE 255 cam will this cam work?
I am looking for cam that will be a low-mid cam I want cam that doesn't have a real lope atlopee or super high cc and compression. A nice street cam
suggestions wanted.

 

At 10:1 the 255 won't be a good fit. Maybe the S&S585.

 

The 585 is more of a mid range range cam isn't it? What would be the point at which a cam like the S&S 585 would kick in?